SAN FRANCISCO — Recent discoveries suggesting that abundant water once flowed on the surface of Mars are heightening anticipation of the Mars Atmosphere and Volatile Evolution (MAVEN) mission, a NASA mission designed to explain what happened to that water, according to MAVEN Principal Investigator Bruce Jakowsky of the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado, Boulder.
Scheduled for launch in 2013, MAVEN will use eight onboard instruments to gather data on the current composition of the martian atmosphere and discover the process that continually strips away the red planet’s carbon dioxide and water. With that data, scientists hope to learn not only how the climate of Mars is changing today, but how changes over the last 4 billion years have affected the ability of the planet to support life.
“We are trying to understand the history of the climate, the history of the atmosphere and the way that affects things like the availability of liquid water,” Jakowsky said. “If Mars was warmer in the past and liquid water was stable on the surface, why did that change?”
NASA announced plans for the MAVEN mission in September 2008 and pledged $485 million to support it following an evaluation of 20 competing projects. Last August, the MAVEN team completed a thorough review of program requirements. Now, spacecraft and instrument teams are drafting systems and components in anticipation of a preliminary design review scheduled for July 2010, according to David Mitchell, MAVEN project manager at the NASA Goddard Space Flight Center in Greenbelt, Md.
To limit cost and risk, MAVEN draws heavily on previous missions. The spacecraft’s structure, avionics, propulsion, telecommunications and attitude control components are either identical or very similar to those on NASA’s Mars Reconnaissance Orbiter, said Guy Beutelschies, MAVEN deputy program manager for Denver-based Lockheed Martin Space Systems. Even the spacecraft’s instruments are based on models flown in previous missions, Jakowsky said.
One major difference between the two spacecraft is that while the Mars Reconnaissance Orbiter remains pointed toward the martian surface and uses moveable solar arrays, MAVEN will focus on the sun and include fixed solar arrays. The three MAVEN instruments that need to point toward the planetary surface, the Suprathermal and Thermal Ion Composition built by the Space Sciences Laboratory at the University of California, Berkeley, LASP’s Imaging Ultraviolet Spectrometer and Goddard’s Neutral Gas and Ion Mass Spectrometer, will be installed on a payload platform attached to the end of a 1-meter boom, Jakowsky said.
MAVEN will investigate Mars’ magnetic field, atmospheric particles and how those particles interact with the solar wind — the stream of charged particles emanating from the sun’s corona — with a magnetometer built by Goddard and four instruments built by the Berkeley Space Sciences Laboratory: a Solar Wind Electron Analyzer; a Solar Wind Ion Analyzer; a Solar Energetic Particle instrument and Langmuir Probe and Waves, a device that monitors escaping ions and extreme ultraviolet energy from the sun.
Early next year, Lockheed Martin officials plan to construct the first MAVEN component, a prototype of the key interface electronics card that links the spacecraft electronics with the payload electronics. “This interface card is absolutely critical to making sure that we operate the instruments correctly,” Beutelschies said. “We are going to build a prototype card that will enable us to iron out the bugs.”
During the summer of 2011, space agency officials plan to conduct a critical design review of all hardware and software. Once that is completed, spacecraft and instrument teams will begin building flight systems. By the summer of 2012, Lockheed Martin officials plan to begin assembling and testing the MAVEN spacecraft before sending it to Florida’s Kennedy Space Center in August of 2013.
On Nov. 18, 2013, MAVEN is scheduled for launch on a Atlas 5 or Delta 4 rocket built by United Launch Alliance of Denver. Ten months later — on Sept. 16, 2014 — MAVEN will begin its 4.5 hour elliptical orbit around Mars, Mitchell said.
Although the MAVEN launch is four years away, Mitchell said he is concentrating on keeping the mission on schedule. “The biggest challenge with any Mars mission is the tight planetary window,” Mitchell said. “In Maven’s case, there is a 20-day window. If we miss that, we wait 26 months for the next opportunity.”
Once the MAVEN spacecraft reaches Mars, science teams plan to gather data for one Earth year, which represents half the time it takes for Mars to orbit the sun. “From where we sit today, we think one Earth year would let us get the measurements we need,” Jakowsky said. “That doesn’t mean we will be done with the science. I can provide a long list of reasons to extend the mission beyond one year. And when the time comes, we will have that discussion with NASA and hope they will fund it to address different science objectives.”
Recent missions to Mars, including NASA’s Mars Reconnaissance Orbiter, Mars Exploration Rovers, Mars Odyssey Orbiter, Phoenix Mars Lander and the European Space Agency’s Mars Express, are providing compelling evidence that Mars once featured lakes and rivers, which disappeared during dramatic climate shifts. MAVEN seeks to explain how and why those changes occurred, Jakowsky said.
Since MAVEN is the first Mars mission managed by Goddard, program officials there are working closely with the Jet Propulsion Laboratory (JPL) in Pasadena, Calif., the NASA center responsible for previous trips to Mars. In addition to sharing the lessons of earlier missions, JPL is responsible for navigating the MAVEN spacecraft, Mitchell said.
