I was watching a documentary earlier tonight about why astronomers think that unlike many solar systems documented, ours has no super-earth. In the theories they have, in the early solar system, the inner solar system was populated by many large rocky planets. Eventually their orbits crossed paths, the collided with one another and at the same time Jupiter was migrating towards the inner solar system. A lot of rocky material plunged into the sun, the large rocky worlds that survived plunged into the sun and once Saturn developed, it pulled Jupiter back out into the solar system, leaving very little material behind in the inner solar system to rebuild the rocky planets.

What we have now are small, rocky (2nd generation) planets and it kind of reminds me of the situation we all have now. Yes it was only one huge group that was shattered, but the situation is similar. Now let's make sure that we don't wind up like Mercury and be the smallest of them! Share us with your friends and let's get rolling!

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I like Mercury. I like how it is full of metal.

6558547

Well early on in its history it is theorized that it was hit by a large object, a good part of its crust was blown off into space and what was left behind was primarily its iron core. It wasn't always as small as it is.

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I heard it might have ice at the bottom of the craters. Near the poles.

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After sending a probe to Mercury, astronomers have reason to believe that there is water ice deep in craters at the poles, places where the sun never shines. Even ten years ago had someone brought up the idea of ice on Mercury, they would have been laughed at.

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It makes sense if you think about it. Mercury has very little atmosphere. Nothing to retain the heat from the sun. Since the sun's rays can't reach the deep part of these craters. There is a good chance of ice. It is also interesting to note. That nights on Mercury are extremely cold.

Yep, they are cold, -300 degrees. There also a lot of extra-solar planets that have been discovered, ones that are believed to be tidally locked to their star without atmospheres. Those are closer to their star than Mercury and it is believed the dark sides of those are frozen wastelands. I tell you, some of the things that are either science fact or very likely to be true theories are stranger than anything science fiction could throw our way.