The theory of planet formation that scientists have been talking about for decades appears to be jeopardized by a recent study of old meteorites. The theory explains how rocky planets like Earth and Mars acquire volatile elements such as hydrogen, carbon, oxygen, nitrogen and noble gases during their formation stages. During the study, scientists observed trace amounts of krypton isotopes in meteorite samples. The low abundance of krypton isotopes makes it more difficult to measure. So, to find out where these isotopes came from, the researchers used a new method established at the UC Davis Noble Gas Laboratory.
According to Sandrine Péron, a postdoctoral scholar working with Professor Sujoy Mukhopadhyay in the UC Davis Department of Earth and Planetary Sciences, “A fundamental assumption about planet formation is that planets first collect these volatiles from nebulae around young stars.” Recent research contradicts this process.
Scientists have found that krypton isotopes in meteorites suggest they came from meteorites, not from the solar nebula. This suggests that even in the presence of the solar nebula, meteorites were delivering volatile elements to the planet at an earlier stage of formation, contradicting previous beliefs.
New research suggests that Mars’ growth was completed before solar radiation dissipated the nebula. But radiation should also blow away the nebula atmosphere on Mars. This means that atmospheric krypton must be preserved somehow, either trapped underground or stored in polar ice caps.
Professor Mukhopadhyay said: “However, this required Mars to cool immediately after accretion. While our study clearly points to a chondrule-like gas inside Mars, it also raises some interesting questions about the origin and composition of Mars’ early atmosphere. .”
Krypton, like other noble gases, helps discover the source of volatile substances on planets.