Happy Anniversary, MAVEN! NASA Mars Probe Marks 2 Years of Science Work

Artist's impression of the MAVEN
Artist's illustration of NASA's MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft orbiting the Red Planet. (Image credit: NASA)

NASA's newest Mars orbiter has now been on the job for two Earth years, investigating how the Red Planet lost its atmosphere in the ancient past. 

The Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft reached Mars on Sept. 21, 2014, and officially began its science mission less than two months later, on Nov. 16 of that year.

MAVEN — the first orbiter tasked with studying Mars' atmosphere as its primary task — has made a number of interesting discoveries over the past two years. In 2015, for example, MAVEN's measurements allowed mission scientists to determine just how quickly Mars' atmospheric gases escape to space today — at an average rate of about 4 ounces (100 grams) per second. [NASA's MAVEN Mars Mission in Photos]

"Taken together, the MAVEN results tell us that loss of gas from the atmosphere to space has been the major force behind the [Martian] climate having changed from a warm, wet environment to the cold, dry one that we see today," MAVEN principal investigator Bruce Jakosky, of the University of Colorado Boulder, said in a NASA statement.

MAVEN's data suggest that Mars had lost most of its atmosphere by about 3.7 billion years ago, mission scientists have said. For perspective, researchers think that life first appeared on Earth around 4 billion years ago.

The orbiter also spotted a cloud around Mars that likely consists of interplanetary dust. In addition, in a layer of the atmosphere known as the ionosphere — the zone where auroras occur — MAVEN found a layer of metal ions, or charged particles. These are produced when interplanetary dust falls into the atmosphere.

Some side observations have also yielded interesting results. For example, Mars has no global magnetic field, yet MAVEN found ultraviolet auroras spreading over the planet's northern hemisphere. The spacecraft also detected a stream of ions flying into space that had never been spotted before.

Though MAVEN's science mission officially began on Nov. 16, 2014, the orbiter started doing some science work in October of that year. One of MAVEN's earliest tasks was to observe Comet Siding Spring make a close flyby of Mars on Oct. 19, 2014, to see what effects the comet had on Mars' atmosphere.

NASA recently announced that MAVEN has achieved all of its science objectives, and that MAVEN has been granted a two-year mission extension that will keep it operating through at least September 2018.

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Elizabeth Howell
Staff Writer, Spaceflight

Elizabeth Howell, Ph.D., is a staff writer in the spaceflight channel since 2022. She was contributing writer for Space.com (opens in new tab) for 10 years before that, since 2012. Elizabeth's reporting includes an exclusive with Office of the Vice-President of the United States, speaking several times with the International Space Station, witnessing five human spaceflight launches on two continents, working inside a spacesuit, and participating in a simulated Mars mission. Her latest book, "Why Am I Taller?", is co-written with astronaut Dave Williams. Elizabeth holds a Ph.D. and M.Sc. in Space Studies from the University of North Dakota, a Bachelor of Journalism from Canada's Carleton University and (soon) a Bachelor of History from Athabasca University. Elizabeth is also a post-secondary instructor in communications and science since 2015. Elizabeth first got interested in space after watching the movie Apollo 13 in 1996, and still wants to be an astronaut someday. Mastodon: https://qoto.org/@howellspace