Mars May Have Been Colder Longer Than Originally Thought

NASA’s Johnson Space Center lead author Paul Niles, discusses how suflate minerals on Mars, previously indicated a warm past climate, can now tell us more about planet’s extremely cold temperatures.

“The scenario described in our paper represents a completely different weathering regime from anything preserved in Earth’s geologic record and it is made possible by volcanism in a subfreezing environment on a planet without an ocean,” said Niles.

Niles and his co-authors (Douglas Ming, also of NASA’s Johnson Space Center; Joseph Michalski, a scientist formerly from the Natural History Museum, London; and D.C. Golden with the Engineering and Science Contract Group at Jacobs Technology) are suggesting that sulfate-rich deposits on Mars could be formed at much colder temperatures without water. NASA says the deposits actually come from a period of intense volcanic outgassing in a cold, dry climate, where ash and dust were exposed to thin films of acidic solutions at temperatures well below 0 degrees Celsius.

Does it have something in common with our planet?

They believe Mars was warm and wet even after losing its magnetic field. Getting this conclusion was necessary to examinate the sulfate deposits on Earth, which are generally thought to occur due to evaporation of water bodies.

“When you combine the results of our experiments with studies of sulfates in ice deposits in Greenland and Antarctica and the polar regions on Mars, you get a compelling argument that sulfate formation at super cool temperatures is not only possible, but would likely be unavoidable on Mars. The evidence clearly shows that cryogenic weathering can operate, even under the extremely cold current Martian conditions,” said Niles.

The researchers’ experiment subjected fine-grained particles, similar to what would have been found on Mars, to an acidic solution that had been cooled to temperatures well below zero-degrees Celsius. Instead of just slowing down the reaction rate, the cold temperatures actually created a concentrated acid solution that enhanced dissolution rates despite the cold temperatures.

 

 

source: nasa.gov