[meteorite-list] NASA's Mars Reconnaissance Orbiter Studies Comet Flyby

[Ron Baalke]

http://www.jpl.nasa.gov/news/news.php?feature=4344

NASA's Mars Reconnaissance Orbiter Studies Comet Flyby
Jet Propulsion Laboratory
October 19, 2014

Mars Reconnaissance Orbiter Mission Status Report

NASA's Mars Reconnaissance Orbiter, which has sent home more data about 
Mars than all other missions combined, is also now providing data about 
a comet that buzzed The Red Planet today (Oct. 19).

The orbiter continues operating in good health after sheltering behind 
Mars during the half hour when high-velocity dust particles from comet 
C/2013 A1 Siding Spring had the most chance of reaching the paths of Mars 
orbiters. It maintained radio communications with Earth throughout the 
comet's closest approach, at 11:27 a.m. PDT (2:27 p.m. EDT), and the peak 
dust-risk period centered about 100 minutes later.

"The spacecraft performed flawlessly throughout the comet flyby," said 
Mars Reconnaissance Orbiter Project Manager Dan Johnston of NASA's Jet 
Propulsion Laboratory, Pasadena, California. "It maneuvered for the planned 
observations of the comet and emerged unscathed."

Following the critical period of dust flux, the orbiter is communicating 
at 1.5 megabits per second with NASA's Deep Space Network. It remained 
on Side A of its two redundant computers, and all subsystems are working 
as expected.

Downlink of data has begun from today's comet observations by three instruments 
on Mars Reconnaissance Orbiter. The full downlink may take days. These 
instruments -- the High Resolution Imaging Science Experiment (HiRISE), 
the Compact Imaging Spectrometer for Mars (CRISM), and the Context Camera 
(CTX) -- also observed the comet for days before the flyby and will continue 
to make observations of it in the next few days. The orbiter's other three 
instruments are being used to study possible effects of gas and dust in 
the comet's tail interacting with the atmosphere of Mars. These are the 
Mars Climate Sounder (MCS), the Mars Color Imager (MARCI) and the Mars 
Shallow Radar (SHARAD).

Three NASA Mars orbiters, two Mars rovers and other assets on Earth and 
in space are studying comet Siding Spring. This comet is making its first 
visit this close to the sun from the outer solar system's Oort Cloud, 
so the concerted campaign of observations may yield fresh clues to our 
solar system's earliest days more than 4 billion years ago.

Following the comet flyby, operators of NASA's Mars Atmosphere and Volatile 
EvolutioN (MAVEN) orbiter are assessing the status of that orbiter and 
operators for NASA's Mars Odyssey are anticipating resumption of communications.

The Mars Reconnaissance Orbiter mission met all its science goals for 
the two-year primary science phase ending in 2008. The spacecraft's overtime 
work since then has added to the science returns. The mission has provided 
more than 240 trillion bits of data about Mars, a volume equivalent to 
three-and-a-half months of nonstop, high-definition video. The data it 
acquired during the comet's closest approach to Mars are now being transmitted 
to Earth, but it will take many hours before downlink is complete and 
processing can start.

Objectives of the observing program are to attempt to image the comet 
nucleus, to study its surrounding coma of dust and gas, and to search 
for signatures of that material interacting with the Mars atmosphere. 
Observations of the comet will continue for another day or so, as the 
comet and Mars separate, with the comet reaching its closest approach 
to the sun in about a week, on Oct. 25.

JPL, a division of the California Institute of Technology, Pasadena, manages 
the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, 
Washington. Lockheed Martin Space Systems, Denver, built the spacecraft 
and supports its operations. Lead organizations for the orbiters' six 
science instruments are University of Arizona, Tucson, for HiRISE; Johns 
Hopkins University Applied Physics Laboratory, Laurel, Maryland, for CRISM; 
Malin Space Science Systems, San Diego, for CTX and MARCI; Sapienza University 
of Rome, Italy, for SHARAD; and JPL for MCS.

For more about the Mars Reconnaissance Orbiter mission, visit:

http://mars.jpl.nasa.gov/mro/

For more about comet C/2013 A1 Siding Spring, visit:

http://mars.nasa.gov/comets/sidingspring

Media Contact
Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278
guy.webster at jpl.nasa.gov

Dwayne Brown
NASA Headquarters, Washington
202-358-1726
dwayne.c.brown at nasa.gov