|Courtesy of NASA.|
MAVEN, which stands for Mars Atmosphere and Volatile EvolutioN orbiter, is the new Martian mission of the American space agency after Curiosity, which was launched two years ago. The spacecraft will reach the Red Planet in ten months and exactly on
22 September 2014. She will not land but will remain
in an elliptical orbit between 150 and 6000 km above the surface of the
planet, with some additional approaches up to 124 km. Her task will
be to study the Martian atmosphere, as it is now, collecting data that
will let us understand how it was in the past and why it changed.
Approximately 4 billion years ago, in fact, Mars was a planet very similar to Earth, with a thick atmosphere allowing the existence of water in the liquid state and, consequently, of life. We have not yet evidence that there has been life on Mars in the past (or maybe there is now), but now we are certain that a long time ago the Red Planet was not red at all. It had oceans, lakes and rivers, traces of which are still present on its desert surface.
What has happened?
What has transformed Mars from a habitable planet into the desert it is today?
MAVEN will try to answer to these questions, trying to identify the causes of the loss of the Martian atmosphere. To do so she will bring eight different scientific instruments onboard with which she will study the upper atmosphere of the planet and the solar wind. The latter is a stream of charged particles coming from the sun, which are believed to have ripped off water vapour and other volatile compounds in the atmosphere of Mars, reducing it to a pressure of just 1% of the Earth’s one.
This information will allow researchers to understand the habitability of the Red Planet, both past and present, although it cannot provide evidence of the actual existence of life on Mars.
The orbiter will also act as a relay for transmissions between Mars and Earth, allowing a greater flow of data from the two rovers on the surface, Curiosity (launched in 2011) and Opportunity (launched in 2004), currently dependent on two other NASA satellites: the Mars Odyssey, launched in 2001, and the Mars Reconnaissance Orbiter, launched in 2005.
MAVEN will team up with Curiosity, which is already exploring the Martian lower atmosphere thanks to her SAM (Sample Analysis at Mars) instrument suite.
You can follow the launch of the MAVEN mission directly on NASA TV: www.nasa.gov/multimedia/nasatv
In the animation from NASA below you can see how Mars was 4 billion years ago and how that has changed over time.