MAVEN in orbit above Mars (Depiction from NASA)
The MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft has been on its Mars orbit mission since Sept. 21, but it is likely few know how remarkable it is. Consider this fist, if you think you know everything about it: It left Earth in November last year with 425 gallons of fuel. That's correct, you read it right. And further, of this 425 gallons, no more than 25 gallons were allotted for the actual journey to Mars. Part of that allotment designated for 4 trajectory correction maneuvers to keep the craft on course- but only two were actually required consuming 5 gallons- so the extra fuel can be used to extend its mission.
The orbit of the spacecraft will be adjusted over the next 6 weeks or so from its current 35 hour period orbit to a 4 1/2 hour science orbit. Since the period is related to the semi-major axis by Kepler's 3rd law, we infer from this that the orbital dimensions will be significantly smaller, the orbit 'tighter'. A depiction is shown below:
What is MAVEN's mission?
Mars atmosphere "out-gassed" a long time ago and MAVEN' mission is to discover what happened to this early atmosphere. The existing evidence shows that Mars had liquid water flowing over its surface at one point, perhaps 1 billion years ago. This conceivably was an indicator of an environment that could support life.
The goal of MAVEN then is to determine the history of the loss of atmospheric gases to space, providing answers about Martian climate evolution. By measuring the rate with which the atmosphere is currently escaping to space and gathering enough information about the relevant processes, scientists will be able to infer how the planet's atmosphere evolved over time.
The MAVEN mission has four primary scientific objectives:
- Determine the role that loss of volatiles to space from the Martian atmosphere has played through time.
- Determine the current state of the upper atmosphere, ionosphere, and interactions with the solar wind.
- Determine the current rates of escape of neutral gases and ions to space and the processes controlling them.
- Determine the ratios of stable isotopes in the Martian atmosphere.[
The blue panel shows hydrogen gas extending away from the surface, while the green one depicts oxygen remaining closer to the surface. These two elements are important because they come from the breakdown of water and carbon dioxide in Mars' atmosphere, as well as match what his team thought they would see, said Nick Schneider, who leads the Imaging Ultraviolet Spectrograph science team at the University of Colorado. According to Schneider:
"The fact that the images matched our simulation means that it exceeded our expectations,"
This news is very encouraging and leads those of us who are Mars junkies to anticipate a ringing success for the rest of MAVEN's one year (planned) exploits.