Could it at one time have been a planet that exploded? Is it just leftover material from when the Solar System formed that never came together to form anything?
2006-10-23 05:20:06 · 13 answers · asked by BOO! 2 in Science & Mathematics ➔ Astronomy & Space
About 4.6 billion years ago, within the dust cloud of the solar nebula, elements with high melting points, such as iron, condensed into dust first, followed by those with lower melting points, like carbon. Closer to the Sun, temperatures remained too high for these materials to condense, and they chemically combined with the higher-temperature elements. In the middle and outer parts of the belt the carbonaceous materials, as well as ice, were able to condense.
After collisions, the dust grains were able to stick together, since they had small relative velocities.
As the planetesimals formed, they were also being heated. Some of the early asteroids formed iron cores. The asteroids in the middle part of the belt underwent lesser degrees of heating. They did not melt, but lost much of their volatile lighter elements and most of their water. Silicate grains and glass were aqueously altered into water-rich claylike particles. The outer belt asteroids may be more primitive bodies, retaining their volatiles.
The main belt is believed to have originally contained an Earth mass or more of material, while the present day belt only contains ~5 × 10-4 Earth masses.
The mass loss is explained by the dynamical depletion of main belt material via gravitational perturbations from planetary embryos and a newly-formed Jupiter that disrupted their orbits, increasing the relative velocity of the planetesimals, so that they began to fragment.
Most of the post-accretion main belt mass may have been taken up by planetary embryos, and while many planetesimals with diameter greater than 200 km disrupted, few of their fragments survived the dynamical depletion event, explaining the limited presence of iron-rich M-types, olivine-rich A-types and non-Vesta V-types today.
2006-10-23 07:15:52 · answer #1 · answered by the_lipsiot 7 · 0⤊ 0⤋
If you add up all the mass in the asteroid belt, you don't even have enough to form a small planet (the total mass is way below Mercury's mass). Even accounting for the loss of some material from the asteroid belt over time (the moons of Mars are likely captured asteroids, for example) there's still not enough stuff there.
Jupiter's gravity (the same resonance that creates the Kirkwood gaps) prevented a planet from accreting there. This scenario is far more likely that a planet exploding. Besides, we know there is plenty of stuff out there that was never part of any planet - the carbonaceous chondrites that occasionally fall to Earth are proof of that.
2006-10-23 12:46:35 · answer #2 · answered by kris 6 · 0⤊ 0⤋
the explosed planet idea dates from the time when astronomers had only very poor estimates of the total mass of the asteroid belt.
Today we know that their total mass is just a little bigger than 130 less than Earth's mass, and that even the Moon's mass is 1.6x more than that of the asteroid belt.
So it seems pretty clear that, at the time the solar system was formed, and gravity waves started resonating and accumulating material, this region at about 2.7 AU (astronominal units, i.e. the average Earth-sun distance), just got unlucky.
Clearly what hurt was the presence of Jupiter. As you know, the sun is not far from 100 percent of the mass of the solar system. And Jupiter is about 3/4ths of what's not the sun...
hope this helps
2006-10-23 12:30:56 · answer #3 · answered by AntoineBachmann 5 · 0⤊ 0⤋
the solar system was such a crazy place when it was born that there where planets colliding into each other, ther where exploding all over the place. the asteroids now are the remains of these such collisions and are held together by the gravitation of the other planets and the sun. sometimes the asteroids collide in the belt and send other asteroids flying out of orbit.
2006-10-23 12:26:15 · answer #4 · answered by joey h 3 · 0⤊ 0⤋
I think it was once a huge planet like neptune and got hit by an enormous asteroid or comet. Thats mayb why there are SO many fragments of it left that they form one huge belt arond the solar system. If u add all those asteroids into one they will definetly form one huge planet.
2006-10-23 12:23:09 · answer #5 · answered by Anonymous · 0⤊ 1⤋
Dust that happened to be in the wrong place at the wrong time. Provided with movement by the nebula collapse but, too far away from the center and too dispersed to be compressed into a significant gravity required to form a planet.
2006-10-23 18:31:14 · answer #6 · answered by Anonymous · 0⤊ 0⤋
The gravitational field of Jupiter means that at that distance from the sun, no large body can form. The perturbations from Jupiter ensure that.
There are gaps in the belt, known as Kirkwood gaps, which are caused by resonances with Jupiter.
2006-10-23 12:27:21 · answer #7 · answered by Morgy 4 · 0⤊ 0⤋
Nothing but that. Due to the gravitional influence of Jupiter, this pieces of debris couldn´t form into a planet
2006-10-23 12:28:50 · answer #8 · answered by Dark_Luigi 2 · 0⤊ 0⤋
I don't understand how it could have been a planet or other object that broke apart. I don't see what could have happened to it to overcome gravity. I go with the leftover pieces theory.
2006-10-23 12:23:51 · answer #9 · answered by Anonymous · 0⤊ 0⤋
Most likely, it is just leftover debris. Some pieces are larger due to accretion, but I haven't heard the 'explosed planet' idea before.
2006-10-23 12:21:59 · answer #10 · answered by eri 7 · 0⤊ 0⤋