Researchers determine "rogue" asteroids could actually be perfectly normal.
In the 1980s researchers believed asteroids that were formed near the Sun remained there, and the same for those that formed farther away, a Massachusetts Institute of Technology news release reported.
Over the past decade researchers have spotted asteroids with compositions that do not match up with their location; researchers dubbed these objects "rogue asteroids."
A research team compiled a new map that documented the "composition, and location of more than 100,000 asteroids throughout the solar system," the news release reported. The team found quite a few rogue asteroids and a wide variety of compositions in the asteroid belt between Jupiter and Mars.
The new research suggests early solar system went through dramatic changes; Jupiter may have once been much closer to the Sun with asteroids in tow. When Jupiter migrated it could have knocked these asteroids "outwards."
"It's like Jupiter bowled a strike through the asteroid belt," Francesca DeMeo, a postdoc in MIT's Department of Earth, Atmospheric and Planetary Sciences, said in the news release. "Everything that was there moves, so you have this melting pot of material coming from all over the solar system."
The team made their map using data from the Sloan Digital Sky Survey. The asteroids were grouped by size, location, composition and origins, the news release reported. The survey may have excluded asteroids that are small, dim, and hard to spot. The team determined they were mapping all asteroids that were at least five kilometers (about three miles) in diameter.
The researchers found that when it came to large asteroids warm asteroids seemed to be found in warm regions and vice versa; smaller asteroids tended to go "rogue." Asteroids that were believed to have formed in warm areas of space were found in colder regions.
"The trickle of asteroids discovered in unexpected locations has turned into a river. We now see that all asteroid types exist in every region of the main belt," the team wrote in their paper, the news release reported.
The findings could support the planetary migration theory dubbed the "Grand Tack model." In this theory Jupiter migrated as close to the Sun as Mars now is during the first few million years after the creation of our solar system.
During its migration Jupiter may have crossed through the asteroid belt, which would have caused the objects to "scatter." This contradicts the idea that the solar system's planets have remained intact from the beginning.
"That [theory] has been completely turned on its head," DeMeo said. "Today we think the absolute opposite: Everything's been moved around a lot and the solar system has been very dynamic."
Jupiter's migration could have caused icy asteroids to collide with Earth.
"The story of what the asteroid belt is telling us also relates to how Earth developed water, and how it stayed in this Goldilocks region of habitability today," DeMeo said.
