Jupiter is the largest known planet in our Solar System today, and astronomers have a lot of questions about it, but one new clue discovered by researchers from Brown University might be able to put a somewhat accurate timescale on the planet thanks to a specific kind of meteorite that lingers in the solar system today.
According to the research, which appears in Science Advances this month, Jupiter may have existed in its current full-sized form just as much as 5 million years after the first solids came into existence in our Solar System.
They deduced this theory by examining special kinds of meteorites called CB chondrites, which are believed to be meteorites formed out of materials from our early Solar System.
According to the research, these meteorites were formed when objects, most likely from the Solar System’s asteroid belt, slammed into each other at great velocities, which would have been great enough to vaporize iron.
As the research indicated, the only way for iron to vaporize is for the matter to have impacted similar matter in space at incredibly fast speeds – at least 20 kilometers per hour and only going up from there. Unfortunately, current data models suggest these meteorites would have only been going around 12 kilometers per hour, so something didn’t add up.
The researchers believe that Jupiter played a significant role in creating these early-Solar System meteorites, which places Jupiter in all of its current glory in the early Solar System. Its massive planetary size would have been required to generate the gravitational forces necessary for making these high-velocity impacts.
"We show that Jupiter would have stirred up the asteroid belt enough to produce the high-impact velocities necessary to form these CB chondrites," said Brandon Johnson, a planetary scientist at Brown University who led the research. "These meteorites represent the first time the solar system felt the awesome power of Jupiter."
For this to happen, Jupiter would have existed closer to the position of the asteroid belt at some point in time, but the formation of Saturn and the other larger gassy planets would have added a gravitational pull that eventually tugged Jupiter out to where it is today. This seemed to suggest Jupiter formed in the outer parts of the Solar System and migrated inward from the Sun’s gravity before being tugged back out to where it exists today. This idea is called the Grand Track.
"When we include the Grand Tack in our model at the time the CB chondrites formed, we get a huge spike in impact velocities in the asteroid belt," said Kevin Walsh of the Southwest Research Institute in Boulder. "The speeds generated in our models are easily fast enough to explain the vaporized iron in CB chondrites."
The moral to the story is that because of the conditions that were required to form these kinds of meteorites, scientists believe that Jupiter played an important role in generating the velocities required to create the CB chondrites. Without Jupiter, none of the researchers’ models seem to make any sense, so that would place Jupiter (and its powerful gravitational pull) in the early Solar System.
Source: Brown Unviersity