Lecturer: Joseph Grebowsky (NASA) Date: 2016-02-11 10:00 Place: Aulan
MAVEN (Mars Atmosphere and Volatile EvolutioN) Spacecraft Exploration of How Mars Lost its Atmosphere and Water
Joseph Grebowsky
MAVEN Project Scientist
NASA Goddard Space Flight Center
The Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft went into orbit around Mars on 21 September 2014. After a commissioning phase that included science observations of Mars and an exciting encounter with Comet Siding Spring during its close approach, its primary science phase began on 16 November 2014 and has been in orbit for more than a year. MAVEN’s scientific importance derives from definitive evidence that the early Mars atmosphere was very different from today’s – it was thick enough to allow stable liquid water to be present. MAVEN is addressing the questions of where did the water go and where did the CO2 go? Loss to space is indicated as being the key loss process, based on observations of escaping atoms at present, fractionated light stable isotopes most consistent with loss having been important, and the apparent absence of a sufficiently large surface/subsurface reservoir for CO2.
The science objectives of the MAVEN mission are: 1. For the first time, and comprehensively characterize the upper atmosphere and ionospheric of Mars; 2. Determine how these regions are controlled by the Sun’s radiation and solar wind; and 3. Expanding upon the path-finding escape-science observations by ESA’s Mars Express Mission, explore ALL the processes that drive the loss of gas from Mars to outer space. The overall goal is to understand the chain of processes leading to escape today, learn how to extrapolate back in time, and determine the integrated escape of atmosphere over Martian history.
This talk will describe evidence for the evolution of Mars atmosphere over time, the design and philosophy behind the MAVEN mission, and will highlight some exciting scientific observations from the first year of the mission.
Created 2016-01-13 22:53:44 by Mats Holmström Last changed 2016-02-05 15:40:47 by Mats Holmström
