Jupiter is the Oldest Planet in our Solar System
Posted on June 14, 2017
Scientists have determined that Jupiter is the oldest planet in our solar system. The researchers from the Lawrence Livermore National Laboratory and Institut fur Planetologie at the University of Munster in Germany studied tungsten and molybdenum isotopes on iron meteorites. The isotope analyses of meteorites indicates that Jupiter's solid core formed within only about 1 million years after the start of the solar system history, making it the oldest planet.Thomas Kruijer, lead author of the paper, says in the announcement, "The most plausible mechanism for this efficient separation is the formation of Jupiter, opening a gap in the disc (a plane of gas and dust from stars) and preventing the exchange of material between the two reservoirs. Jupiter is the oldest planets in the solar system, and its solid core formed well before the solar nebula gas dissipated, consistent with the core accretion model for giant planet formation."
Kruijer also says, "We do not have any samples from Jupiter, in contrast to other bodies like the Earth, Mars, the moon and asteroids. In our study, we use isotope signatures of meteorites (which are derived from asteroids) to infer Jupiter's age."
The researchers also say their study indicates that Jupiter's core grew to about 20 Earth masses within 1 million years. This was followed by a more prolonged growth to 50 Earth masses until at least 3-4 million years after the solar system formed. A research paper on the findings was published here in the journal, Proceedings of the National Academy of Sciences.