NASA reports change on Mars: It has started to 'breathe'

The Mars Atmosphere and Volatile Evolution (or MAVEN for short) spacecraft has been orbiting Mars since September 2014 to study how the planet has lost its atmospheric gases over the ages. In December 2022, MAVEN witnessed an unexpected expansion phase of the Martian atmosphere.

NASA announced that the spacecraft detected a dramatic "disappearance" in the flow of charged particles that make up the solar wind. This phenomenon was caused by a rare and powerful solar event strong enough to create a "void" as it traveled throughout the entire Solar System.

CHANGE IN THE MARTIAN ATMOSPHERE

According to the report by Donanımhaber, like other planets in our small cosmic neighborhood, Mars is constantly exposed to solar wind. Solar wind is a stream of electromagnetically charged particles released from the corona, the Sun's upper atmosphere, and it permeates every planet and cosmic object in the Solar System. When there is a change in the amount of charged particles, unexpected and extreme atmospheric events can be observed. Therefore, due to the Sun being the Sun, like all planets in our system, Mars is constantly exposed to solar wind.

This exposure exerts pressure on the magnetosphere and ionosphere of unprotected planets, stripping the atmosphere away from the planet and dragging it into space over time. However, for two days last December, a portion of this wind disappeared. On December 25, the sudden and dramatic disappearance of the wind caused the atmosphere on the side of Mars facing the Sun to swell to nearly four times its normal size—rising from its usual 800 km to over 3,000 km. This strange event was recorded by the NASA orbiter MAVEN, which has been observing both Mars' atmosphere and its response to the Sun's behavior since 2014.

NEVER SEEN BEFORE

Jasper Halekas, a professor of physics and astronomy at the University of Iowa and a member of the MAVEN team, said in a statement, "We are really in uncharted territory here. This is something we have never seen before on Mars with MAVEN."

So how did this happen?

This unusual event, a first in MAVEN's nearly decade-long career, occurred when a fast-moving region of solar wind overtook a slower one, sweeping up the materials of the latter and leaving a sparse region behind. However, this effect was not permanent, and the atmosphere returned to its normal state just two days later.

Shannon Curry, MAVEN's principal investigator, stated that the extreme conditions observed in 2022 were "scientifically invaluable" because they allowed scientists to see how Mars might behave if it were orbiting a less "windy" star. Meanwhile, a similar event occurred on Earth in 1999, when our planet's atmosphere expanded to five times its normal size.