Posted on 03/25/2002 2:42:10 PM PST by vannrox
Asteroid Vesta: The 10th Planet? Discovery Brightens Odds of Finding Another Pluto Nemesis: The Million Dollar Question HOUSTON, TEXAS -- Our solar system may have had a fifth terrestrial planet, one that was swallowed up by the Sun. But before it was destroyed, the now missing-in-action world made a mess of things. The temporary existence of more than 4 planet-sized bodies in the inner Solar System is consistent with the currently favored model for the formation of the Moon. Work by Chambers and Lissauer also supports the view that our Moon is a leftover of a massive collision between Earth and a Mars-sized body 50 million to 100 million years after the formation of the Solar System. Wendell Mendell, a planetary scientist here at NASA's Johnson Space Center, said the new theory is intriguing. "By thinking that the Solar System was really quite different in a major way with an extra inner planet, we might be able to develop some sort of self-consistent scenario that explains a lot of things. But all this is at the very early stages now," Mendell said. "You're going to have to be very, very specific on what sites you go to collect new samples," Schmitt told SPACE.com. "It may be very difficult to get an answer without using missions to fairly large impact craters that penetrate through the ejecta. Those impacts are sort of a drill hole into the lunar crust," he said.
Space scientists John Chambers and Jack Lissauer of NASA's Ames Research Center hypothesize that along with Mercury, Venus, Earth, and Mars -- the terrestrial, rocky planets -- there was a fifth terrestrial world, likely just outside of Mars's orbit and before the inner asteroid belt.
Moreover, Planet V was a troublemaker.
The computer modeling findings of Chambers and Lissauer were presented during the 33rd Lunar and Planetary Science Conference, held here March 11-15, and sponsored by NASA and the Lunar and Planetary Institute.
It is commonly believed that during the formative years of our solar system, between 3.8 billion and 4 billion years ago, the Moon and Earth took a pounding from space debris. However, there is an on-going debate as to whether or not the bruising impacts tailed off 3.8 billion year ago or if there was a sudden increase - a "spike" -- in the impact rate around 3.9 billion years ago, with quiet periods before and afterwards?
This epoch of time is tagged as the "lunar cataclysm" - also a wakeup call on the cosmological clock when the first evidence of life is believed to have appeared on Earth.
The great cover-up
Having a swarm of objects clobbering the Moon in a narrow point of time would have resurfaced most of our celestial next door neighbor, covering up its early history. Being that the Moon is so small, Earth would have been on the receiving end of any destructive deluge too.
Moon-walking astronauts brought back a cache of lunar material. Later analysis showed that virtually all impact rocks in the "Apollo collection" sported nearly the same age, 3.9 billion years, and none were older. But some scientists claim that these samples were "biased", as they came from a small area of the Moon, and are the result of a localized pummeling, not some lunar big bang.
There is a problem in having a "spike" in the lunar cratering rate.
That scenario is tough to devise. Things should have been settling down, according to solar system creation experts. Having chunks of stuff come zipping along some hundreds of millions of years later out of nowhere and create a lunar late heavy bombardment is a puzzler.
If real, what were these bodies, and where were they before they scuffed up the Moon big time? The answer, according to Chambers and Lissauer, might be tied to the the Planet V hypothesis.
"The extra planet formed on a low-eccentricity orbit that was long-lived, but unstable," Chambers reported. About 3.9 billion years ago, Planet V was perturbed by gravitational interactions with the other inner planets. It was tossed onto a highly eccentric orbit that crossed the inner asteroid belt, a reservoir of material much larger than it is today.
Planet V's close encounters with the inner belt of asteroids stirred up a large fraction of those bodies, scattering them about. The perturbed asteroids evolved into Mars crossing orbits, and temporarily enhanced the population of bodies on Earth-crossing orbits, and also increased the lunar impact rate.
After doing its destabilizing deeds, Planet V was lost too, most likely spinning into the Sun, the NASA team reported.
Striking view
"This idea and others within the last few years show that the Solar System is filled with all sorts of gravitational resonances...that a lot of potential orbits in the Solar System are chaotic and unstable," Mendell told SPACE.com. "My sense is that this is a new idea. It's another thing to throw into the pot that's not totally crazy."
The work suggests there's a match up in timing, Mendell said, with asteroids striking the Moon and causing the effects that are seen in the dating of Apollo lunar rocks.
"We're moving into a really new regime," Mendell added, "where the Solar System is not a static dynamic place from day one to now. It really might have had some nuances and synchronicities associated with it that we have not really tried to exploit before."
It takes a drill hole Setting the early Solar System and lunar history record straight means going back to the Moon.
"The Moon is still the keystone to our understanding of the Solar System," NASA's Mendell said.
That too is the view of Apollo 17 astronaut, Harrison "Jack" Schmitt. Getting back to the Moon to sort out the real story is a must, he said.
Dating service
Places on the Moon where older, large basins have deposited ejecta are ideal research zones, Schmitt said. Digging into such sites could yield impact glass formed by basins perhaps dating older than 3.9 billion years old, he said.
