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Astrophysicists have announced an exciting, new view of the early Solar System.


Click the image to see the Discovery.com story on one asteroid's water plume.
In the solar system's infancy, after the planets, asteroids and smaller bodies had formed, we didn't see gentle, circular(-ish) orbits as we do today for most major bodies. Since the 1980s, astronomers thought the Asteroid Belt formed where it lives today, a loose formation between Mars and Jupiter, a loose scattering of rock and dust that simply failed to form into a planet. However, astronomers have been studied a lot of asteroids since that time, some close-up using robotic missions like NEAR-Shoemaker. We have now learned that things weren't always as they are now, and that violence and randomness ruled the early Solar System.



"What we're leaning toward now is that asteroids, rather than forming in the asteroid belt, formed throughout the entire solar system... as close to the Sun as Mercury and as far away as Neptune, and then, through the planetary migration, you scatter them all over the place. What's left is what you see in the asteroid belt today," says astrophysicist Francesca DeMeo. The new theory is that the asteroids now residing in their Mars-to-Jupiter prison had once flown free throughout the Solar System, free to pummel planets, hurtle to a fiery death in the Sun, careen off into deep space on their own. Wildly orbiting planets launched these smaller bodies hither and yon. How crazy were these early planetary dances? It now appears that Mars might have visited Earth's realm - which also explains why we regularly find Mars meteorites on Earth - and mighty Jupiter's orbit once dipped as close as Mars' current locale. All this random chaos meant that little guys like comets and asteroids had no say in where they lived, and the Big Guys like Jupiter really were the gods who controlled the lives of billions of little guys populating the Solar System. The Old Gods might even be responsible for life on Earth, seeding our planet with water by hurtling comets and other icy bodies at us, plus carbon compounds from carbonaceous asteroids. I can see the headline: "Science Proves Life Came from the Gods!"

Click this thumbnail to see the full-size asteroid infographic.


Sure, now Lord Jupiter is happy to maintain a stately, near-circular orbit, maintaining a gravitational fence around the wild ones penned in the Asteroid Belt (Lord Mars keeps the other gate shut), but in their youth they were unpredictable gods, much like their namesakes.

Had to share this little bit of Astro-Awesomeness. I'll leave you with this lovely image of dwarf-planet Ceres (formerly known as "asteroid Ceres," but now a peer of Lord Pluto):


Click the image to see the Wikipedia article on Ceres.

PS: It now appears that Ceres - which makes up about 1/3 of all the asteroid-ish mass in the Solar System - is habitable; that is, is giving off a plume of water vapor. This place has a water-rich atmosphere!

These discoveries... I tell you what: We live in amazing times.

Chris

Comments

( 10 comments — Leave a comment )
jonathan fries
Jan. 31st, 2014 04:19 am (UTC)
Question
That's awesome! Do you have any information on why things settled down?
mckitterick
Jan. 31st, 2014 05:38 am (UTC)
Re: Question
I expect it's because things reached stable orbits over time; it takes a lot of energy to swing wildly this way and that, and sapping that energy drives a body toward the calmest orbit. It's a form of entropy: Things tend toward averages, and all the other bodies (including the Big Guy, Sol) strive toward equilibrium. All those crazy objects that retain greatly elongated orbits? Tend to either crash into the Sun or something else over time.
the_lucky_nun
Jan. 31st, 2014 04:04 pm (UTC)
Yay! I like space posts!
mckitterick
Jan. 31st, 2014 09:47 pm (UTC)
My job is done *g*
carmy_w
Jan. 31st, 2014 09:46 pm (UTC)
Cool post!

Do you think they'll have colonies on other planets in our lifetime? I'm still hoping so....
mckitterick
Jan. 31st, 2014 09:51 pm (UTC)
Well...
carmy_w
Jan. 31st, 2014 10:00 pm (UTC)
Re: Well...
Hmmmm.
Well, I'll adopt a wait and see attitude with that one...

(I immediately thought of "The Moon is a Harsh Mistress")
mckitterick
Jan. 31st, 2014 10:16 pm (UTC)
Re: Well...
I hear you!

But if China says it's going to do something, they're a lot more likely to pull it off than a democracy....
carmy_w
Jan. 31st, 2014 10:20 pm (UTC)
Re: Well...
You do have a point. I dislike it intensely, but you do have a point.
mckitterick
Jan. 31st, 2014 11:32 pm (UTC)
Re: Well...
Ooops! Sorry, here it is:

Though this might have a chilling effect on their plans....

Edited at 2014-01-31 11:32 pm (UTC)
( 10 comments — Leave a comment )