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Baywax
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JupiterSomeone brought up Jupiter in a conversation and it was because recent theories suggest that the core of Jupiter is a large diamond (carbon) pressurized to such a state by the many layers of different gases there. Is this at all possible?
There are also one or more theories that proport how Venus was separated out the a larger Jovian body. It is thought that this separated bit of Jupiter hit Mars before settling into its present orbit as Venus. Is this at all a possibility?
Thank you.
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Bystander
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Re: Jupiter | Baywax wrote: | Someone brought up Jupiter in a conversation and it was because recent theories suggest that the core of Jupiter is a large diamond (carbon) pressurized to such a state by the many layers of different gases there. Is this at all possible?
There are also one or more theories that proport how Venus was separated out the a larger Jovian body. It is thought that this separated bit of Jupiter hit Mars before settling into its present orbit as Venus. Is this at all a possibility?
Thank you. |
The educational benefits of roadkill dissection are greatest when the dissection is performed by the finder of the roadkill: for diamond, consult your freshman chem. text; the Velikovskian Venus road pizza is the most persistent grease spot to ever stain an interstate, but can be removed by applying bleach and a freshman physics text.
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Baywax
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Re: Jupiter | Bystander wrote: | | Baywax wrote: | Someone brought up Jupiter in a conversation and it was because recent theories suggest that the core of Jupiter is a large diamond (carbon) pressurized to such a state by the many layers of different gases there. Is this at all possible?
There are also one or more theories that proport how Venus was separated out the a larger Jovian body. It is thought that this separated bit of Jupiter hit Mars before settling into its present orbit as Venus. Is this at all a possibility?
Thank you. |
The educational benefits of roadkill dissection are greatest when the dissection is performed by the finder of the roadkill: for diamond, consult your freshman chem. text; the Velikovskian Venus road pizza is the most persistent grease spot to ever stain an interstate, but can be removed by applying bleach and a freshman physics text. |
Ok then. Next!
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Baywax
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Actually we are just gaining the technology to understand what is going on at the centre of the giant planets in this solar system and outside of it.
| Quote: | "The center of Jupiter is at about 70 million atmospheres," which until now has been inaccessible, Jeanloz said. "We want to be able to understand the hundreds of planets that have now been found that are massive enough that their central pressures are many hundreds of millions of atmospheres, and maybe a billion atmospheres."
In a diamond anvil, a tiny sample - either liquid or solid - is compressed between the tips of two diamonds. In the combined technique, several powerful laser beams zap one of the diamonds, vaporizing it and sending a shock wave through the sample that compresses it even more. The shock wave compresses the sample for 1 to 2 nanoseconds, enough time to study the properties of the sample, which can range from hydrogen and helium, the stuff of stars and giant planets, to elements that comprise Earth. |
http://www.astrobio.net/news/modu...ews&file=article&sid=2326
The use of the diamond anvil may be what is being mis-understood and interpreted to mean that there is a diamond at the centre of Jupiter.
But, Arthur C. Clarke is the source of the idea that there may be an earth sized diamond at the core of Jupiter.
Here's the question about it and the answer at this site.
http://www.astronomycafe.net/qadir/q2270.html
[img]http://starryskies.com/articles/2004/02/diamond.jpg
[/img]
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Andre
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If iron is the most abundant element judging the meteorites etc, and it's perceivable that molten iron seeps into the core of protoplanets, then why would the core of Jupiter not being dominated by iron, fluid and solidified just like the Earth core??
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scpg02
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| Andre wrote: | | If iron is the most abundant element judging the meteorites etc, and it's perceivable that molten iron seeps into the core of protoplanets, then why would the core of Jupiter not being dominated by iron, fluid and solidified just like the Earth core?? |
Because it's farther out. heavier elements were closer to the sun in the accretion disk. Lighter gasses farther out. At least that's what I was taught.
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Baywax
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On to Venus.... is it Jupiter's little baby?
Instant criticism of this theory will not be taken seriously. Some of the sources that started the theory are admittedly questionable... for instance the old testament of the "bible".... some of the sources are as credible as any source such as ancient Iranian and Chinese astronomical records.
You can find out more about Velicovsky here
http://en.wikipedia.org/wiki/Immanuel_Velikovsky
There is a good synopisis of his explainations here
http://unmuseum.mus.pa.us/velikov.htm
| Quote: | Velikovsky attributed many of the disasters recorded in ancient times to this strange interaction the Earth had with Venus. Material that fell from Venus's comet tail into Earth's atmosphere caused the plagues visited upon Egypt as recorded in the Bible. "Plague is throughout the land. Blood is everywhere," cried the Egyptian Ipuwer. "Men shrink from tasting, human beings thirst after water..." According to Velikovsky's thinking, a fine rusty ferruginous dust from the comet's tail filtered down on the globe turning everything red.
As Earth went deeper into the comet's tail the dust turned to small stones and a hail of gravel pelted the Earth: "...there was hail, and fire mingled in with hail, very grievous, such as there was none like it in all the land of Egypt since it became a nation," the Bible reads.
Velikovsky also credits the manna that nourished the nation of Israel during their forty-year wandering through the desert in Exodus to carbohydrates that fell to Earth from comet Venus's tail.
The changes in rotation, according to Velikovsky, caused a prolonged darkness over the Earth. His research discovered that in Iran scholars recorded a night lasting three days followed by a day lasting three days. The Chinese recorded the same phenomena. The Bible speaks of a day when the sun stood still to allow Joshua to finish a battle. |
To disregard anyone's theories before making the same observations that steered the theory to its conclusions.... and not wieghing the evidence with an unprejudiced and open mind is wrong every case. To take Carl Sagan's criticisms verbatum and cease any research into the theory in question is wrong as well.
So, I am posting this theory along with Arthur C. Clarkes's for just this sort of open minded and (hopefully) excruciatingly detailed scrutiny.
Something that seems to lend validity to Velikovsky's theory is that Venus is an anomally. Its is a "new" planet. It is radiating heat more than it is absorbing it and its rotation is the reverse to other planets in the solar system. If there are findings to the contrary please feel free to post them here.
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AstrumAspicio
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Re: Jupiter | Baywax wrote: | Someone brought up Jupiter in a conversation and it was because recent theories suggest that the core of Jupiter is a large diamond (carbon) pressurized to such a state by the many layers of different gases there. Is this at all possible?
There are also one or more theories that proport how Venus was separated out the a larger Jovian body. It is thought that this separated bit of Jupiter hit Mars before settling into its present orbit as Venus. Is this at all a possibility?
Thank you. |
The best evidence is that Jupiter's core is comprised of metallic hydrogen. Also celstial mechanics does not allow venus to have been thrown out of Jupiter. Venus has been in its present orbit for billions of years.
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AstrumAspicio
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| Baywax wrote: | On to Venus.... is it Jupiter's little baby?
Instant criticism of this theory will not be taken seriously. Some of the sources that started the theory are admittedly questionable... for instance the old testament of the "bible".... some of the sources are as credible as any source such as ancient Iranian and Chinese astronomical records.
You can find out more about Velicovsky here
http://en.wikipedia.org/wiki/Immanuel_Velikovsky
There is a good synopisis of his explainations here
http://unmuseum.mus.pa.us/velikov.htm
| Quote: | Velikovsky attributed many of the disasters recorded in ancient times to this strange interaction the Earth had with Venus. Material that fell from Venus's comet tail into Earth's atmosphere caused the plagues visited upon Egypt as recorded in the Bible. "Plague is throughout the land. Blood is everywhere," cried the Egyptian Ipuwer. "Men shrink from tasting, human beings thirst after water..." According to Velikovsky's thinking, a fine rusty ferruginous dust from the comet's tail filtered down on the globe turning everything red.
As Earth went deeper into the comet's tail the dust turned to small stones and a hail of gravel pelted the Earth: "...there was hail, and fire mingled in with hail, very grievous, such as there was none like it in all the land of Egypt since it became a nation," the Bible reads.
Velikovsky also credits the manna that nourished the nation of Israel during their forty-year wandering through the desert in Exodus to carbohydrates that fell to Earth from comet Venus's tail.
The changes in rotation, according to Velikovsky, caused a prolonged darkness over the Earth. His research discovered that in Iran scholars recorded a night lasting three days followed by a day lasting three days. The Chinese recorded the same phenomena. The Bible speaks of a day when the sun stood still to allow Joshua to finish a battle. |
To disregard anyone's theories before making the same observations that steered the theory to its conclusions.... and not wieghing the evidence with an unprejudiced and open mind is wrong every case. To take Carl Sagan's criticisms verbatum and cease any research into the theory in question is wrong as well.
So, I am posting this theory along with Arthur C. Clarkes's for just this sort of open minded and (hopefully) excruciatingly detailed scrutiny.
Something that seems to lend validity to Velikovsky's theory is that Venus is an anomally. Its is a "new" planet. It is radiating heat more than it is absorbing it and its rotation is the reverse to other planets in the solar system. If there are findings to the contrary please feel free to post them here. |
I don't have time to go into it this evening, however, Velikovsky has been completely debunked.
Will post more tomorrow.
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Andre
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Baywax
I'm afraid I have to agree with AstrumAspicio, about the physical impossibility of Velikovsky's Jupiter - Venus construction. The impossibility for instance, of the planets having solid stable near circular orbits. If Venus had emerged from Jupiter, it potential energy was to be so big that it would have to be in a highly eccentric orbit around the sun, if it was orbitting at all. And if Venus would have had a close encouter with Earth (Wolds in collision) then Earths orbit would have been destabilized as well due to mutual gravity interaction.
