Astronomy and Astrophysics – Astronomy
Scientific paper
Sep 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006dps....38.7302t&link_type=abstract
American Astronomical Society, DPS meeting #38, #73.02
Astronomy and Astrophysics
Astronomy
Scientific paper
Before MRO's arrival at Mars, during Mars Express orbits 17 to 2888, SPICAM obtained 617 stellar occultation measurements of density and temperature structure from 40km to 140km. SPICAM measurements give global atmospheric structure over an entire Martian year. Where SPICAM derived atmospheric profiles overlap MRO aerobraking altitudes from 100km to 140km, we have made interannual comparisons with in situ MRO accelerometer derived atmospheric profiles for matching season, local solar time, latitude, longitude and altitude.
Designed for aerobraking, MRO launched August 12, 2005, and achieved Mars Orbital Insertion (MOI) March 10, 2006. Atmospheric density decreases exponentially with increasing height. Using small propulsive changes to apoapsis orbital velocity, periapsis altitude was adjusted to the necessary density surfaces for safe aerobraking. MRO periapsis precessed from the South Pole at 6pm LST to near the equator at 3am LST. Meanwhile, apoapsis dramatically shrank from 40,000km at MOI to 460 km at aerobraking completion (ABX) mid-September 2006. Then, a few small propulsive maneuvers established the Primary Science Orbit (PSO), which without aerobraking would have required an additional 400 kg of fuel.
Honeywell's substantially improved electronics package for its IMU (QA-2000 accelerometer, gyro, electronics) maximized accelerometer sensitivities as requested by The George Washington University, JPL, and Lockheed Martin, enabling good signal-to-noise-ratios up to at least 170km, critical for upper atmospheric science. Each of the 500+ MRO aerobraking orbits provides a distribution of density, scale-height, and temperature along the orbital path, providing key in situ insight into various upper atmosphere (> 100 km) processes.
Characterization of key temporal and spatial cycles including: polar vortices, winter polar warming, dust storms, planetary scale waves, gravity waves, and gravitational tides associated with topography, validates and constrains both upper atmospheric circulation models used to understand the nature of high-altitude variability and transport processes, and engineering models used to plan future missions
Bertaux J. J.
Blanchard R.
Bougher Stephen
Forget Francois
Keating Garrett
No associations
LandOfFree
Interannual Comparison of Temporal and Spatial Structure in the Martian Thermosphere from Atmospheric Accelerometer Measurements of Mars Reconnaissance Orbiter (MRO) during Aerobraking and Stellar Occultation Measurements from the SPICAM Ultraviolet Infrar does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Interannual Comparison of Temporal and Spatial Structure in the Martian Thermosphere from Atmospheric Accelerometer Measurements of Mars Reconnaissance Orbiter (MRO) during Aerobraking and Stellar Occultation Measurements from the SPICAM Ultraviolet Infrar, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Interannual Comparison of Temporal and Spatial Structure in the Martian Thermosphere from Atmospheric Accelerometer Measurements of Mars Reconnaissance Orbiter (MRO) during Aerobraking and Stellar Occultation Measurements from the SPICAM Ultraviolet Infrar will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1078213