The basic theory about planetary design is that the planets began to collect these variables from the nebula around a small star, says Sandrine Péron, a postdoctoral scientist working with Professor Sujoy Mukhopadhyay in the Department of Earth and Planetary Science, University of California, Davis.
Because the planet is a molten rock at this point, these elements first dissolve into magma ocean and then return to space. Later, chondritic meteorites hit a dwarf planet bringing the most variable aspects.
Scientists, therefore, expect that the elements in our solar system must reflect the formation of solar and nebulae or a mixture of solar and meteoritic volatile. At the same time, atmospheric mutations would be more common in meteorites. These two sources — solar vs. chondritic-can be separated by concentrations of isotopes of noble gases, especially krypton.
Mars is fascinating because it builds relatively quickly — it hardened some four million years after the birth of the Solar System. In comparison, the Earth took 50 to 100 million years to make.
“We can rebuild the history of flexible delivery in the first few years of the Solar System,” Péron said.
Meteorite from within Mars
Some meteorites fall to Earth from Mars, and most come from rocks high up in the atmosphere of Mars. The Chassigny meteorite, which landed on Earth in northeastern France in 1815, is unusual because it is thought to represent the planet’s interior.
By making more precise minute estimates of krypton isotopes in meteorite samples using a new method developed at the UC Davis Noble Gas Laboratory, researchers can find the origin of the elements in the rock.
“Because of their small size, krypton isotopes are difficult to measure,” Péron said.
Surprisingly, krypton meteorite isotopes are associated with those from chondritic meteorites, not solar and nebulae. That means meteorites bring evolving elements to a constructive planet much earlier than previously thought and before the nebula, which undermines everyday thinking.
“The Martian interior of krypton is almost chondritic, but the atmosphere is sunny,” Péron said. “It’s very different.”
The results show that Mars’ atmosphere could not have evolved from the atmosphere, as that would have given it a chondritic formation. The planet must find space in the solar nebula after the sea magma cools down to prevent massive mixing between internal chondritic gases and solar gases.
New results suggest that Mars’ growth was halted before the Sun’s rays destroyed the solar nebula. But radiation was also supposed to remove the nebular atmosphere from Mars, suggesting that atmospheric krypton must have been somehow preserved, possibly trapped underground or in tropical ice.
“However, that would require Mars to freeze immediately after its discovery,” Mukhopadhyay said. “Although our research clearly identifies the chondritic gases within the Martian, it also raises interesting questions about the origin and formation of the first Mars universe.”