Ten Years at Mars with NASA’s MAVEN Mission | NASA Goddard
In celebration of this mission milestone, we recap examples of the most significant scientific results of this unique and long-lasting Mars aeronomy mission:
Extreme atmospheric erosion
One of MAVEN’s first big results was discovering that the erosion of Mars’ atmosphere increases significantly during solar storms. The team studied how the solar wind—a stream of charged particles continually streaming from the Sun—and solar storms continually strip away Mars’ atmosphere, and how this process played a key role in altering the Martian climate from a potentially habitable planet to today’s cold, arid planet.
Sputtering to space
To better understand how Mars lost much of its atmosphere, MAVEN measured isotopes of argon gas in the upper Martian atmosphere. Argon is a noble gas, meaning it rarely reacts with other constituents in the Martian atmosphere. The only way it can be removed is by atmospheric sputtering—a process where ions crash into the Martian atmosphere at high enough speeds that they knock gas molecules out of the atmosphere. When the MAVEN team analyzed argon isotopes in the upper atmosphere, they were able to estimate that roughly 65% of the argon originally present had been lost through sputtering over the planet’s history.
A new type of aurora
MAVEN has discovered several types of auroras that flare up when energetic particles plunge into the atmosphere, bombarding gases and making them glow. The MAVEN team showed that protons, rather than electrons, create auroras at Mars. On Earth, proton auroras only occur in very small regions near the poles, whereas at Mars they can happen everywhere.
Martian dust storm
In 2018, a runaway series of dust storms created a dust cloud so large that it enveloped the planet. The MAVEN team studied how this “global” dust storm affected Mars’ upper atmosphere to understand how these events affect how the escape of water to space. It confirmed that heating from dust storms can loft water molecules far higher into the atmosphere than usual, leading to a sudden surge in water lost to space.
Map of Martian winds
MAVEN researchers created the first map of wind circulation in the upper atmosphere of Mars. The new map is helping scientists better understand the Martian climate, including how terrain on the planet’s surface is disturbing high-altitude wind currents. The results provide insight into how the dynamics of the upper Martian atmosphere have influenced the Red Planet’s climate evolution in the past and present.
Twisted tail
Mars has an invisible magnetic “tail” that is twisted by its interaction with the solar wind. Although models predicted that magnetic reconnection causes Mars’ magnetotail to twist, it wasn’t until MAVEN arrived that scientists could confirm that the predictions were correct. The process that creates the twisted tail could also allow some of Mars’ already thin atmosphere to escape to space.
Mapping electric currents
Researchers used MAVEN data to create a map of electric current systems in the Martian atmosphere. These form when solar wind ions and electrons smash into the planet’s induced magnetic field, causing the particles to flow apart. The resulting electric currents, which drape around the planet, play a fundamental role in the atmospheric loss that transformed Mars from a world that could have supported life to an inhospitable desert.
Disappearing solar wind
MAVEN recently observed the unexpected “disappearance” of the solar wind. This was caused by a type of solar event so powerful that it created a void in its wake as it traveled across the solar system. MAVEN’s measurements showed that when it reached Mars, the solar wind density dropped significantly. This disappearance of the solar wind allowed the Martian atmosphere and magnetosphere to balloon out by thousands of kilometers.
Ultraviolet views of the Red Planet
MAVEN captured stunning views of Mars in two ultraviolet images taken at different points along the Red Planet’s orbit around the Sun. By viewing the planet in ultraviolet wavelengths, scientists gain insight into the Martian atmosphere and view surface features in remarkable ways.
MAVEN’s principal investigator is based at the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder. LASP is also responsible for managing science operations and public outreach and communications. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the MAVEN mission. Lockheed Martin Space built the spacecraft and is responsible for mission operations. NASA’s Jet Propulsion Laboratory in Southern California provides navigation and Deep Space Network support.
Learn more about MAVEN:
https://lasp.colorado.edu/maven/
https://science.nasa.gov/mission/maven/
Video Credit: NASA's Goddard Space Flight Center
Duration: 6 minutes
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