Open mindness is a great thing, but you have to test your ideas against physics and reality. The proof is in the pudding.
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Andre
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| scpg02 wrote: | | Andre wrote: | | If iron is the most abundant element judging the meteorites etc, and it's perceivable that molten iron seeps into the core of protoplanets, then why would the core of Jupiter not being dominated by iron, fluid and solidified just like the Earth core?? |
Because it's farther out. heavier elements were closer to the sun in the accretion disk. Lighter gasses farther out. At least that's what I was taught. |
Thanks, Interesting, it would however not explain why Earth is heaviest of the terrestrial planets, Venus being clearly less dense. Also if Jupiter has so many solid moons with heavier elements, why not the core?
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Baywax
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| Andre wrote: | Baywax
I'm afraid I have to agree with AstrumAspicio, about the physical impossibility of Velikovsky's Jupiter - Venus construction. The impossibility for instance, of the planets having solid stable near circular orbits. If Venus had emerged from Jupiter, it potential energy was to be so big that it would have to be in a highly eccentric orbit around the sun, if it was orbitting at all. And if Venus would have had a close encouter with Earth (Wolds in collision) then Earths orbit would have been destabilized as well due to mutual gravity interaction.
Open mindness is a great thing, but you have to test your ideas against physics and reality. The proof is in the pudding. |
Ah... so the physics doesn't jive!
That would go a long way to explain a quick dismissal of the theory. I'd still like to see the actual arguments pitted against the claims. For instance, why are there identical accounts of a night lasting 72 hours and a day 72 hours from Iran and China? Also, what can explain the fact that Venus appears to be a much newer planet with various anomalies like radiating heat and a reversed rotation?
If Venus didn't hit Mars then what did take half of Mar's crust off and leave her as desolate as she is today?
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Andre
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| Baywax wrote: | For instance, why are there identical accounts of a night lasting 72 hours and a day 72 hours from Iran and China?
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I am afraid I'm not familiar with that. I am familar with:
http://seds.lpl.arizona.edu/nineplanets/nineplanets/earth.html
| Quote: | | The interaction of the Earth and the Moon slows the Earth's rotation by about 2 milliseconds per century. Current research indicates that about 900 million years ago there were 481 18-hour days in a year |
Although I haven't seen the study about that. Somebody?
| Quote: | | Also, what can explain the fact that Venus appears to be a much newer planet with various anomalies like radiating heat and a reversed rotation? |
Happy to explain that here.
| Quote: | | If Venus didn't hit Mars then what did take half of Mar's crust off and leave her as desolate as she is today? |
I'm sure that one day somebody will think of an alternative. It's not so that if we can't think of any other solution, that our ideas must necesarily be true. Our perceptions about those things are still very limited
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Baywax
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| Andre wrote: | | Baywax wrote: | For instance, why are there identical accounts of a night lasting 72 hours and a day 72 hours from Iran and China?
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I am afraid I'm not familiar with that. |
I'm afraid it all starts with a famous incident in the much edited bible about Joshua asking the sun to "be silent" and "stop working" so he and his gang of hebrews can take revenge on an enemy.
| Quote: | Joshua’s Long Day around the World?
Having concluded that Joshua’s long day is a miracle, we may ask whether or not it was restricted just to the area of Canaan or whether it was global in scope. Certainly a “missing day” would generate considerable consternation among the peoples of the world, provided it was a global event. Are there other accounts of a long day or even a long night? Indeed, we can find stories of a long night as well as a long day. We can even find tales where the sun hung near the horizon for a long time. All the accounts taken together allow us to ascertain the time of day when Joshua told the sun to stand still.
Some of the world’s recitations of Joshua’s long day are vague and unspecific while others are quite clear. Among the former are those which relate only that the people had knowledge of the concept that the sun, moon, and stars can reverse their motions. An example of one of these is the account referred to by Augustine in The City of God where he quotes the Æneid about a witch who:
...can reverse the wheeling of the planets, halt rivers in their flowing.22 |
http://www.geocentricity.com/astronomy_of_bible/jld/index.html
and
| Quote: | | One of Totten’s sources is a report by the Greek historian Herodotus who wrote that when he visited Egypt, the priests there showed him an ancient manuscript which told the story of a day which lasted about twice as long as a nor mal day. Now the Egyptians had water clocks at that time so that they could accurately measure the duration of the day, not being dependent on the motion of the sun, moon, and stars, as would other peoples around the world. Totten’s second account is from the Chinese which we shall present later. |
same source
and the Eqyptian account
| Quote: | For the Egyptian account, we find that the French classical scholar, Fernand Crombette, translated some Egyptian hieroglyphics which tell of Joshua’s long day.25 The text starts out with an edict from the king to exempt from taxation those who had been victims of a flood some two weeks earlier. Evidently the flood had been caused by an unusually high tide. The cause, according to the Egyptian hieroglyphics, was:
The sun, thrown into confusion, had remained low on the horizon, and by not rising had spread terror amongst the great doctors. Two days had been rolled into one. The morning was lengthened to one-and-a-half times the normal period of effective daylight. |
and the Chinese account
| Quote: | The second secular source about Joshua’s long day, which was mentioned by Totten, is based on what seems to be a recently lost ancient Chinese manuscript. In 1810 Gill presents the account:
In the Chinese history27 it is reported, that in the time of their seventh emperor, Yao, the sun did not set for ten days, and that men were afraid the world would be burnt, and there were great fires at that time; and though the time of the sun’s standing still were enlarged beyond the bounds of truth, yet it seems to refer to this fact, and was manifestly about the same time; for this miracle was wrought in the year of the world 2554, which fell in the 75th, or, as some say, the 67th year of that emperor’s reign, who reigned 90 years.28
Now the year of the world 2554 is identical to Bouw’s independently derived biblical chronology for the date of Joshua’s long day.29 Incidentally, note that a 90-year reign (not Yao’s age) is thoroughly consistent with the 110 to 120 year ages achieved by Moses, Aaron, and Joshua who would have been contemporaries of Yao. The length of time mentioned by the Chinese, ten days, may be too long simply because the Chinese did not have clocks which ran independently of the sun’s motion so that the estimate would be purely subjective. Probably, the duration was exaggerated both by the trauma of the event and in the transmission of the story through time. |
In North America
| Quote: | Tales relating to Joshua’s long day abound in North America. Almost all of the tales in North America tell of a long night. The only exceptions are those related in the chapter on Hezekiah’s sign. Olcott31 has collected five of particular interest.
The Ojibways tell of a long night without any light.32
The Wyandot Indians told missionary Paul Le Jeune of a long night.33
The Dogrib Indians of the North-West tell of a day when the sun was caught at noon and it instantly became dark.34
The Omahas say that once the sun was caught in a trap by a rabbit who checked his traps at the break of dawn, presumably before sunrise.35 (This may be Hezekiah’s sign, instead.) Finally,
the Bungee Indians from the Lake Winnipeg area of Canada also tell of a long night.36
The preponderance of long night tales in the Americas would rule out the theory that Joshua’s long day was a miracle which was local to Canaan. It also rules out the speculation that the story migrated around the world, for then it would everywhere be a long day (or a long night), but not a mixture of long days and long nights. |
And in Central and South America
| Quote: | Turning to the south, we find that Central and South America similarly experienced a long night. In the Annals of Chauhtitlan, the Mexican Indians tell of a long night. The Aztecs wrote of an extended period of time when the sun did not rise. According to their legend, there had been no sun for many years.
... So a conclave of the gods was called in Teotihuacan, and there it was decided that one of them should offer himself as a sacrifice that once again the world might have a sun ... The sacrificed gods had disappeared in the brazier’s flames, but as there was no sign of the sun, the remaining wonder when it would first appear. At long last, the sun burst forth ... But the sun, despite his brilliant light, did not move; he hung on the edge of the sky, apparently unwilling to begin his appointed task.37
Likewise, in their national book the Popol Vuh, (which translates into “Book of the Princes,”) the Quiché Mayans of Guatemala wrote about the people’s reaction to a long night with these words:
They did not sleep; they remained standing and great was the anxiety of their hearts and their stomachs for the coming of the dawn and the day ... “Oh, ... if we only could see the rising of the sun! What shall we do now?” ... They talked, but they could not calm their hearts which were anxious for the coming of the dawn.38 |
And a computer's account......
| Quote: | | A second computer account of a missing day appeared in the Swedish Goteborgs Tidningen on March 15, 1981. According to that story, Stig Flodmark of the University of Stockholm had discovered that the earth’s axis had flipped on May 3, 1375 B.C. and associated that with Joshua’s long day. This proposal is the same as that of Rand who was mentioned earlier in this chapter. According to Flodmark, an Ugaritic astronomer described the event and gave the date. Flodmark refers to a book entitled Tidal Friction and the Earth’s Rotation.48 The comment by the author of the quoted paper, F. R. Stephenson, in summarizing the Ugaritic observation, is “Sun put to shame; went down in daytime.” This hardly describes a tippie top phenomenon, especially with Gibeon at the rotational north pole for the day, for the sun would have been circumpolar for the Ugaritic astronomer; it would not have gone “down in daytime.” |
All quotes from http://www.geocentricity.com/astronomy_of_bible/jld/index.html
I forgot to interject a story from the Pacific Northwest about How The Raven Stole The Light....... it relays a period in every westcoast nation's history when there was no light for a decidedly long period.
