Posted on 11/11/2011 5:16:23 AM PST by decimon
The ‘Great Gesundheit’.
Gas giants credited for solar system formationJupiter and Saturn form the basis of a "grand unified theory" of the solar system, according to new computer simulations. The research traces three seemingly unrelated phenomena -- the giant planets' orbits, craters on the Moon, and the behaviour of certain asteroids -- to the motions of the two gas giants nearly four billion years ago... an international team of researchers has performed computer simulations that reproduce the orbits of the four giant planets -- Jupiter, Saturn, Uranus, and Neptune -- in exquisite detail. The team has published a trio of papers about their findings in Nature. In the model, the four planets form in 10 million years within the current orbit of Uranus. Surrounding them in a ring are several thousand rocky objects called planetesimals, left over from the formation of the planets... planetesimals begin to "leak" into the giant planet zone and the orbits of the giant planets gradually change. After 700 million years, Saturn has migrated outward and Jupiter inward to the extent that they reach a "resonance" point. This means they begin to march in lockstep with each other, with Jupiter completing two orbits around the Sun for every one of Saturn's. The resonance allows the pair to greatly disturb the orbits of the other planets.
by Maggie McKee
25 May 2005Did Jupiter Bully Other Planets in Sibling Rivalry?One possible explanation, discussed in Thursday's issue of the journal Nature, is that Uranus and Neptune formed much closer to the center of the action than their current positions might indicate. In this scheme, Jupiter and Saturn were bullies of a protoplanetary playground, shoving the other two future giants out of the way.
by Robert Roy Britt
8 December 1999Jupiter gave birth to Uranus and NeptuneNot too long ago, scientists regarded the orbits that the planets circle our Sun as being the ones they were born in. Now they are realising that this is not the case. Uranus and Neptune may have migrated outwards and Jupiter may have come in from the outer cold. Scientists have always been slightly puzzled by the positions of Uranus and Neptune because in their present locations it would have taken longer than the age of the Solar System for them to form. Scientists from Queen's University suggest that the four giant planets started out as rocky cores in the Jupiter-Saturn region, and that the cores of Uranus and Neptune were tossed out by Jupiter's and Saturn's gravity.
by Dr David Whitehouse
8 December, 1999Jupiter's Composition Throws Planet-formation Theories into DisarrayExamining four-year-old data, researchers have found significantly elevated levels of argon, krypton and xenon in Jupiter's atmosphere that may force a rethinking of theories about how the planet, and possibly the entire solar system, formed. Prevailing theories of planetary formation hold that the sun gathered itself together in the center of a pancake-shaped disk of gas and dust, then the planets begin to take shape by cleaning up the leftovers. In Jupiter's current orbit, 5 astronomical units from the sun, temperatures are too warm for the planetesimals to have trapped the noble gases. Only in the Kuiper belt -- a frigid region of the solar system more than 40 AU from the sun -- could planetesimals have trapped argon, krypton and xenon.
by Robert Roy Britt
Nov 17 1999
While lead researcher Tobias Owen does not put much stock in the idea that Jupiter might have migrated inward to its present position, other scientists on the team say the idea merits consideration. Owen expects the probes will find similarly high levels of noble gases in Saturn, Uranus and Neptune. Hints of these gases have even been found in the thick atmosphere of Venus, another planet now begging more study.Have Jupiter's smallest moons been obliterated?The Long Range Reconnaissance Imager (LORRI) camera on New Horizons should have been able to spot moons down to a diameter of about 1 kilometre. But it saw nothing smaller than Adrastea, a 16-kilometre-wide resident of Jupiter's faint ring system (see image at right). This is puzzling, because scientists expected the number of objects to increase at smaller size scales, as they do in the rings of Saturn. The missing moons may have been eroded away by micrometeoroids, say researchers led by Mark Showalter of the SETI Institute in Mountainview, California, US. A steady rain of small objects -- probably between the sizes of a grain of sand and a pebble -- would destroy small moons while leaving larger ones mostly intact, they say. For example, a 27-kilometre-wide moon could survive having its outer 5 km worn away over time, whereas an object just 5 km across would be eroded away to nothing in the same time period... But why did this process spare Saturn's small moons? Showalter thinks the answer has to do with the fact that Saturn is simply less massive than Jupiter.
by David Shiga
New Scientist
October 9, 2007
...the solar system may have given up a giant planet and spared the Earth, according to an article recently published in The Astrophysical Journal Letters.Deus ex machina. I'm getting a "Connection Refused!" error, must be very busy on FR, or there's a cyberattack going on.
