NASA's next mission to Mars will do one specific thing -- it will analyze the red planet's atmosphere in an effort to peel back the mystery of its evolution and try to understand why it thinned out so drastically, turning a once wet world into a barren wasteland. The $671 million Mars Atmosphere and Volatile EvolutioN (MAVEN) orbiter, which is scheduled for launch at 1:28 p.m. EST on Nov. 18, is a Martian climate change probe capable of making unprecedented observations of the planet's atmosphere. It will even, on occasion, swoop low to directly sample the tenuous upper atmospheric gases. MAVEN is the latest in a series of Mars missions that are piecing together Mars' water history, organic chemistry and past and present habitability.
Shown here, MAVEN sits atop an Atlas V rocket at Space Launch Complex 41, Cape Canaveral Air Force Station, Fla., before launch on Monday afternoon.
After launch, MAVEN will take 10 months to reach its destination, arriving in Mars orbit on Sept. 22, 2014. NASA's previous Mars mission -- the Mars Science Laboratory's Curiosity rover -- took only 8 months to reach Gale Crater, arriving on Aug. 6, 2012. Interestingly, MAVEN isn't the only orbiter with a planned rendezvous in September 2014. The Indian Mangalyaan Mars Orbiter Mission (MOM), which launched on Nov. 5, is scheduled to arrive at Mars two days after MAVEN, on Sept. 24, 2014. Mangalyaan is taking a little longer to get to Mars due to its series of Earth flybys that have gradually increased its speed and orbital distance, eventually propelling it Mars-wards.
When it arrives in Mars orbit, MAVEN will be the beefiest satellite in the current Mars orbiter fleet; NASA's Mars Reconnaissance Orbiter (MRO), NASA's Odyssey and Europe's Mars Express are all lightweights in comparison. MAVEN (the spacecraft plus propellents) weighs 2,550 kilograms (5,620 pounds) at launch. In comparison, the MRO was 2,180 kilograms (4,810 lb), Odyssey was 376 kilograms (829 lb) and Mars Express was 1,123 kg (2,476 lb) at launch. The ISRO's Mangalyaan spacecraft has a launch mass of 1,337 kg (2,948 lb). In addition to its impressive mass, MAVEN has a "wingspan" (from one end of deployed solar panels to the other) of 11.4 meters (37.5 feet).
Once encircling Mars, MAVEN will have a rather extreme orbit. At closest approach (perapsis), MAVEN will zoom within 150 kilometers (93 miles) of the Martian surface. But due to its planned highly elliptical orbit, the satellite will fly out to a maximum distance (apsis) of 6,000 km (3,728 miles). On 5 occasions during its primary mission, MAVEN will drop even lower on close approach, coming to within 124 km (77 miles) of the surface. On those occasions, MAVEN will be able to directly sample some of the upper atmospheric gases and analyze them.
What happened to Mars? Evidence is piling up that the red planet used to have more in common with Earth in its early history. We know that large bodies of water used to persist across what are now barren, dry plains. Rivers even used to flow, eroding Mars rock into pebbles. The puzzle of Mars' predominantly dry appearance can be blamed on its atmosphere -- an atmosphere with a pressure of 1 percent that of Earth's. What atmospheric processes caused Mars to lose its water? MAVEN will take on this challenge to try to understand whether the atmosphere was vented into space naturally; if the water was lost through atmospheric processes or is currently locked in the Martian crust; and try to understand the interplay between the sun's ferocious solar wind and Mars' upper atmosphere.
MAVEN is carrying 8 sophisticated instruments all designed to tackle every aspect of Mars' climate history and how the planet's atmosphere interacts with interplanetary space. MAVEN's suite of instrumentation will: directly sample atmospheric gases; spectroscopically analyze the atmospheric composition; measure the planet's magnetic field and the interplanetary magnetic field; detect the interaction of energetic solar particles with atmospheric gases; and analyze ionospheric heating. The Neutral Gas and Ion Mass Spectrometer (NGIMS) package will be used to measure the isotopes of atmospheric gases. These data, in turn, will be compared with the Mars Science Laboratory's isotopic analyses, aiding a better understanding of how much of the atmosphere has been lost over time.
Sadly, due to budget constraints, MAVEN does not have an instrument to detect atmospheric methane. Other missions have detected trace amounts of the organic compound that may or may not be linked with microbial life on Mars. Most recently, Curiosity was used to "sniff" the air around Gale Crater for any sign of the gas -- it detected none, only adding to the mystery surrounding Mars' methane mystery.
The current Mars orbiters aren't only carrying out science; they also form an essential relay network for communications between Earth and NASA's rover missions (and future surface missions). MAVEN is packing a powerful Electra radio system that will contribute to the communications between Curiosity, Opportunity and mission control, allowing a data transfer rate of up to 10Mbps.