Then, after this period things began to return to normal with the sun rising yet, the night sky presented quite a spectical of fireworkes over some period.... like what might happen if Mars was in a collision with another body.....!!!
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Andre
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Wow, that's quite something here.
I googled a bit that's a whole other world it seem
So we have anectdotal evidence that something weird happened to good old Earth. It skipped a day!? But how? Doing something with the rotational axis? Let's see if we can sciencify that (I love inventing new words).
So we have observations of long days, so what is the hypothesis? Earth slowed down rotation for a while?
I can see two serious problems with that, both pertaining inertia, the law of constant momentum, which doesn't allow for such a slowdown unless you flatten the earth tremendously but that's even weirder. Furthermore what would happen to the loose things on the earth surface and the atmosphere when it would decellerate from say 1000 miles per hour to a few hundred miles. The inertia would cause the atmosphere to continue spinning with the original speed, you would have a world wide storm of several hunderd miles per hour. Unlikely if there would have been survivors.
Considering the earth has an resonance cycle period of something like an hour, if you generate a force on one side of the earth, braking it then it would take an hour or someting before the other side would know about that force while continuing spinning at the original rate. That would cause a break up.
hate to spoil it, but it's rather impossible to find a physically sound mechanism that could cause the Earth temporarily reducing the spin for a day.
Of course there are other possibilities. Super nova? I don't know. main thing is, keep it scientific, observations, physically sound mechanism, test and attempt to refute. Joshuah's long day would not survive scrutiny.
But then again myths are not very accurate observations, are they?
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Baywax
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| Andre wrote: | Wow, that's quite something here.
I googled a bit that's a whole other world it seem
So we have anectdotal evidence that something weird happened to good old Earth. It skipped a day!? But how? Doing something with the rotational axis? Let's see if we can sciencify that (I love inventing new words).
So we have observations of long days, so what is the hypothesis? Earth slowed down rotation for a while?
I can see two serious problems with that, both pertaining inertia, the law of constant momentum, which doesn't allow for such a slowdown unless you flatten the earth tremendously but that's even weirder. Furthermore what would happen to the loose things on the earth surface and the atmosphere when it would decellerate from say 1000 miles per hour to a few hundred miles. The inertia would cause the atmosphere to continue spinning with the original speed, you would have a world wide storm of several hunderd miles per hour. Unlikely if there would have been survivors.
Considering the earth has an resonance cycle period of something like an hour, if you generate a force on one side of the earth, braking it then it would take an hour or someting before the other side would know about that force while continuing spinning at the original rate. That would cause a break up.
hate to spoil it, but it's rather impossible to find a physically sound mechanism that could cause the Earth temporarily reducing the spin for a day.
Of course there are other possibilities. Super nova? I don't know. main thing is, keep it scientific, observations, physically sound mechanism, test and attempt to refute. Joshuah's long day would not survive scrutiny.
But then again myths are not very accurate observations, are they? |
One can only speculate. Myths are stories and reports that have accumulated the opinions and extrapolations and exagerations of each successive story teller over time.
You're right to say that the earth would have basically exploded if there was an abrupt halt of the rotation.
I am of the mind that it could have been another light source occuring after the sun had set. This, as you say, could have been a super nova and/or it could have been a large, luminous body passing close to our orbit.
The long night could just as easily been the same body eclipsing the sun on its way to completely transform Mars.
I've looked into the idea that Mars still had her oceans during the rise of civilization, before 3600 years ago.
The word "Mar" is a word that was borrowed by the Romans from ancient Turkish tribes. Somehow the spanish used the word "mar" to mean "Ocean"... where did that come from? Although today it is translated to mean the god of "War" the our modern translation of the origin of Mars is "rebel" as in "rebelious seas". (my conjecture).
I think that our knowledge about details from the astronomical past is limited because we weren't here.
Our only recourse is to research and cross-reference the accounts and observations there are from that past. Then, as you say, we need to scientifici the data with what we know today of physics, astrophysics and with the knowledge we have of certain possible anomalies we see in the universe today.
A daunting task with little reward.... other than perhaps an inkling of the truth!
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AstrumAspicio
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| Baywax wrote: | | Andre wrote: | Wow, that's quite something here.
I googled a bit that's a whole other world it seem
So we have anectdotal evidence that something weird happened to good old Earth. It skipped a day!? But how? Doing something with the rotational axis? Let's see if we can sciencify that (I love inventing new words).
So we have observations of long days, so what is the hypothesis? Earth slowed down rotation for a while?
I can see two serious problems with that, both pertaining inertia, the law of constant momentum, which doesn't allow for such a slowdown unless you flatten the earth tremendously but that's even weirder. Furthermore what would happen to the loose things on the earth surface and the atmosphere when it would decellerate from say 1000 miles per hour to a few hundred miles. The inertia would cause the atmosphere to continue spinning with the original speed, you would have a world wide storm of several hunderd miles per hour. Unlikely if there would have been survivors.
Considering the earth has an resonance cycle period of something like an hour, if you generate a force on one side of the earth, braking it then it would take an hour or someting before the other side would know about that force while continuing spinning at the original rate. That would cause a break up.
hate to spoil it, but it's rather impossible to find a physically sound mechanism that could cause the Earth temporarily reducing the spin for a day.
Of course there are other possibilities. Super nova? I don't know. main thing is, keep it scientific, observations, physically sound mechanism, test and attempt to refute. Joshuah's long day would not survive scrutiny.
But then again myths are not very accurate observations, are they? |
One can only speculate. Myths are stories and reports that have accumulated the opinions and extrapolations and exagerations of each successive story teller over time.
You're right to say that the earth would have basically exploded if there was an abrupt halt of the rotation.
I am of the mind that it could have been another light source occuring after the sun had set. This, as you say, could have been a super nova and/or it could have been a large, luminous body passing close to our orbit.
The long night could just as easily been the same body eclipsing the sun on its way to completely transform Mars.
I've looked into the idea that Mars still had her oceans during the rise of civilization, before 3600 years ago.
The word "Mar" is a word that was borrowed by the Romans from ancient Turkish tribes. Somehow the spanish used the word "mar" to mean "Ocean"... where did that come from? Although today it is translated to mean the god of "War" the our modern translation of the origin of Mars is "rebel" as in "rebelious seas". (my conjecture).
I think that our knowledge about details from the astronomical past is limited because we weren't here.
Our only recourse is to research and cross-reference the accounts and observations there are from that past. Then, as you say, we need to scientifici the data with what we know today of physics, astrophysics and with the knowledge we have of certain possible anomalies we see in the universe today.
A daunting task with little reward.... other than perhaps an inkling of the truth! |
However, there is a record of the past that stares at us everyday.
Pt-1:
Historically timekeeping and calendars have been tied to the motions found in the heavens. These have been primarily the stars, our Moon, and the Sun. To get a rudimentary understanding of how time is measured and where we got our units of time, we must first talk about the motions of these heavenly bodies referenced back to our Earth. This paper will explore many aspects of the universe, its evolution and the physical properties contained within.
Before we get too far along, I thought we might toss a few definitions up front:
Occam's Razor – one should not make more assumptions than the minimum needed.
Principle of Parsimony – a criterion for deciding among scientific theories or explanations. One should always choose the simplest explanation of a phenomenon, the one that requires the fewest leaps of logic.
Objective – undistorted by emotion or personal bias; based on observable phenomena; "an objective appraisal"; "objective evidence".
Subjective – taking place within the mind and modified by individual bias; "a subjective judgment".
Sophistry – a deliberately invalid argument displaying ingenuity in reasoning in the hope of deceiving someone.
Solipsism (noun), Solipsistic (adjective) – the belief that only one's own experiences and existence can be known with certainty.
Cislunar – situated between the earth and the Moon.
Lagrange Points – places where a light 3rd body can sit "motionless" with respect to 2 heavier bodies that are orbiting each other thanks to the force of gravity. (There are five).
Regolith – The layer of loose rock resting on bedrock, constituting the surface of most land. Also called mantle rock.
Hohmann Transfer Orbit – a Hohmann transfer orbit is the most efficient intermediate orbit to transfer from one circular orbit to another. The transfer orbit is an ellipse with periapsis at the smaller radius and apoapsis at the larger radius.
Delta-V – delta indicates change and V stands for velocity. Change in velocity refers to both the speed of the craft and the direction.
Isp (specific impulse) – The amount of thrust produced from each pound of propellant per second.
Mass Fraction – The mass fraction is a measurement of a rocket’s efficiency. The mass of the propellants of the rocket divided by the total mass of the rocket gives mass fraction.
Planetesimals – A rocky and/or icy body, a few kilometers to several tens of kilometers in size, which was produced in the solar nebula.
Roche Limit – The Roche limit is the minimum distance to which a large satellite can approach its primary body without being torn apart by tidal forces.
Tidal Lock – Tidal drag from one orbiting body on another cause the two bodies to “lock” to each other. This is why the Moon keeps only one side to the Earth.
