2018.A.2.4. Mars Aerosol Tracker (MAT): An Areostationary SmallSat to Monitor the Martian Weather

Author(s)

Luca Montabone (1,2)
Michael VanWoerkom (3)
Bruce Cantor (4)
Michael J. Wolff (1)
Michael D. Smith (5)
Michel Capderou (2)
François Forget (2)

Space Science Institute, United States of America
Laboratoire de Météorologie Dynamique – IPSL, France
ExoTerra Resource LLC, United States of America
Malin Space Science Systems, Inc., United States of America
NASA Goddard Space Flight Center, United States of America

Session

A.2

Keywords

Mars, Weather, Aerosol, Dust storms, Areostationary orbit, SmallSat

Abstract

Thanks to NASA funding (PSDS3 program), we have elaborated a mission concept to put a SmallSat in an equatorial, circular, planet-synchronous (i.e. areostationary) orbit around Mars at 17,031.5 km altitude for at least one Martian year. This concept targets the atmosphere of Mars and its weather, in the form of dust storms and water ice clouds. We will address key scientific questions: What are the processes controlling the dynamics of dust and water ice aerosols, and promoting the evolution of regional dust storms into global dust events? The primary scientific objectives are: 1) to monitor a large, fixed portion of the planet where dust storms and water ice clouds are likely to occur, using visible and infrared wavelengths with high sampling rate; 2) to observe the temporal evolution of dust storms and water ice clouds in the monitored area throughout the diurnal cycle; 3) to detect changes in surface physical properties (e.g. thermal inertia and albedo) throughout the diurnal cycle, and particularly after the occurrence and decay of large dust storms. Our industrial partner, ExoTerra Resource LLC, adapted its Electrically Propelled Interplanetary CubeSat bus as part of the mission design. Based on the results of our concept study, the spacecraft is a low-cost, low-weight, small-size, ESPA-class system capable of supporting various tank sizes in order to provide a wide range of ΔV for three different Mars arrival scenarios as well as science mapping and communication from areostationary orbit. The SmallSat will carry an imaging system consisting of three fixed-focus camera heads: one 5.0-megapixel visible color camera, and two 0.3-megapixel thermal infrared cameras, each with its own narrow-angle lens. The cameras will provide full-disk images of Mars -up to 80° away from nadir- with resolutions of 4 km (visible) and 16 km (infrared), at high sampling frequency. The set of two infrared detectors is responsive over the wavelength range 7.9 μm – 16 μm, divided in six bandpasses. We will produce co-located and simultaneous 1) high-resolution visible images of dust storms and water ice clouds during daytime, 2) maps of infrared column aerosol optical depth and temperature (at several altitude levels below 45 km), sampled at multiple times a day. Our SmallSat will greatly increase the temporal resolution and coverage of single events, due to its unique areostationary orbit. The mission concept bypasses the current limitation of orbiters at Mars, which do not provide continuous and simultaneous observations over fixed, large regions.