MAVEN will make detailed measurements of the Red Planet's atmosphere from orbit, helping scientists understand why and how Mars' climate has changed so dramatically over the last few billion years.
Here are 10 things to keep in mind about the MAVEN probe and its $671 million mission.
FIRST STOP: MAVEN is Big
And MAVEN weighs 5,410 pounds (2,454 kilograms) — as much as a fully loaded SUV. [How NASA's MAVEN Mars Orbiter Works (Infographic)]
NEXT: Long Road to Mars
This 10-month journey is significantly longer than the trek endured by the Mars rover Curiosity, the last Red Planet explorer NASA launched. Curiosity reached Mars on Aug. 5, 2012, about 8.5 months after blasting off from Cape Canaveral, Fla., on Nov. 26, 2011. [NASA's MAVEN Mission to Mars (Photos)]
NEXT: Elliptical Orbit
In addition, MAVEN will make a handful of "deep dips" during the course of its mission, coming within 77 miles (124 km) of the Martian surface on five separate occasions. MAVEN will thus be able to sample the upper atmosphere of Mars directly and get a wider view of the entire planet from afar — a powerful combination, NASA officials say.
NEXT: A Martian Detective
Scientists hope MAVEN helps them get a better handle on this dramatic shift. The mission aims to determine how and why much of the Martian atmosphere was lost to space, and what role this loss played in Red Planet climate change over the last four billion years.
MAVEN will use eight different science instruments to study Mars' upper atmosphere and the solar wind, the stream of charged particles flowing from the sun that is thought to have stripped away much of the water and other volatile compounds in the Red Planet's air.
NEXT: No Search for Life
In fact, MAVEN is not equipped to sniff for methane, a gas that could be an indicator of extant life. (About 90 percent of Earth's methane is produced by living organisms.) MAVEN's budget could not support adding a methane-detection component, mission scientists have said. [The Search for Life on Mars (Photo Timeline)]
NEXT: A Communications Cog
NASA currently has two rovers exploring the Red Planet's surface — the car-size Curiosity and its smaller cousin Opportunity, which landed in January 2004. MAVEN will augment data relay from the two robots, which is currently provided by two NASA orbiters — Mars Odyssey, which launched in 2001, and the Mars Reconnaissance Orbiter, (MRO), which blasted off in 2005.
NEXT: Government Shutdown Drama
This caused a bit of anxiety; if MAVEN misses its current launch window (which runs through Dec. 15), it would have to wait another 26 months for the next favorable alignment of Earth and Mars.
While the shutdown dragged on for more than two weeks, MAVEN's limbo lasted just two days. NASA — which had furloughed 97 percent of its employees and ceased most operations — granted the mission an emergency exception, chiefly because of its importance as a communications link. (The agency has no relay orbiters on the books beyond MAVEN.)
NEXT: Lucky Number 10!
Most of these past missions have been successful, with a few notable exceptions. For example, the agency lost contact with its Mars Observer probe in August 1993, shortly before it was slated to enter orbit around the Red Planet. And the Mars Climate Observer was lost on arrival in September 1999, likely burning up in the planet's atmosphere. [Occupy Mars: Robotic Missions to the Red Planet (Infographic)]
NEXT: Mars Orbiter of the People
For instance, people around the world submitted more than 12,500 haikus in response to a MAVEN contest. Any poem receiving more than two votes from the public made its way onto a DVD that's flying with the spacecraft to Mars.
Also going to the Red Planet in digital form are 377 pieces of student artwork submitted in response to another MAVEN competition. Five winners were selected during this contest, which tallied a total of more than 82,000 public votes, mission officials said.
NEXT: A Martian Tag Team with Curiosity
Curiosity is currently sampling the Martian atmosphere at ground level using its Sample Analysis at Mars instrument suite, or SAM. SAM's results should help guide the interpretation of MAVEN's findings many miles above, NASA officials have said.
Find the latest MAVEN news, photos and videos on SPACE.com.
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