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Rogue Planet Find Makes Astronomers Ponder TheoryEighteen rogue planets that seem to have broken all the rules about being born from a central, controlling sun may force a rethink about how planets form, astronomers said on Thursday... "The formation of young, free-floating, planetary-mass objects like these is difficult to explain by our current models of how planets form," Zapatero-Osorio said... They are not linked to one another in an orbit, but do move together as a cluster, she said... Many stars in our own galaxy, the Milky Way, may have formed in a similar manner to the Orion stars, she said. So there could be similar, hard-to-see planets floating around free near the Solar System.
by Maggie Fox
October 5, 2000
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Is this the one that is causing perturbances in the Oort Cloud?
Nope, it’s out, gone, sayonara. “Fossil” disturbances might remain though, assuming that the Oort Cloud exists.
What ever happened to the conjecture that the asteroid belt was caused from the disintegration of a planet between Mars and Jupiter? Also, how big would such a planet have been? Might it have been damaged when the 5th giant planet was ejected, or could it have been that 5th planet?
I think there was a recent post by SC about complex organic molecules being found in space. I just checked the book Comet by Carl Sagan and Ann Druyan. There are a number of pages speculating on the origin of life on earth. Basic components may have been produced on earth, or may have been introduced by comets and even asteroids, or a combination of causes. Also interplanetary dust from comets falls on earth. Components found in comets include simple hydrocarbons, methane, ethane, methyl alcohol, hydrogen cyanide, and formaldehyde. Comets made a major contribution of water to our earth as well.
I am not clear what you mean by cross species evolution, but the book “The Ancestor’s Tale” lays out the divergence of new life forms in a very understandable, sequential manner, going all the way back to the most primative preCambrian single cell organisms. Incidentally, the first cells had no nucleus, then a nucleus but no mitochondria, and finally a cell with mitochonria. Then the cells needed to “learn” to stick together and form more complex life.
I agree. This is why the Big Bang and abiogenesis require much more faith than belief in the God of the Bible. Both are religious beliefs, and neither can be proven conclusively. We each must weigh the evidence and place our faith in what it most worthy, in our estimation.
It is practically impossible to prove anything in physics 100% conclusively. But there are theories of varying certainty based on quantifiable observations and experiments.
For example, there is a good deal of observable evidence of a “Big Bang”. Direction, velocity, and acceleration of galaxies can be determined. It paints a picture of a high energy event originating from one point with the relative intensity of an explosion. What exactly was that event and what caused it? We may never know since it was way before our time.
There is also observable evidence that the universe is like an energy pendulum, eventually imploding into a single black hole or many black holes. At each galaxy, there is a giant super black hole at the center. Perhaps there is a critical point where the energy absorbed by the black hole is once again released as mass to implode and create yet another universe. That can only be studied on paper for now.
But as far as an intelligent, deliberate Deity goes? We don't have a single piece of observable evidence or any experiments that show this possibility. It's not that most people in the scientific community don't want to admit God exists. There just has to be at least something tangible to point in that direction. A book written by man with no extraterrestrial qualities is not scientific evidence. Perhaps such a book did exist but there is nothing tangible that says it ever did.
Well, FWIW, the scriptures explain that God “stretched out” the heavens, and that he created the earth before the sun moon and stars. Scripture also explains that the creation is “wearing out like a garment”, which God will roll up like a scroll. Written over 2000 years ago, well before the telescope and Doppler theory were developed. This is also a reasonable explanation for the observations we make today. No human was present at creation to observe it, and we tend to dismiss eyewitness testimony anyway, so any explanation of origins is conjecture, requiring faith on the part of the adherents. Want proof of God? Honestly consider the claims of Jesus, and the proofs of his resurrection. If he rose...
Pardon if this is a duplicative answer, I opened this in a tab some hours ago, and am now back home. :’)
The amount of mass *currently* in the main asteroid belt is insufficient to produce a planet if it were piled up in one pile. Without checking, I think Ceres (the largest of the main belt asteroids, and first one discovered) has more than half the entire mass, analogous to the way Jupiter has more mass than all the rest of the (known) planets combined.
The rubble of a planet that went kablooey could be expected to head off in eccentric paths, and to be gradually absorbed by other surviving bodies, such as Jupiter. The main issue for the late Thomas Van Flandern was, what mechanism caused his hypothetical planet (and eventually, planets) to explode?
Anyway, here’s an overview from TVF’s website, mentions Olbers who, in 1802, suggested that very origin for the main asteroid belt:
http://www.metaresearch.org/solar%20system/eph/eph2000.asp
The Nine Planets — Asteroid facts, pictures and information
http://nineplanets.org/asteroids.html
“The total mass of all the asteroids is less than that of the Moon.”
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