What Happened to Mars’ Atmosphere?

The Earth-like atmosphere that once existed on Mars seems to have been blown away by solar wind, according to new findings from NASA’s ongoing exploration of the red planet.

In a press conference Thursday, the space agency confirmed that solar wind played a major role in the disappearance of the Mars’ atmosphere and water.

The discovery, published in the journals Science and Geophysical Research Letters, sheds new light on how the planet evolved from having a warm and wet environment that might have hosted life to becoming the cold, arid world it is today. Solar winds did have the same effect on Earth due to our planet’s strong magnetic fields.

MOAR Possible Signs Of Ancient Microbial Life On Mars

This starting to get out of hand.

Weeks after Curiosity detected spikes of methane in the Martian atmosphere, possible evidence of biological activity, a prominent geo-biologist says she sees possible signs of past life in photos of the Martian landscape taken by the rover.

Nora Noffke, an associate professor at Old Dominion University, looked at the structures seen in rocks on Mars and compared them to geological structures on Earth that are formed by microbes living in communities called microbial mats.

The structures belong to a group of microbial structures that form by the interaction of benthic (living on the ground) microbes with sediment dynamics (erosion) in clastic deposits such as sand.

In other words, if such structures do exist on Mars, that suggests the planet may have once harbored microbial life. The microbes would have existed on Mars less than 3.7 billion years ago, according to Noffke.

In the abstract to a paper describing her research, Noffke detailed the similarities found between the structures on Earth and Mars:

“The microbially induced sedimentary-like structures (MISS) identified in Curiosity rover mission images do not have a random distribution. Rather, they were found to be arranged in spatial associations and temporal successions that indicate they changed over time. On Earth, if such MISS occurred with this type of spatial association and temporal succession, they would be interpreted as having recorded the growth of a microbially dominated ecosystem that thrived in pools that later dried completely.”

 

New Clues for Life on Mars

NASA’s Curiosity rover detected a strange burst of methane gas in the atmosphere on Mars, along with other organic chemicals in rocks on the planet’s surface. These findings are raising new questions about the planet’s habitability today as well as in the past.

Using its onboard Sample Analysis at Mars (SAM) laboratory, the rover “sniffed” more than a dozen samples of the Martian atmosphere over a 20-month period. Grotzinger and his team found that methane levels shot up tenfold to an average of seven parts per billion over two months in late 2013 and early 2014, according to NASA.

The researchers aren’t sure what caused the burst, but they’ve offered two potential explanations: an interaction between water and rocks called serpentization, or methane-belching microbes. Anaerobic bacteria produce around 95 percent of the methane on Earth.

Curiosity found other organic (carbon-containing) molecules in powder collected from drilling into an ancient rock called Cumberland.

The researchers say this is the first definitive evidence of organics found on the surface of Mars. While the presence of organics doesn’t prove that life existed on ancient Mars, it suggests the planet may have had the ingredients required for life.

A paper describing the detection of methane was published online on Dec. 16 in the journal Science.

Meteorite Stirs Debate About Live on Mars (Again)

An international team of researchers say they’ve found evidence of biological activity inside a meteorite that fell to Earth from Mars three years ago–in other words, possible evidence that there was once life on the red planet.

The meteorite in question is the “Tissint” specimen, which fell on the Moroccan desert on July 18, 2011.

As a  team of researchers report in a new paper, chemical, microscopic, and isotope analyses show traces of organic carbon within tiny fissures in the space rock, and that the carbon had to have been deposited before the rock left Mars.

Other scientists say that the meteorite could have been contaminated with carbon from terrestrial sources, even if the carbon did originally come from Mars.

Scientists also point out that a biological origin is not the only possible explanation for the carbon found in the meteorite. Other possibilities include volcanic and/or hydrothermal activity on Mars which could permeate Tissint with carbon-bearing fluids.

The study was published online in the journal Meteoritics and Planetary Science on November 26, 2014.