Angular Momentum – A quantity obtained by multiplying the mass of an orbiting body by its velocity and the radius of its orbit. According to the conservation laws of physics, the angular momentum of any orbiting body must remain constant at all points in the orbit. Thus planets in elliptical orbits travel faster when they are closest to the Sun, and more slowly when farthest from the Sun. A spinning body also possesses spin angular momentum.
Isotope – An element with the same atomic number but having a different atomic weight (i.e. more or less neutrons).
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AstrumAspicio
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Pt-2:
Now that we have a few definitions under the belt, let us continue.
The Celestial sphere:
When we look up at the stars in the night sky they appear to be stationary relative to each other. As the Earth moves from one side of the Sun to the other, the displacement of those stars due to parallax is less than one second of arc even for the nearest star (Proxima Centauri). One way of looking at this is a fixed sphere of stars surrounding the Earth/Sun system. This is often referred to as the Celestial Sphere. This is why some of the ancient civilizations considered the stars to be holes in a tapestry.
Since we are talking distances and parallax, let’s briefly take a moment and describe such. The more familiar term for the layman when referring to stellar distances is called a light year. This is the distance light will travel in one calendar year. For example the closest star to our Sun, Proxima Centauri, is approximately 4.22 light years from our solar system. The light we see from there today was actually generated by that sun 4.22 years ago. Astronomers use another term for stellar distance that may be not so familiar: the Parsec. A Parsec (parallax-arcsecond) is the distance needed for one astronomical unit (AU) to subtend one second of arc. An AU is the average distance from the Earth to the Sun or approximately 93 million miles, and an arcsecond is 1/60 of an arcminute, which is 1/60 of a degree. It turns out a Parsec is about 3.26 light years. Thus for an observer sitting 3.26 light years from the sun, the distance from the sun to Earth’s orbit subtends one arcsecond.
Conversely, an observer on the Earth will see an object positioned one Parsec away appears to shift by up to two arcseconds over the course of a year. If one sighting is made when the line from the Sun to the Earth is 90 degrees from the line of observation, 6 months later the Earth will be on the opposite side of it’s orbit. Since the radius of the Earth’s orbit is one AU, the diameter is 2 AU’s. This change in apparent position from different viewing locations is called parallax.
Proxima Centauri (at 4.22 Light Years or roughly 1.3 Parsecs), shows parallax of about one-and-a-half seconds of arc over the course of a year – too small to be discerned without special high-precision equipment. Most stars are much further away than Proxima Centauri, so for most practical purposes the stars are fixed – at least for periods less than a decade.
Even though it appears the stars remain in “fixed” locations in the night sky, over a period of decades and centuries the stars do move relative to each other and relative to the Earth. The star catalogue based on the epoch B1950 and the one based on the epoch J2000 would reveal minor differences due to these motions.
Another interesting item of note is that the constellations we see are made up of the brightest stars. Even in the same constellation these stars are at vastly different distances from the Earth. Some may be very bright stars that are very distant, and these may appear dimmer than closer stars that are not actually generating nearly as much light. The brightness of a star is called its magnitude. There are two ways astronomers measure magnitude: Apparent Magnitude and Absolute Magnitude.
The Apparent Magnitude is how bright a star appears to us here on the Earth. The Absolute Magnitude is how bright a star would appear if it were exactly ten parsecs away from the Earth. (Close to 33 light years).
Two notes:
1) Apparent magnitude is usually denoted with a small “m” and absolute magnitude uses a capital “M”.
2) The magnitude scale is backwards of what you might think: the larger the number the fainter the object. The brightest star is Sirius with magnitude of –1.5m, while somewhat dimmer Vega is defined as 0m, and planet Venus may become as bright as –4.4m. The typical human eye can just barely see a star with a magnitude of +6m, but Earth-based telescopes may see stars as dim as +18m, and the Hubble can see stars as feint as +30m.
The Ecliptic Plane:
Since the Earth is tilted (23.5 degrees) in reference to the path it sweeps out in its orbit about the Sun, this path projected onto the celestial sphere does not fall on the celestial equator. This imaginary plane is called the ecliptic. Note: This angle between the ecliptic and the equatorial plane is called The Obliquity of the Ecliptic.
This imaginary plane crosses the celestial equator in two places (called the equinoxes). The Vernal Equinox falls in the spring as the Sun appears to cross the ecliptic going north and the Autumnal Equinox falls in autumn when the Sun again crosses the ecliptic, this time going south. Note: Vernal comes from the Latin vernalis, meaning spring. Also the term equinox relates to the word equal since both day and night are close to the same, 12 hours during the equinox.
The points where this plane is the farthest above (north) and below (south) the celestial equator is called the solstices. In the northern hemisphere of the earth, the most northern point of the ecliptic is called the Summer Solstice and the southern most is called the Winter Solstice. In the Southern hemisphere of the Earth the reverse is true.
The zodiac lies along the plane of the ecliptic. Since the Earth is orbiting the Sun, the Sun appears to follow the plane of the ecliptic, making one complete circle in one calendar year. The name “zodiac” comes from the Greek meaning animal circle. In fact all of the 12 constellations of the zodiac are named after animals. Note: The path of the Moon and the other planets fall pretty much on this plane as well. Since it takes 365 days for the Earth to orbit the Sun and there are 360 degrees in a circle, the Sun moves pretty close to 1 degree per day.
Celestial Coordinates:
If, on the first day of spring (the Vernal Equinox), a line is drawn from the Sun through the Earth and out to infinity, that line is said to extend to a point referred to as The First Point of Aries. (So named because at one time this line pointed to the first star in the constellation of Aries)
The celestial sphere is tied to the Earth for its coordinate system. Project the Earth’s equator out to infinity and you have the equator of the celestial sphere. Likewise the north and south poles of the Earth points to the north and south poles of the celestial sphere respectively. This makes it very easy to map the sky referenced to the Earth. This coordinate system is called the Equatorial Coordinate System. It ties in closely with our own geographic coordinate system here on the surface of the Earth.
Note, however, the geographic coordinate system is fixed upon the surface of the Earth (Lat-Long) -- so it rotates with the rotation of the Earth. The celestial coordinate system is fixed to the celestial sphere and appears to rotate due to the Earth’s rotation. The equivalent of “latitude” in the celestial sphere (the angle of an object above or below the celestial equator) is called declination, with zero being on the equator. (This is pretty easy to relate to, since the celestial’s equator and poles appear to be fixed like our own earth.) The celestial sphere’s analog to “longitude”, called right ascension, and is not a “fixed” reference to the Earth. It is fixed to the stars instead, thusly rotating every 24 hours. Instead of using degrees, right ascension is measured in hours minutes and seconds. The Vernal Equinox is used as the zero reference for the right ascension. Since there are 360 degrees in a circle, the Earth rotates about 15 degrees every hour, so every hour of right ascension is equivalent to 15 degrees.
A declination of zero is on the equator and a right ascension of zero is at the Vernal Equinox. So on the first day of spring, when the Earth’s equator lines up with the line to the First Point of Aries, the Vernal Equinox will have the coordinates of 0 degrees and 0 hours. This has come to define the center point for an Equatorial Sky Chart
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AstrumAspicio
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Pt-3:
On to the Earth-Sun system:
It takes one year for the Earth to rotate around the Sun one time and 24 hours to rotate on its axis. Think about this relationship. Not only is the Earth revolving on its axis, it is in motion about the Sun. (I know this is really basic grade school stuff, however, it will help in visualizing the concepts I am about to explain) Therefore the Earth moves 1/365th of its orbit about the Sun every day.
Ok, here is where that visualization will come in handy. Since a “day” is described by one complete rotation of the Earth on its axis, this equates from noon to noon (when a point on the Earth is directly pointed at the Sun). The term for this is called the Mean Solar Day. But here is the rub; the Earth has moved through 1/365th of its orbit during this period of time we called a day. Because the Earth has moved over a tiny bit from where is was the day before, it must rotate a tiny bit more to have the same spot facing the Sun at noon. This tiny bit is slightly less than one degree (the Earth’s orbit completes 360 degrees in 365 days). Thus the Earth actually rotates almost 361 degrees, not just 360, to complete a mean solar day.
Now let us think of this celestial sphere we have been chatting about. Remember the stars appear fixed in one location (at least on a daily basis). This means that one complete revolution of the Earth referenced to a star does not take that little bit of extra time to be over the same spot on the Earth. This “day” is referred to as a Sidereal Day. It takes approximately four extra minutes for the Earth to have the Sun over the same location on the Earth than a star.
This is the difference between a Sidereal Day (23 hours, 56 minutes) and a Mean Solar Day (24 hours).
Also the Earth is tilted on its axis from the plane of the ecliptic by 23.5 degrees. That tilt causes the North Pole to be currently pointed towards Polaris. As the Earth moves around the sun its pole stays pointed at Polaris. This is the cause of the seasons we experience. Note. This tilt varies back and forth from 21.6 degrees to 24.5 degrees approximately every 41,000 years.
There is also a precession of our pole and it sweeps a complete circle in the sky (think of the Earth as a top wobbling as it rotates) about every 26,000 years. This gives us different pole stars as the north pole of the Earth sweeps out a circle on the celestial sphere.
