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On Wednesday, NASA announced the end of a more than 11-year mission aimed at solving a key mystery about Mars: What happened to the air that once made the planet habitable?<\/p>\n
The NASA spacecraft MAVEN, short for Mars Atmosphere and Volatile Evolution, had been orbiting around the Red Planet since 2014. NASA last received a signal from MAVEN on Dec. 6, shortly before the spacecraft passed behind Mars.<\/p>\n
Then the spacecraft stopped responding.<\/p>\n
A review board found that MAVEN began unexpectedly rotating, causing its batteries to drain too quickly and resulting in a loss of power to the communications system.<\/p>\n
\u201cThe team is certainly broken up about this,\u201d said Shannon Curry, the principal investigator of the mission and a scientist at the University of Colorado Boulder, at a news conference on Wednesday. \u201cBut at the same time, we are incredibly proud of the science we\u2019ve accomplished over the last decade.\u201d<\/p>\n<\/div>\n<\/div>\n
NASA officials declined to speculate on the root cause of the mishap. A final report is expected to be released later this year.<\/p>\n
MAVEN launched from Cape Canaveral Space Force Station in Florida in November 2013 as NASA\u2019s first mission dedicated to observing the atmosphere and evolution of Mars. MAVEN reached the Red Planet less than a year later and had been orbiting it ever since, measuring the makeup of the Martian atmosphere and what processes control the escape of air molecules into space.<\/p>\n
Ancient canyons, deltas and river channels on the Martian surface indicate that it once had flowing water, and scientists believe that a thick layer of air surrounding the planet allowed it to stay warm and wet. By studying Mars\u2019s atmosphere, the MAVEN team hoped to find clues as to where that air went, and how that loss transformed Mars from somewhere potentially habitable to the cold, dry planet observed today.<\/p>\n
MAVEN\u2019s original mission was set for only a year, but even before the mission\u2019s launch, scientists thought it could last much longer. The spacecraft\u2019s data helped scientists measure the rate at which Mars\u2019s atmosphere is disappearing and how solar wind \u2014 a stream of hot plasma spewing from the sun \u2014 causes the atmosphere to strip away more rapidly, among other discoveries. MAVEN also observed new types of aurora shimmering above the surface of Mars and captured shots of Comet 3I\/ATLAS, the third object known to originate outside our solar system.<\/p>\n
The spacecraft regularly slipped behind Mars during the mission, which results in a routine communication blackout that usually lasts for about 20 to 30 minutes. But NASA\u2019s Deep Space Network, a collection of radio antennas on the ground, was unable to re-establish communications during the occultation last December.<\/p>\n<\/div>\n<\/div>\n
The mission team made several attempts to recover MAVEN, including a forced reboot of the spacecraft\u2019s computer, through the end of 2025. In January, a radio telescope at the Green Bank Observatory in West Virginia also searched for the spacecraft. Those efforts were ultimately unsuccessful.<\/p>\n
NASA formed a review board for the spacecraft\u2019s future in February and found that MAVEN was operating normally in the weeks leading up to its loss of signal. By the time the spacecraft emerged from behind Mars, however, the orbiter was operating in a so-called safe mode and has been radio silent ever since.<\/p>\n
The review board was able to recover fragments of data from the spacecraft, and discovered that MAVEN was spinning at about 2.7 revolutions per minute. This was unusual, according to Mike Moreau, a project manager for the mission, as MAVEN is not supposed to rotate at all.<\/p>\n
\u201cThat indicates a problem that the spacecraft probably couldn\u2019t recover from,\u201d he said at the news conference.<\/p>\n
The board concluded that MAVEN was unrecoverable. In addition to not being able to continue its science operations, the spacecraft was no longer able to relay data between Mars and Earth, a key point of connection to support NASA rovers exploring the Martian surface.<\/p>\n<\/div>\n<\/div>\n
According to Tiffany Morgan, director of NASA\u2019s Mars Exploration Program, other orbiters that belong to both NASA and the European Space Agency will be able to pick up the slack in relaying communications. But the loss of MAVEN will cause \u201ca slight delay\u201d in getting science data back to Earth, she said.<\/p>\n
MAVEN is expected to circle Mars for the next 50 to 100 years, at which point the orbit of the spacecraft will degrade enough for it to burn up in the planet\u2019s atmosphere. MAVEN will no longer be able to supplement data for NASA\u2019s ESCAPADE mission, which launched in November to further study Mars\u2019s atmosphere.<\/p>\n
At the news conference, Dr. Curry explained that MAVEN enabled scientists to study the processes behind Mars\u2019s disappearing atmosphere in greater detail than on any other planet, including Earth.<\/p>\n
When asked about what she would write on MAVEN\u2019s tombstone, she responded: \u201cBest. Mars. Mission. Ever.\u201d<\/p>\n<\/div>\n<\/div>\n