California Institute of Technology | 2019 Sep 04
Researchers present a new paradigm for understanding how pressures in planets evolve
A new study from Caltech shows that giant impacts can dramatically lower the internal pressure of planets, a finding that could significantly change the current model of planetary formation.Internal Planetary Pressure and the Formation of Core and MantleClick to play embedded YouTube video.
The impacts, such as the one that is thought to have caused the formation of the earth's moon roughly 4.5 billion years ago, could cause random fluctuations in core and mantle pressures that would explain some puzzling geochemical signatures in Earth’s mantle.
"Previous studies have incorrectly assumed that a planet's internal pressure is simply a function of the mass of the planet, and so it increases continuously as the planet grows. What we've shown is that the pressure can temporarily change after a major impact, followed by a longer term increase in pressure as the post-impact body recovers. This finding has major implications for the planet's chemical structure and subsequent evolution," says Simon Lock ...
Giant Impacts Stochastically Change the Internal Pressures of Terrestrial Planets ~ Simon J. Lock, Sarah T. Stewart
- Science Advances 5(9):eaav3746 (04 Sep 2019) DOI: 10.1126/sciadv.aav3746