There are also a number of other motions that must be taken into consideration over the years, such as the precession of the aphelion. Our Earth’s orbit around the Sun is not a perfect circle. It is an ellipse with the closest point of the orbit called perihelion and the furthest point called aphelion. Currently perihelion occurs in early January, and aphelion falls in early July. However, this is not always the case. The aphelion and perihelion change over the centuries and sweeps thru the calendar year with a periodicity of around 22,000 years. By the way, the amount a circle is “squished” to create an ellipse is called its eccentricity. If the eccentricity is equal to zero the orbit will be a perfect circle (also known as a degenerate ellipse). An eccentricity between zero and one, not inclusive, describes the elliptical path of an orbit – a highly eccentric orbit has eccentricity close to one. In the case of eccentricity equal exactly to one, the path is a parabola, and eccentricity greater than one describes a hyperbola. Although natural forces tend to circularize most orbits over time, achieving an eccentricity of exactly zero is extremely unlikely in nature.
The eccentricity of Earth’s orbit is very small. However, even this changes over time. Its eccentricity varies periodically about every 100,000 years. There are also other motions affecting the orbit, caused by the Moon, Jupiter and the Sun: these are called Nutations. One of the major nutations has a period of 18.6 years.
This cursory look at the Time-Earth-Sun finally leads is into a discussion of the Earth-Moon system where I was driving to in the first place.
Whew! Time to get some coffee.
(hope I am not being too wordy so early on)
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AstrumAspicio
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Pt-4:
Ok, let us take a look at the Moon:
Currently, the evidence points to a catastrophic collision of another body with the Earth not long after the formation of the Earth. This collision is what is believed to have formed the Moon. Originally the Moon was much closer to the Earth and its period did not match its rotation. Over the years the Moon has become tidally locked with the Earth resulting in the Moon keeping one face to the Earth (Its rotation on its axis matches the period of its orbit). This tidal locking will eventually cause the Earth and Moon to keep one face to each other since the Earth is affected by tides as well. (However, under current stellar evolutionary theory, the Sun will go nova before this happens) A more in-depth discussion of this is continued in the following paragraphs.
Some of the following questions;
1) How was it formed?
2) What is it made of?
3) How far away is it?
We are now gaining the knowledge to be able to answer (at least in part).
1) How was the Moon formed?
There were at least five major ideas that were proposed as to the formation of the Moon.
Fission – The Moon split off from the Earth.
Capture – The Moon was captured by the gravity of the Earth.
Condensation – The Moon coalesced out of the same “stuff” the Earth did.
Colliding Planetesimals – Formed from colliding Planetesimals during the early formation of the solar system.
Collision – A body collided with the Earth causing a piece of the Earth’s crust to form the Moon from a resultant ring produced by that collision.
The evidence points to the collision theory. First, the Moon does not have an iron core. This pretty much rules out that it coalesced from the same cloud of debris that the Earth did. Second, throughout the solar system, the oxygen isotopes have been found to be different. If the Moon were captured, it too would not match the Earth’s oxygen isotope ratio (which it does). Fourth, by looking at the angular momentum and energy required, the theory that the Moon spun off the Earth after the Earth formed does not hold up.
This leaves us with the Collision theory as the best model we have for the formation of the Moon. The resultant collision caused a ring of debris from the Earths crust to form outside the Roche limit. If it had not, tidal forces would have not allowed for the Moon we see today.
A more in depth discussion of tidal locking since the Moon is tidal locked to the Earth. The reason the Moon keeps one face to the Earth (Its rotation on its axis matches the period of its orbit) is it is tidally locked to the Earth. Here is a more in depth explanation. The total angular momentum of the earth moon system, which is spin angular momentum plus the orbital angular momentum, is constant. (The Sun plays apart also) Friction of the oceans caused by the tides is causing the Earth to slow down a tiny bit each year. This is approximately two milliseconds per century causing the moon to recede by about 3.7 centimeters per year. As the Earth slows down, the Moon must recede to keep the total angular momentum a constant. In other words as the spin angular momentum of the earth decreases, the lunar orbital angular momentum must increase. Here is an interesting side note. The velocity of the moon will slow down as the orbit increases.
Another example of tidal locking is the orbit period and rotation of the planet Mercury. What is interesting about this one is that instead of a 1:1 synchronization where Mercury would keep one face to the Sun at all times, it is actually in a 2/3:1 synchronization. This is due to the High eccentricity of its orbit.
There also can be more than one body “locked” to each other. Let’s take a look at the moon Io. Io is very nearly the same size as the Earth’s moon. It is approximately 1.04 times the size of the moon. There is a resonance between Io, Ganymede, and Europa. Io completes four revolutions for every one of Ganymede and two of Europa. This is due to a Laplace Resonance phenomenon. A Laplace Resonance is when more than two bodies are forced into a minimum energy configuration.
There are also examples of tidal locking in the asteroid belt.
First, the asteroid belt has an estimated total combined mass of less than 1 tenth of the Earth's moon. Second, Jupiter has a profound effect on the asteroid belt.
Since Jupiter has a semimajor axis of 5.2 AU (I AU is the distance from the Sun to the Earth) it ends up with an orbital period of 11.86 years. Since the asteroids are not all at the same distance from the sun, there orbital periods will differ in a direct relationship to their distance from the sun. This will result in some of them having an orbital period of one half of Jupiter. This puts those particular asteroids in a 2:1 orbital resonance with Jupiter. The result of this resonance is gaps called Kirkwood's gaps.
The rub is why did not this asteroid belt form a small planet? The reason is the gravitational force of Jupiter. It perturbs the asteroids giving them random velocities relative to each other.
Another effect of both Jupiter and the Sun on the asteroid belt is a group of asteroids that both precede and follow Jupiter in its orbit by 60 degrees. These asteroids are known as the Trojans.
2) What is the Moon made of?
From here:
http://lunar.arc.nasa.gov/science/geochem.htm
Primary elements: The lunar crust is composed of a variety of primary elements, including uranium, thorium, potassium, oxygen, silicon, magnesium, iron, titanium, calcium, aluminum and hydrogen. When bombarded by cosmic rays, each element bounces back into space its own radiation, in the form of gamma rays. Some elements, such as uranium, thorium and potassium, are radioactive and emit gamma rays on their own. However, regardless of what causes them, gamma rays for each element are all different from one another -- each produces a unique spectral "signature," detectable by an instrument called a spectrometer. A complete global mapping of the Moon for the abundance of these elements has never been performed.
Hydrogen and helium: Because its surface is not protected by an atmosphere, the Moon is constantly exposed to the solar wind, which carries both hydrogen and helium -- each potentially very valuable resources. One natural variant of helium, [3]helium, is the ideal material to fuel fusion reactions. When scientists develop a more thorough understanding of fusion, and can practically implement such reactions, the Moon will be a priceless resource, since it is by far the best source of [3]helium anywhere in the Solar System.”
This pretty much answers the question; are there valuable materials up there?
3) What is the distance to the Moon?
The mean distance to the Moon is approximately 238,800 miles. From past experience, we can design spacecraft to get there in about three days. This is far shorter than the months the early voyages took to the new world.
Final thoughts on the Moon:
So here we have this tremendous resource at our fingertips. Unfortunately (not unlike the early explorers), the initial cost is staggering. However, in the long run it would end up being an invaluable resource for both material and scientific study. One of the big advantages is that the Moon keeps one side facing the Earth. This minimizes communication problems between the two bodies. Also since the backside of the Moon is shielded from the Earth, it would be an ideal spot to place a radio telescope array.
Since we are now talking about orbiting bodies, let us digress just a wee bit further and briefly talk about orbits:
There are different sizes and shapes of orbits. We use the term Semi-Major Axis to measure the size of an orbit. It is the distance from the geometric center of the ellipse to either the apogee or perigee (The highest (apo) and the lowest (peri)). Apoapsis is a general term for the greatest radial distance of an Ellipse as measured from a Focus. Apoapsis for an orbit around the Earth is called apogee, and apoapsis for an orbit around the Sun is called aphelion.
Periapsis is a general term for the smallest radial distance of an Ellipse as measured from a Focus. Periapsis for an orbit around the Earth is called perigee, and periapsis for an orbit around the Sun is called perihelion.
The terms Gee and Helios comes from the Greek words “Ge” (earth) and “Helios” (Sun) respectively.
First lets talk a bit about “where it is”. An orbit is a nothing more than an object falling around another object. Both Kepler and Newton came up with a set of laws that describe this phenomenon.
Kepler’s three laws of planetary motion:
1) The orbit of a planet is an ellipse with the sun at one of the foci
2) The line drawn between a planet and the sun sweep out equal areas in equal times.
3) The square of the periods of the planets is proportional to the cubes of their mean distance from the sun.
So what is that telling us? In a nutshell, all orbits are ellipses, the close to the body you are orbiting the faster you go (e.g. if you have a highly elliptical orbit the satellite or planets velocity will increase as it approaches the object being orbited and decrease as it get further away)
These laws not only apply to planets and satellites, but to any orbiting body.
Note: Super geek alert:
-For an orbiting body this is not entirely correct. It turns out that both bodies end up orbiting a common center of mass of the two-body system. However, for satellites, the mass of the Earth is so much greater than the mass of the satellite, the effective center of mass is the center of the Earth.-
Newton’s three laws (and law of gravitation):
1) The first law states that every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force. (Commonly known as inertia).
2) The second law states that force is equal to the change in momentum (MV) per change in time. (For a constant mass, force equals mass times acceleration F=ma).
3) The third law states that for every action there is an equal and opposite reaction. In other words, if an object exerts a force on another object, a resulting equal force is exerted back on the original object.
