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Jupiter Destroyed 'Super-Earths' In Our Early Solar System
sciencehabit writes: If Jupiter and Saturn hadn't formed where they did—and at the sizes they did—as the disk of dust and gas around our sun coalesced, then our solar system would be a very different and possibly more hostile place, new research suggests (abstract). Computer models reveal that in the solar system's first 3 million years or so, gravitational interactions with Jupiter, Saturn, and the gas in the protoplanetary disk would have driven super-Earth–sized planets closer to the sun and into increasingly elliptical orbits. In such paths, a cascade of collisions would have blasted any orbs present there into ever smaller bits, which in turn would have been slowed by the interplanetary equivalent of atmospheric drag and eventually plunged into the sun. As Jupiter retreated from its closest approach to the sun, it left behind the mostly rocky remnants that later coalesced into our solar system's inner planets, including Earth.
Because it's a big-ass sky with lots of solar systems.
No, seriously. We used to think planets around stars would be rare. Now we know otherwise.
Think of it like a lava lamp ... it happens according to knowable rules. But it doesn't happen the same way every time.
What we keep seeing is a stunning diversity in how individual solar systems form. Not some uniform composition.
I'm no astronomer, but this is more about there simply being a huge amount of possible combinations, in a vast collection of instances.
Lost at C:>. Found at C.
So how come that happened in our solar system, but not in the many other exo-planetary systems that we have found recently/
Selection bias. Our planet detection technology is still very primitive. We have found lots of big, hot planets orbiting very close to stars, not because they are common, but because they are easy to detect.
Jupiter and Saturn shall be sentenced to death for deviating from the approved Stellar System Standards, which has resulted in the formation of humans and other pestilences.
Table-ized A.I.
God does play dice with the universe.
Or at least, marbles.
Faster! Faster! Faster would be better!
God does play dice with the universe.
Or at least, marbles.
"God does not play dice with the universe; He plays an ineffable game of His own devising, which might be compared, from the perspective of any of the other players(everyone else), to being involved in an obscure and complex version of poker in a pitch-dark room, with blank cards, for infinite stakes, with a Dealer who won't tell you the rules, and who smiles all the time" ---Terry Pratchett.
---Saying gnome 3 is better than windows 8 not so much a compliment as it is damning with light praise.
So, we're looking for other civilizations, haven't found any, even though we estimate that life should be common. After all, if it happened here it should be able to happen in a lot more places.
But perhaps the set of circumstances that would create an environment that lasted long enough for life to be created and evolve to this point are wildly, vanishingly improbable. Perhaps the only reason we think it should have happened lots of other places is that we are the ones doing the looking, and we don't realize just how rare we actually are.
But that's a little depressing.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
Easier to Detect. The easiest to detect is great big gas giants nearly the size of their star orbiting very closely (hot gas giants). Those were the first discovered and comprise the majority of systems discovered so far because the bigger the planet and the closer to the star the easier it is to infer with the current detection techniques. We've never actually imaged one of these worlds, we've only inferred their presence for example by rhythmic flickering from a planet passing in front of the star.
As someone (I can't recall who) said, trying to find planets is like trying to see a mosquito in front of a 10,000 watt light bulb from a football field away. In other words is pretty difficult, in fact so difficult we can only find planets through inferred methods, not direct imaging. Unless we can find a way to completely block all the light from the star without blocking anything illuminated by the star and thousands of times more magnification (say a focal length of half the solar system) we aren't going to image a planet like earth. Space is really really big and the distance between stars so great that even when two galaxies collide there is very little chance of two stars impacting.
No. The theoretical lower limit on a star's mass in 13 Jupiter masses. source
- Isaac Asimov.
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