Stories
Slash Boxes
Comments

SoylentNews is people

Submission Preview

Link to Story

Early Asteroids May Have Been Made of Mud Rather Than Rock

Accepted submission by takyon at 2017-07-14 20:11:19
Science

Giant mud balls roamed the early solar system [sciencenews.org]

The earliest asteroids were probably made of mud, not rock. Radioactive heat in the early solar system could have melted globs of dust and ice before they had a chance to turn to rock [sciencemag.org] [open, DOI: 10.1126/sciadv.1602514] [DX [doi.org]], a new simulation published July 14 in Science Advances shows. The results could solve several puzzles about the composition of meteorites found on Earth and may explain why asteroids are different from comets.

[...] Bland reasoned that heat from radioactive decay would melt the ice, and the resulting body would be an enormous dollop of mud. The mud would suspend sediment particles, so they wouldn't be stripped of their sunlike elements. And it would allow the early asteroids to be any size and remain cool.

Bland and Bryan Travis of the Planetary Science Institute, who is based in Los Alamos, N.M., ran computer models of how the mud balls would evolve. Convection currents, like those that move molten rock within the Earth's mantle, would develop, helping to transfer heat into space, the models showed. After several million years, the ball would harden completely, yielding the asteroids seen today.

NASA will make a decision within the next two months on whether to extend the Dawn mission to another asteroid [spacenews.com], leaving Ceres [wikipedia.org].


Original Submission