Just taking spot samples -- say from the Moon's South Pole Aitken basin -- could be risky, in terms of uncovering the Moon's rocky history, Schmitt said. Such a huge area would take multiple robotic or human exploration missions, each with significant roving abilities.
Also known as the "Big Backside Basin," Aitken is the largest impact crater on the Moon, and one of the biggest in the Solar System.
For the near term, sets of low-cost, mini-robotic landers carrying specialized gear would be ideal in opening up the Moon to further exploration, Schmitt said.
"Numbers of targeted missions could get a lot of great information on some of these fundamental questions that we still haven't been able to answer," Schmitt said.
Getting back to the Moon with a settlement for resource exploitation is another step forward. From such a site, human explorers can survey various lunar locales - even the Moon's side that we Earthlings never see, Schmitt said. "Then we can do the kind of thing that Apollo did for the near side of the Moon," he said.
This is talking about stuff billions of years ago.
Most of the early Speculation involved a "Near Miss" of Jupiter, resulting in the "Tidal Forces" of intense gravitation ripping the "Planet" apart--Thus the "Asteroid Belt..."
But there's also the "Velikovsky Model," in which the Planet Venus is the "Stray Astronomical Body" responsible for both the Moon & MANY Other Phenomena in the Skies!
One MINOR point----Velikovsky DID predict "surface Conditions & Chemistry" on Venus FAR More Accurately than "Astronomers" of his time! (surface Temperatures ~ 700+degrees; Chemistry Mostly Hydrocarbons!)
But--of Course--Velikovski was a "Von Daniken-Level" "Whack-Job!!"
Only goes to show the depth of our Ignorance!
Doc
You are a kind and generous soul.
However, back in August, Alec Baldwin said that if Bush's approval rating ever rose above 60%, he would colonize the moon. He has alreaddy renigged on his promise, stating that ex-wife was quoted out of context and was punch drunk at the time anyway.
The planet Vulcan is supposed to be in the same orbit as Earth, just directly opposite the sun, and thus perpetually invisible to us from Earth. Well, that's the so-called theory, or notion, at any rate! ;-)
Your math is backwards. Slowing the rotation of the Earth will present fewer days of longer duration. Try 243 36-hour days per year or some other convenient variant that totals 8760 hours per year.
The structure of a planet could cause it to explode as it cooled. Kind of like an implosion.
As you pointed out, in the early 50's he predicted that Venus would be much hotter (specifying the temperature that would be found within 35 degrees) than can be accounted for by "greenhouse" effect at a time when "astronomers" and "planetologists" were confident that Venus was covered by water oceans and temperatures only 50 deg. F. above Earth's, accurately described the chemical makeup of the atmosphere of Venus that was later corraborated by probes when most astronomers and planetologists were convinced that Carbon Dioxide (actually almost non-existent) would be the primary component, and that they would find some strange things about the actual rotation of the planet... and we find that not only is Venus revolving retrograde, it is apparently tidally locked on Earth!
More and more archealogical anomolies are being found that calls our current orthodox chronology into question.
It seems to me that the test of any theory is how well does it predict actual events. Using this as a criteria, Velekovsky seems to doing all right.
Thanks for the answer. That leads to another question. C14 works because something alive "eats" the carbon, and when it dies, no more carbon is collected in it. By measuring the C14, and knowing the half-life, a good guess to the age the thing died can be determined.
What is the process that causes rocks to collect whatever is being used (potassium?), then stop collecting it so the age can be determined? Wouldn't all rocks show the age they were formed? Or could they be formed out of older rocks, and show that age? And if a planet exploded and showered rocks on the moon, would the age be when they were formed or when they showered? Couldn't they shower down at different times, yet show the same age?
I'm sure it is something simple that I am missing, here, isn't it?
I like the answer. Guess I was asking for that.
I'll try again. How does one determine the age of a rock? And counting the rings won't quite work here.
Maybe counting the candles on the cake?
Well finally, after so many centuries dominated by Archimedes, Ptolemy, Galileo, Kepler and many others, the truth comes out.
A CommiePinkoLeftistcentric Cosmology. Will wonders never cease?
;^)
Sire, je n'avais pas besoin de cette hypothese.
When Newton presented his work on Celestial Mechanics, he stopped short of a complete work--treating the planets and the Sun as a series of individual two-body problems. At the time, he is said to have remarked concerning the remaining and unaccounted for perturbations in the orbits of the planets: "The rest is in the hands of the Creator."
Laplace, the great mathematician, set himself the ambitious task of refining and perfecting Newton's calculations involving mechanics in a book that should offer a complete solution of the great mechanical problem presented by the solar system. The result was the highly acclaimed five volume set, Mecanique Celeste. In it he shows that the (current) solar system is stable and self-regulating.
When Laplace presented the first edition of his work to Napoleon--so the story goes--Napoleon alluded to Newton and remarked, "Monsieur Laplace, they tell me you have written this large book on the system of the universe, and have never even mentioned its Creator." To this Laplace replied bluntly, "Sire, I had no need for that hypothesis."
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