NASA’s MAVEN probe reveals speed of solar winds stripping Martian atmosphere

Now they know why.

The first scientific results from the MAVEN mission were published online on Thursday, November 5, in a series of papers in the journals Science and Geophysical Research Letters. Instead, the Martian magnetic field is weak and diffuse, likely because a strong, ancient, and Earth-like magnetic field imprinted itself in metallic Martian rocks before it faded away eons ago.

About 3.8 billion years ago, Mars was a reasonably pleasant place. This wind carries magnetic fields and when these hit the planet they generate electric fields that are then able to accelerate atmospheric ions, hurling them either directly off into space or slamming them into other atmospheric constituents so that they are removed. Over time, Mars lost its atmosphere to become the cold, barren planet observed in 2015.

The Curiosity Rover found evidence of lakes, rivers and minerals on Mars, a surface that apparently once resembled Earth but is now barren and frozen. The consequences for any life that might have existed nearly certainly would have been disastrous. The solar wind was a leading candidate. The second way is simpler; entire atmospheric particles can be knocked into space by colliding solar particles. The solar winds are really just a mass of speeding protons and electrons that enter Mars’ atmosphere at a rate that kills your marathon pace at 1 million miles per hour.

The Northern Lights are tied to the magnetism of the Earth’s poles, whereas Mars’ aurora may be tied to the “remnant magnetic field of the crust”.

All of this, as NASA begins recruiting astronauts to prepare for this unprecedented journey to better understand the mysterious red planet.

The announcement is great news for the MAVEN team, and the probe will continue in an extended mission to gather more data. Earlier in our solar system’s history, these storms were more frequent and intense.

The new findings should have little effect on NASA’s efforts to send humans to Mars.

“The removal of atmosphere from Mars by episodic extreme events may have been very important over Mars’ history, just as a single tsunami can remove a portion of the ocean shore that would have taken millennia to erode by the steady lapping of the tides”, Halekas said. But there’s no rush. And ongoing solar influence can remove these gases at the rate of about 100 grams, or a quarter-pound, of particles every second – enough to remove the atmosphere in a few billion years. Scientists came to this conclusion based on the grains and distribution of dust on Mars’ surface, which ruled out Martian moons Phobos and Deimos as the culprits. Magnetospheres offer a shield against solar winds, and mapping these pockets of protection was key to measuring how effective solar winds were at dissolving the Martian atmosphere.