Newton’s law of gravitation states that any two bodies attract one another with a force proportional to the product of their masses and inversely proportional to the square of the distance between them.
Note: Super geek alert #2:
-Actual observed positions did not quite match the predictions under classical Newtonian physics. Albert Einstein later solved this discrepancy with his “General Theory of Relativity”. -
There are four classical “tests” that cemented General Relativity:
1) In November of 1919, using a solar eclipse, experimental verification of his theory was performed by measuring the apparent change in a stars position due to the bending of the light buy the sun’s gravity.
2) The changing orientation of the major axis or Mercury not exactly matching classical mechanics.
3) Gravitational Redshift.
4) Gravitational Time Dilation.
So what is all this trying to tell us? Planets, satellites, etc orbit their parents in predictable trajectories allowing us to “know” where they will be at any given time. A set of coordinates showing the location of these objects over a period of time is called its ephemeris.
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AstrumAspicio
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Pt-5: (WHEW LAST PART) Hope I was not too bold in posting so much all at once)
FINALLY let go back to the beginning of my screed (LOL) and talk about time keeping and leap seconds!
Historically, time has been measured by the rotation of the Earth on its axis and the time it takes to rotate once about the Sun (a year). However, both of these are not uniform enough for precise calculations.
One of the units of time is called the second. It used to be defined as 1/86,400 of a Mean Solar Day. This was good enough for early calculations, but don’t forget that the Earth is slowing down due to tidal forces so that ends up changing over time. After a number of intermediate steps the second was finally redefined as:
-The duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom. (Atomic time); also known as Coordinated Universal Time (UTC).-
Since the Earth is slowing down approximately 1.4 milliseconds per day per century, this deceleration causes the Earth’s rotational time to vary from atomic time. The current true (instantaneous) rotation rate of the Earth is called UT1 (which is a non-uniform rotation). Over a period of a year the difference between it and UTC can approach a full second. However, since the Earth’s rotation is non-uniform, it is monitored continuously. If the difference between UT1 and UTC approaches 0.9 seconds, a leap second is added or subtracted from UTC to keep it uniform with the Earth’s rotation. So far all of the leap seconds have been positive. This correlates with the Earth slowing due to tidal braking.
Note: Since the GPS time does not have leap seconds added or subtracted, it is diverging with UTC with every second added to UTC. Currently it is different by 14 seconds. This can cause some consternation when flying a satellite or spacecraft that uses GPS. If your ephemeris is calculated in GPS time and you receive a “vector” in UTC time, it will be off by 14 seconds. You just cannot add 14 or subtract 14 seconds and press on. The rub is that not only has the satellite moved 14 seconds in-track, the Earth has rotated underneath by 14 seconds (cross-track) as well. This is especially noticeable for the high inclination orbits. Vectors have to be recalculated when translating between GPS and UTC.
Remember, the deceleration of the Earth is not uniform. There may be a number of factors that cause this non-linearity such as snow and ice loads, earthquakes and others we haven’t even thought of. This could account for the variations between leap seconds requirements that we have experienced in the past. However, the Earth will continue to slow down and the deceleration will still vary.
One final item: There is an ongoing debate whether to do away with leap seconds all together and just go with UTC. The problem with this is, over an extended period of time, the hours will no longer be tied to the solar day and noon may well end up in the evening. Another suggestion is to redefine the period of one second to more closely match the current rotation of the Earth. This too has its problems as the second will required “redefining” periodically as the Earth continues to slow down.
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NileQueen
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| AstrumAspicio wrote: | Pt-5: (WHEW LAST PART) Hope I was not too bold in posting so much all at once)
FINALLY let go back to the beginning of my screed (LOL) and talk about time keeping and leap seconds!
Historically, time has been measured by the rotation of the Earth on its axis and the time it takes to rotate once about the Sun (a year). However, both of these are not uniform enough for precise calculations...
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Fossil clocks have been used to demonstrate earth's slowing down over time,
but how would we show any loss in LOD in more recent geological time, since LGM, if that had occurred?
Would LOD have been different with much lower sealevels during the last ice age? The mass would have been in the LIS GIS and SIS which would have created quite some change in elevation. Continental shelves would have been exposed and tides perhaps different...
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Baywax
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AstrumAspicio,
your amazing perseverence in enlightening us about planetary evolution, orbit and physics is astounding! This is the kind of background that I am missing when I come in, guns blazing, asking about Velikovsky 's and Clarke's suppositions concerning Venus, Jupiter and Mars. I can only hope you'll address some of these questions and utilize your stellar understanding of planetary mechanics to further disclose what may be the truth about these ideas.
I fully understand the peril of emotional, personal and other motivational influences that can obscure the truth. I welcome any concrete evidence that supports or detracts from past speculations such as the idea that Venus was extracted from Jupiter (somehow) setting the stage for some of the features we see in the solar system today. But believe me I'm not an astronomer.
During 12 years in Physical Anthropology I've often relied on reports, stories and myths to guide me to physical truths about the past. And I haven't been disappointed very often. That's why I've lent some credence to certain aspects of Velokovski's and other's use of similar research methodologies.
Thank you!
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Baywax
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This was thought to be the birth place of Venus by Velikovsky. Out of the "Great Red Spot"
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Baywax
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Messenger and Venus Express compile data on clouds etc.... during a duel orbit of Venus, July 19/07
http://www.esa.int/SPECIALS/Venus_Express/SEMVN4HYX3F_0.html
| Quote: | Neith, the Moon of Venus, 1672-1892
In 1672, Giovanni Domenico Cassini, one of the prominent astronomers of the time, noticed a small companion close to Venus. Did Venus have a satellite? Cassini decided not to announce his observation, but 14 years later, in 1686, he saw the object again, and then entered it in his journal. The object was estimated to have about 1/4 the diameter of Venus, and it showed the same phase as Venus. Later, the object was seen by other astronomers as well: by James Short in 1740, Andreas Mayer in 1759, J. L. Lagrange in 1761 (Lagrange announced that the orbital plane of the satellite was perpendicular to the ecliptic). During 1761 the object was seen a total of 18 times by five observers. The observations of Scheuten on June 6 1761 was especially interesting: he saw Venus in transit across the Sun's disk, accompanied by a smaller dark spot on one side, which followed Venus in its transit. However, Samuel Dunn at Chelsea, England, who also watched that transit, did not see that additional spot. In 1764 there were 8 observations by two observers. Other observers tried to see the satellite but failed to find it.
In 1768 there was one more observation of the satellite, by Christian Horrebow in Copenhagen. There were also three searches, one made by one of the greatest astronomers of all time, William Herschel -- all three of them failed to find any satellite. Quite late in the game, F. Schorr from Germany tried to make a case for the satellite in a book published in 1875. |
mystery continues at.....
http://www.nineplanets.org/hypo.html#neith
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AstrumAspicio
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1st - my apologies for such a huge data dump on your site. I tend to get carried away.
2nd - I am putting a post together (much smaller) showing why Venus did not originate from Jupiter in the past few thousand years.
-M-
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Baywax
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| AstrumAspicio wrote: | 1st - my apologies for such a huge data dump on your site. I tend to get carried away.
2nd - I am putting a post together (much smaller) showing why Venus did not originate from Jupiter in the past few thousand years.
-M- |
Thank you AstrumAspicio.... I'm doing a search to see if there are records of Venus from beyond 3600 years ago.
From a paper for the Royal Astro Soc by the Rev. S.J. Johnson, M.A. of Melplash vicarage, Bridport and dated Nov 7, 1882:
| Quote: | A broken Assyrian tablet... concerned with the planet Venus, and as the following succession of lines occurs, "the planet Venus"---"it
passed accross"---"the Sun"---"across the face of the Sun," it
naturally occurs to try to fill up each hiatus. But it seems very
difficult to explain the last sentence otherwise than by supposing
that an actual transit is recorded, which, it seems must be before the
sixteenth century B.C. It reads like a case of an entire transit
visible from Babylonia. |
This is an unreliable report. 1. Could the Assyrians sustain an observation of a transit without proper ocular protection (smoked glass)?. 2. How do we date the record (tablet) properly. 3. "Passed across the sun" can also mean eclipsed the sun or was in transit from Jupiter to its present orbit (as was suppositioned earlier).
I can't seem to find any other records that suggest venus was recorded as a celestial body from before and even long after 1600 BC. The NASA Venus tables end at the above account by Rev. S.J. Johnson M.A.
I'd be interested to read your astrophysics on the subject!
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Baywax
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Another tid bit from pre-history (no actual date) about Venus.
An oral-traditional story from Tanzania (tends to support the idea that Venus "visited earth" and carried on its way afterwards)
| Quote: | Kileken (sometimes Kileghen) is the subject of a myth of the Maasai people concerning the planet Venus.
In the myth, the planet Venus is called Kileken, and visits the Earth in the form of a small boy. The boy befriends an old farmer and tends his cattle, the man agreeing to let the boy keep the only thing he has: the secret of his origin.
When the man betrays his trust and spies on Kileken, the boy vanishes in a bright light and returns to the heavens. The oral tradition was captured in a book by the Tanzania-born author Tololwa M. Mollel. |
http://en.wikipedia.org/wiki/Kileken
This story is also sometimes called "The Orphan Boy".
