Newest Mission to Mars: MAVEN
Written by Nancy Atkinson
Did Mars once have a thick atmosphere? Could the climate on the Red Planet have supported water and possibly life in the past? These are the questions NASA hopes to answer in great detail with the newest orbiter mission to Mars. Called the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft, the $485 million mission is scheduled for launch in late 2013. MAVEN is part of the Mars Scout Program, which is designed to send a series of small, low-cost, principal investigator-led missions to the Red Planet. The Phoenix Mars Lander was the first spacecraft selected in this program. "This mission will provide the first direct measurements ever taken to address key scientific questions about Mars' evolution," said Doug McCuistion, director of the Mars Exploration Program at NASA Headquarters in Washington.
Evidence from orbit and the planet's surface points to a once denser atmosphere on Mars that supported the presence of liquid water on the surface. As part of a dramatic climate change, most of the Martian atmosphere was lost. MAVEN will make definitive scientific measurements of present-day atmospheric loss that will offer clues about the planet's history.
"The loss of Mars' atmosphere has been an ongoing mystery," McCuistion said. "MAVEN will help us solve it."
The science team will be led from the University of Colorado at Boulder, and its Laboratory for Atmospheric and Space Physics. The principal investigator for the mission is Bruce Jakosky from UC Boulder. "We are absolutely thrilled about this announcement," said Jakosky. "We have an outstanding mission that will obtain fundamental science results for Mars. We have a great team and we are ready to go."
Artist depiction of the MAVEN spacecraft. Credit: NASA
Lockheed Martin of Littleton, Colo., will build the spacecraft based on designs from NASA's Mars Reconnaissance Orbiter and 2001 Mars Odyssey missions.
MAVEN was evaluated to have the best science value and lowest implementation risk from 20 mission investigation proposals submitted in response to a NASA Announcement of Opportunity in August 2006.
After arriving at Mars in the fall of 2014, MAVEN will use its propulsion system to enter an elliptical orbit ranging 90 to 3,870 miles above the planet. The spacecraft's eight science instruments will take measurements during a full Earth year, which is roughly equivalent to half of a Martian year.
MAVEN's instrument suites include a remote sensing package that will determine global characteristics of the upper atmosphere, and the spacecraft will dip to an altitude of 80 miles above the planet. A particles and fields payload contains six instruments that will characterize the solar wind, upper atmosphere and the ionosphere – a layer of charged particles very high in the Martian atmosphere.
The third instrument suite, a Neutral Gas and Ion Mass Spectrometer will measure the composition and isotopes of neutral and charged forms of gases in the Martian atmosphere
During and after its primary science mission, the spacecraft may be used to provide communications relay support for robotic missions on the Martian surface.
Sources: NASA, UC Boulder
September 17th, 2008 at 7:14 am
Thump, yes, there should have been a thick atmosphere around Mars. You need a thick atmosphere to be able to have liquid water flowing on the surface; if you don't have enough pressure to keep the water liquid, it just sublimates and goes from ice directly to gas. And since there is ample evidence for liquid water flow in the past of Mars, a thick atmosphere must have existed.
Mars is a bit to the small side, but it isn't too small to have a thick atmosphere. Proof of that is Titan, which is smaller than Mars and yet its atmosphere is thicker than the Earth's.
It all depends on a balance between the amount of the so-called "volatiles" available in the planet, the planet's mass (therefore gravity) and the temperature range it shows (and a few more exotic things, like how strong is the planet's magnetic field and if it exists at all).
Besides, all planets lose atmosphere. The Earth is losing its atmosphere. Luckily for us, that loss is veeeery slow, and is probably compensated by new material falling in from interplanetary space. In the case of Mars, we still don't know how and when did Mars lose its atmosphere, and that's what the measurement of today's atmospheric loss will try to determine.
September 17th, 2008 at 4:57 pm
David R. I didn't mean to rock the boat. I'm all for science and probes to Mars to study any aspect. I'm just extremely dissappointed that the search for life on Mars - even microbial life - doesn't get more attention. This question has been unanswered for so long, and none of us live forever. It was a burning question at the dawn of the space age - and then it disappeared. It makes one wonder why.
September 18th, 2008 at 7:24 am
I remember seeing something on TV the other night about Mars losing its atmosphere. It seems there were two factors. One was that, as the core of Mars cooled, it lost its magnetic field and allowed the solar wind access to the atmosphere. The other was also related to cooling. The gases that were being lost to space we no longer being replenished by volcanism.
Made sense to me.
September 18th, 2008 at 9:05 am
@TD
I think that a combination of research will answer that question, including this latest mission. While the folks doing the research haven't necessarily addressed the question you raise head-on, they have produced substantial implicit evidence…e.g., chemistry features of the soil, date re: the atmosphere, geologic history, etc.
I share your sentiment. I would like to see more direct research…but I also realize that the approach to reasearching a planet is very much like assembling a jigsaw puzzle. Every mission produces evidence that will lead to larger conclusions. If you get a chance, get your hands on some of the NASA/JPL-produced documentaries of the Voyager missions. It really puts things in perspective…and might give you some counterbalance to your frustrations re: Mars research.