October 2, 2022

Jupiter formed much farther from the Sun. Researchers have determined the origin of the gas giant

The largest planet in the Solar System – Jupiter – was formed four times farther from the Sun than its current orbit, according to a study by Swedish scientists. The gas giant for 700,000. years it migrated inward into the system. Lund researchers claim to have found evidence of this.

The size and location of Jupiter in our solar system has baffled researchers for years, because it doesn’t fit our understanding of the formation of planets. It seems that gas giants cannot form so close to a star. Intense gravity, radiation (including heat) and strong stellar winds would have prevented the gases from staying together long enough to form a planet.

Now astronomers at Sweden’s Lund University say they have found evidence of a long sub-routeóThat Jupiter moved from the outer fringes of our planetary system to its present position. The findings have been accepted for publication in the journal „Astronomy & Astrophysics”. They can now be consulted at the preprint siteóin the arXiv.

Gas giants in other planetary systems orbit very close to their parent stars. According to the prevailing theory, these giant planets formed in the outer regions of the system and then migrated to an orbit closer to the star. Researchers using advanced computer simulations worked out the route thatórą traveled by Jupiter through our solar system about 4.5 billion years ago.

At the time, Jupiter, like the rest of the planets in the Solar System, was a very young planet. Planets gradually gained mass through cosmic dust, whichóry orbited wokół of our young sun in the gas-dust disk. Jupiter inóAt that time it was not much larger than Earth.

According to computer simulations, the gas giant formed near the orbit of Uranus, which is four times farther than its current position. For the next 700,000. years was slowly making its way into the inner Solar System.

– For the first time we have evidenceód to the fact that Jupiter formed far from the Sun and then migrated to its current orbit, said Simona Pirani of Lund University, head of theówna author of the study. – We found evidence of migration in Trojan asteroids orbiting near Jupiter – added.

The Trojans, as the Trojan asteroids are sometimes referred to, are two groups of thousands of asteroids thatóre located at the same distance from the Sun as Jupiter, but orbiting in front of and behind Jupiter, respectively. There are about 50 percent more Trojan asteroids in front of Jupiter than behind it. It is this asymmetry that has become key to scientists’ understanding of theóIn the history of Jupiter’s migration.

– This asymmetry has always been a mystery in the Solar System – acknowledged Anders Johansen, professor of astronomy at Lund University. In fact, the research community has not been able to explain why the two groups of asteroids do not contain a similar number of space rocks. Scientists used computer simulations to figure out what could have caused such a strange nierównowaga.

Researchers have reconstructed the course of events during Jupiter’s formation process and howób how the planet gradually attracted Trojan asteroids. They calculated that the current asymmetry could only exist in a scenario where Jupiter formed four times farther from the Sun and then migrated to its current position. During the journeyóJupiter’s living gravity attracted more Trojansóin front of it than behind it.

According to calculations, Jupiter’s migration lasted about 700,000 years. This took place between 2 and 3 millionóin the years after Jupiter began its life as an icy asteroid orbiting far from the Sun. Podrótended to follow a spiral and a tighter and tighter path into the solar system. The reason for the migration was the gravitational interactions of the planet with the surrounding gas filling our planetary system.

Simulations show that the Trojan asteroids were attracted to Jupiter when it was a young planet without a gaseous atmosphere, meaning that these asteroids most likely consist of matter similar to that whichóra make up the core of Jupiter.

In 2021, the Lucy space probe will be launched, która will enter orbit wokół six Trojan asteroids to study them in detail.

The authors of the study suggest róalso that Saturn and the ice giants Uranus and Neptune may have migrated in a similar wayób.