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Baywax
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In defence (of using folklore and ancient records) I have to point out that the only records of the Super Nova that created the Crab Nebula are derived from the 1000 year old observations and suppositions of ancient cultures. Here are some of the accounts..... and they don't sound all that different from the accounts I've given of the "long day", the "long night" or what was even called "Venus visiting Earth".
| Quote: | Supernova. In July 1054, a star could be seen blazing in the heavens. For three weeks it was so bright it could be seen in daylight. The only reason we know of it today is because Arab, Chinese, Japanese and Native American astronomers noted it. That supernova created what we now call the Crab Nebula.
China. Chinese astronomers wrote about a "guest star" in the constellation Taurus that became four times brighter than Venus and was visible in daylight for 23 days. The yellow colored "guest star" was visible to the naked eye at night for 653 days.
Anasazi. It is thought to have been recorded in pottery by Anasazi Indian artists living on land we now call Arizona and New Mexico, and by the Mimbres Indians of New Mexico.
Fujiwara. A Japanese poet Sadiae Fujiwara wrote about the star Zeta Tauri.
Euro tune out. European astronomers apparently took no interest, or at least no records of European or Arab observations of the 1054 supernova have survived to modern times. |
http://www.spacetoday.org/SolSys/Earth/AncientAstronomy.html
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Baywax
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Please bear with me as I expose another myth that points to Venus as being expunged from Jupiter around 3600 years ago.
This is to hold this thread over until someone can show us the astrophyics that will completely rule this sort of claim out (which was originally made by Velokovski (sp).)
Going with Greek mythology, Zeus gave birth to [Venus] when he had a very terrible headache, so terrible he split his head open, and out popped [Venus].
Venus is associated with Lucifer and Satan in folklore and mythology...."Lucifer, how you have fallen, cast out of the Heavens"... can be read as a celestrial event, something grand happening in the stary nights, something so big that people took notice and felt afraid...
....Especially when they didn't have Dolby Surround Sound or THX or HD or BlueRay discs in boxes blasting the **** out of they're homes every night! They weren't used to big, flashy occurances as this one might have been.
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Andre
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Interesting, BW, Thanks,
Obviously there have been spectacular cosmic displays in the night sky, causing all kind of specultations by the spectators, ultimately resulting in those myths.
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Baywax
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Thanks Andre,
To me, she still looks pretty young!
http://www.universetoday.com/2007.../messengers-farewell-venus-video/
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scpg02
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| Quote: | | To me, she still looks pretty young! |
Thank you.
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Andre
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| scpg02 wrote: | | Quote: | | To me, she still looks pretty young! |
Thank you.  |
Okay, I'm getting the message. Don't take a sip of coffee when opening the earth forums. When Maggie posts, you may have to clean out the keybord from the coffee.
Such a spill.
Anyway, i don't know how to put it. i'm sure that Maggie looks great, but this is how that particular planet looks like naked:
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Baywax
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That's the infared shot of her, yes. They call some of the blotches impact craters and some of them volcanic sites. More like an adolescent portrait of her surface.
Its hard to tell what's going on in that photo. Eruptions or very few impacts....... (possibly residual scars from an encounter with Mars)... all in all she's still young with all that "magma" still flowing!
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Andre
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| Baywax wrote: | That's the infared shot of her, yes. They call some of the blotches impact craters and some of them volcanic sites. More like an adolescent portrait of her surface.
Its hard to tell what's going on in that photo. Eruptions or very few impacts....... (possibly residual scars from an encounter with Mars)... all in all she's still young with all that "magma" still flowing! |
Well there are dozens of people devoting their useful life to try and explain Venus with logic, the impact craters for instance:
http://jove.geol.niu.edu/faculty/stoddard/TEXT/matiasetal.pdf
http://jove.geol.niu.edu/faculty/stoddard/TEXT/penrose2003.pdf
http://www.mantleplumes.org/Penro...okChapterPDFs/Matias_Accepted.pdf
http://www.galaxy.gmu.edu/interfa...ckSteven/HauckSteven.abstract.pdf
http://www.galaxy.gmu.edu/interfa...dings/HauckSteven/HauckSteven.pdf (big file)
perhaps it would be prudent to falsify that first before speculating on wild rides.
I just happen to notice on slide 23 on the last one:
| Quote: | The big question
What does it mean for the evolution of a planet if the spatial distribution of impact craters on its surface cannot be distinguished from a completely spatially random distribution? |
Compare it with Mars on slide 16 with the highest impact density around the equator. Would it mean that the big answer is that this is due to the chaotic zone, causing the planet to spin at random also exposing the current polar areas to impacts when spinning highly oblique.
Rather consistent with a certain pet idea.
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Baywax
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These articles look really good Andre.
The PPT is good and to the point.
There appears to be remaining undecidedness about Venus and her whole morphology, history etc......
You may still sway me to believe that craters can be used as a dating technique. But I will have to find some stuff about that on my own....
here's something of interest concerning the controversy surrounding the age and morphological structure of Venus's surface,
| Quote: | Models for the surface age of Venus can be considered as lying in between two extreme, or end-member models. In one extreme, the crater data can be interpreted to indicate that all significant geologic activity ceased on Venus as of 300--500 Ma (million years ago), and that prior to that time, activity was rapid and no craters from this previous epoch survive on the surface today. The other end-member model suggests that geologic activity is ongoing and that no steep decline in rates of tectonism and volcanism is required.
Noting the spatial randomness and the unmodified appearance of impact craters, Schaber et al. [1992; also Strom et al., 1994] suggest that they represent a production population, one that has undergone little or no modification due to volcanism or tectonism. Prior to Ma, they suggest that the rate of volcanic and tectonic activity was high in comparison to the cratering rate. This activity constitutes global resurfacing, and may be a recurring event in Venus history [ Arkani-Hamed et al., 1993; Parmentier and Hess, 1992]. Subsequent to resurfacing was a short period (approximately 10 m.y.) of steep decline in the rate of geologic activity. Geologic activity since the end of this ``great decline'' has been comparatively minor.
Phillips et al. [1992] argue against an end-member global resurfacing model for reasons that involve spatial correlation of modified craters with geological features or with one another. These workers formulated an equilibrium resurfacing model which considered a characteristic area and recurrence interval for resurfacing events. The model only satisfies the requirement of spatial randomness for events covering less than 140,000 km (0.03% of Venus' surface) that recur at intervals of less than 150,000 years or for events covering more than 10% of the planet ( km) |
http://www.agu.org/revgeophys/bindsc01/node2.html
Its interesting to note that there are questions surrounding the volcanism and the craters and the age of the surface in general. The craters show no signs of disturbance yet there are active flows everywhere. The photos of the craters are astounding and the debris fields are almost symetrical with a very "fresh" look to them.
Dating Craters (during high school )
| Quote: | | We suggest a crater dating technique that correlates morphometric indices of simple impact craters to their age. We examine populations of craters from several Martian terrains of known age and, using the Mars Orbiter Laser Altimeter (MOLA) topographic dataset, we compute their rim-to-diameter ratio, depth-to-diameter ratio, slope, and eccentricity. Since these parameters will be systematically affected by the degree of degradation by erosional and depositional processes, they can be useful metrics for characterizing crater degradational process and also for estimating crater age. By considering the youngest surfaces on Mars, those of Amazonian age (< ca. 250 Ma), and sequentially examining surfaces of progressively older age (e.g. Herperian and Noachian), we characterize age populations of simple craters according to their degradational morphology. This is then used to calibrate a model for the degradational history of simple craters on Mars that can be used for geochronologic purposes. In addition, we can use the data to estimate the density of craters (craters/km2) of a given size and age expected on a surface. The applications of this statistical study of crater morphology include planetary geochronology and the identification of resurfacing events. |
http://adsabs.harvard.edu/abs/2006AGUFM.P31B0146C
| Quote: | | "We examine populations of craters from several Martian terrains of known age |
How does someone arrive at the "known age" of a terrain on Mars? And how does that "known age" help date a crater on the other side of the planet or even a few km from the "known terrain"??
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Andre
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I think this the key paper here:
http://adsabs.harvard.edu/abs/1998JGR...103.8531B
Basilevsky, A.T. Head, J.W. 1998 The geologic history of Venus: A stratigraphic view: Journal of Geophysical Research, Volume 103, Issue E4, p. 8531-8544
| Quote: | Abstract
On the basis of regional and global stratigraphic analyses, we outline the major events in the geologic history of Venus determined by photogeological study of surface features. Because the morphological signatures of terrain emplaced prior to the time of tessera formation are not preserved, the stratigraphic record presented comprises only the last 10-20% of the total history of Venus. The estimated range of the mean crater retention age of the surface (from ~200 to 1600 million years) leads us to describe the timing and duration of different events in terms of fractions of the mean surface age T. The beginning of the observed history of Venus was characterized by intensive tectonic deformation of global or semi-global scale which formed the tessera terrain. Termination of the compressional stage is estimated to have occurred at about 1.4T while the tensional stage lasted for another 0.1-0.2T. After tessera formation, several stages of extensive volcanism occurred, burying vast areas of tessera and forming what are now observed as regional plains. The combined duration of the emplacement of these plains is estimated to be about 0.2-0.3T, with an implied average global rate of volcanism of a few cubic kilometers per year. Regional plains-forming materials can be subdivided and are separated from each other, and from underlying and overlying units, by unconformities. These unconformities are formed, from oldest to youngest, by tessera-forming deformation, dense fracturing, broad ridging, and, finally, wrinkle ridging. These tectonic episodes are interpreted to be generally globally synchronous and to represent successive episodes characterized by the dominance of compression, then tension, then again compression, and, finally, tension. The last global-scale tectonic episode, extensive wrinkle ridging, happened at about time T, which was very close in time to the emplacement of the most areally abundant plains unit. This marked the transition to the present stage of the history of Venus, which is characterized by a predominance of regional rifting and related volcanism. This stage appears to have lasted from about time T to the present, making it the longest time duration among the stratigraphic units considered, although the resulting tectonic and volcanic features and deposits cover only 10-20% of the surface of Venus. These observations mean that the general intensity of tectonics and the flux of volcanism (a few tenths of a cubic kilometer per year) in this latest period were much lower than those in earlier times. In summary, the morphologically observable part of the history of Venus was characterized by two key characteristics that stand in contrast to the comparable period of Earth history (approximately the Phanerozoic) when global geodynamic processes were dominated by plate tectonics: (1) Venus shows no signature of plate tectonics; instead, its global tectonic environment passed from an initial dominance of compression, through tension, then again compression, and finally tension, with the density of deformational structures and the strain rate declining with time. (2) In the beginning of this period of time on Venus, plains-forming volcanism occurred at a rate comparable to volcanism at mid-ocean ridges but was emplaced in an entirely different style. The predominant component of volcanism on Earth during this time was the extrusive volcanism at mid-oceanic ridges. For the last few hundred million years, Venus has been dominated primarily by rift-associated volcanism emplaced at a production rate comparable to or even lower than present intraplate volcanism production rates on Earth. |
It's interesting what T is exactly, 500My or 1By, the ratio of event. Note the declining volcanism and other activities. Seen a PhD thesis on the impact craters, the freshness, lava filling etc. Only a few are. Therefore it is thought that the volcanism declined overall. This is exactly in line with my little pet idea that is a bit in the freezer right now. But it will come out again when the Venus express acknowledges that.
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Baywax
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You're rapidly deflating any possibility of Venus being 3600 years old... ... at least by siting these damn Harvard fellows....
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Andre
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I'm sorry about that. That extremely effective Magellan radar imaging satellite spoiled the romantic musing about Venus. Well science progresses and we have to move on I guess.
I'd like to explore that later after the isotopes.
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Baywax
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Its ok Andre... you always seem to come up with good evidence!
I am still somewhat optimistic, given how researchers and instruments and interpretations can be incorrect. For instance with the fact that
| Quote: | | There are few impact craters on Venus, suggesting that the surface is, in general, geologically young - less than 800 million years old. |
http://www2.jpl.nasa.gov/magellan/fact.html (your source)
this "less than 800 million years old" could be as young as 3600 years old.... in literal terms....
In the model of Venus being expunged from Jupiter we have to remember that the interior of Venus would be as old as Jupiter while the surface would appear "young" as has been demonstrated.
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Baywax
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Here is a summary of Immanuel Velikovsky's theories concerning Venus, Jupiter, Earth, Mars and the record of events that allegedly took place between these planetary bodies.
| Quote: | Immanuel Velikovsky has a theory about (Jupiter/Venus) in his book Worlds in Collision......
Core ideas
"Worlds in Collision is a book of wars in the celestial sphere that took place in historical times. In these wars the planet earth participated too. [...] The historical-cosmological story of this book is based in the evidence of historical texts of many people around the globe, on classical literature, on epics of the northern races, on sacred books of the peoples of the Orient and Occident, on traditions and folklore of primitive peoples, on old astronomical inscriptions and charts, on archaeological finds, and also on geological and paleontological material." - Worlds in Collision, Preface.
The book proposed that around the 15th century BC, a comet or comet-like object (now called the planet Venus), having originally been ejected from Jupiter, passed near Earth (an actual collision is not mentioned). The object changed Earth's orbit and axis, causing innumerable catastrophes which were mentioned in early mythologies and religions around the world. Fifty-two years later, it passed close by again, stopping the Earth's rotation for a while and causing more catastrophes. Then, in the 8th and 7th centuries BCE, Mars (itself displaced by Venus) made close approaches to the Earth; this incident caused a new round of disturbances and disasters. After that, the current "celestial order" was established. The courses of the planets stabilized over the centuries and Venus gradually became a "normal" planet.
These events lead to several key statements that were claimed in the book:
Venus must be still very hot as young planets radiate heat.[3]
Venus must be rich in petroleum gases, and hydrocarbons.[4]
Venus has an abnormal orbit in consequence of the unusual disasters that happened.
Velikovsky suggested some additional ideas that he said derived from these claims, including:
Jupiter emits radio noises.[5]
The magnetosphere of Earth reaches at least up to the moon.
The sun has an electric potential of approximately 10^19 volts.
The rotation of earth can be affected by electromagnetic fields.
Velikovsky arrived at these proposals using a methodology which would today be called comparative mythology - he looked for concordances in myths and written history of unconnected cultures across the world, in particular following a rather literal reading of their accounts of the exploits of planetary deities. In this book, he argues on the basis of ancient cosmological myths from places as disparate as India and China, Greece and Rome, Assyria and Sumer. For example, ancient Greek mythology asserts that the goddess Athena sprang from the head of Zeus. Velikovsky identifies Zeus (whose Roman counterpart was the god Jupiter) with the planet Jupiter. Velikovsky identifies Athena with the planet Venus, although the Greek counterpart of the Roman Venus was Aphrodite and not Athena. This myth, along with others from ancient Egypt, Israel, Mexico, etc. are used to support the claim that "Venus was expelled as a comet and then changed to a planet after contact with a number of members of our solar system" (Velikovsky 1972:182). |
http://ca.answers.yahoo.com/quest...dex.php?qid=20070825094022AAVIpQb
Just a note that Velikovski wrote these claims before there was much scientific information about Venus.
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Baywax
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OK, as long as there's very few people commenting on this idea I have another "out-there" one for Jupiter.
For some reason there's a big rumour and hub-bub going on on the web about Jupiter becoming another sun in our solar system.
Does anyone have scientific data to back this rumour up?
If its a reality... that could also explain the warming taking place not only on Earth but the other planets.
| Quote: | | There are many things the old Greeks did not know about this great light of heaven, but the more we study it the more appropriate it seems that they named it as they did. Jupiter has a diameter about 12 times that of Earth, yet it rotates on its axis more than twice while Earth rotates once. Jupiter has nearly 318 times more mass than Earth: indeed nearly three times more mass than all the other planets combined. Except for the Sun itself, Jupiter is the giant of the Solar System. It is nearly large enough to have become a star. Think about that. If Jupiter had been a bit more massive we would be living in a binary star system. Or would we? If Jupiter had become a star, would life have been possible on Earth? Probably so, for Jupiter would have been a dim star, orbiting 5 times farther out from the Sun than Earth is. For us, its distance constantly changes between 4 and 6 times the solar distance. As Earth sweeps between Jupiter and the Sun it is 4 times farther away than the Sun, and when Jupiter is beyond the Sun, on the far side of its orbit it is 6 times farther from us than the Sun. Thus, if Jupiter had been a star, orbiting just as it currently does, it would be an extremely bright, but constantly changing, light. How different things would be. We would not have had nearly as much darkness, for whenever Jupiter would be in the sky it would cast its much greater brilliance into our otherwise night--far more light than the full moon we know. The famous science fiction author, Arthur C. Clarke, included the idea of Jupiter becoming a star in his series of books, 2001, 2010, 2061, and 3001. |
http://www.clarkfoundation.org/astro-utah/vondel/jupiter.html
and
| Quote: | Warming On Jupiter, Mars, Pluto, Neptune's Moon & Earth Linked to Increased Solar Activity, Scientists Say
IN CASE YOU MISSED IT...
Bright sun, warm Earth. Coincidence?
By Lorne Gunter
National Post
Link to Article
Monday, March 12, 2007
Mars's ice caps are melting, and Jupiter is developing a second giant red spot, an enormous hurricane-like storm.
The existing Great Red Spot is 300 years old and twice the size of Earth. The new storm -- Red Spot Jr. -- is thought to be the result of a sudden warming on our solar system's largest planet. Dr. Imke de Pater of Berkeley University says some parts of Jupiter are now as much as six degrees Celsius warmer than just a few years ago.
Neptune's moon, Triton, studied in 1989 after the unmanned Voyageur probe flew past, seems to have heated up significantly since then. Parts of its frozen nitrogen surface have begun melting and turning to gas, making Triton's atmosphere denser.
Even Pluto has warmed slightly in recent years, if you can call -230C instead of -233C "warmer."
And I swear, I haven't left my SUV idling on any of those planets or moons. Honest, I haven't.
Is there something all these heavenly bodies have in common? Some one thing they all share that could be causing them to warm in unison?
Hmmm, is there some giant, self-luminous ball of burning gas with a mass more than 300,000 times that of Earth and a core temperature of more than 20-million degrees Celsius, that for the past century or more has been unusually active and powerful? Is there something like that around which they all revolve that could be causing this multi-globe warming? Naw! |
http://epw.senate.gov/public/inde...DD8F9-802A-23AD-4459-CC5C23C24651
I know I shouldn't put too much faith in Arthur C. Clarke's predictions and fictions, but, in the least we could say Jupiter does contribute to the general "atmosphere" of our little solar system.!
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