[meteorite-list] NASA Instrument Aboard Rosetta Spacecraft Returns First Science Results

[Ron Baalke]

September 4, 2014
     
NASA Instrument aboard European Spacecraft Returns First Science Results

A NASA instrument aboard the European Space Agency's (ESA's) Rosetta 
orbiter has successfully made its first delivery of science data from comet 
67P/Churyumov-Gerasimenko.

The instrument, named Alice, began mapping the comet's surface last month, 
recording the first far-ultraviolet light spectra of the comet's surface. 
 From the data, the Alice team discovered the comet is unusually dark -- 
darker than charcoal-black -- when viewed in ultraviolet wavelengths. Alice 
also detected both hydrogen and oxygen in the comet's coma, or atmosphere.

Rosetta scientists also discovered the comet's surface so far shows no 
large water-ice patches. The team expected to see ice patches on the 
comet's surface because it is too far away for the sun's warmth to turn 
its water into vapor.

"We're a bit surprised at just how unreflective the comet's surface is 
and how little evidence of exposed water-ice it shows," said Alan Stern, 
Alice principal investigator at the Southwest Research Institute in Boulder, 
Colorado.

Alice is probing the origin, composition and workings of comet 
67P/Churyumov-Gerasimenko, to gather sensitive, high-resolution insights that 
cannot be obtained by either ground-based or Earth-orbiting observation. It 
has more than 1,000 times the data-gathering capability of instruments flown 
a generation ago, yet it weighs less than nine pounds (four kilograms) and 
draws just four watts of power. The instrument is one of two full instruments 
on board Rosetta that are funded by NASA. The agency also provided portions 
of two other instrument suites.

Other U.S. contributions aboard the spacecraft are the Microwave Instrument 
for Rosetta Orbiter (MIRO), the Ion and Electron Sensor (IES), part of the 
Rosetta Plasma Consortium Suite, and the Double Focusing Mass Spectrometer 
(DFMS) electronics package for the Rosetta Orbiter Spectrometer for Ion 
Neutral Analysis (ROSINA). They are part of a suite of 11 total science 
instruments aboard Rosetta.

MIRO is designed to provide data on how gas and dust leave the surface of the 
nucleus to form the coma and tail that gives comets their intrinsic beauty. 
IES is part of a suite of five instruments to analyze the plasma environment 
of the comet, particularly the coma.

To obtain the orbital velocity necessary to reach its comet target, the 
Rosetta spacecraft took advantage of four gravity assists (three from Earth, 
one from Mars) and an almost three-year period of deep space hibernation, 
waking up in January 2014 in time to prepare for its rendezvous with 
67P/Churyumov-Gerasimenko.

Rosetta also carries a lander, Philae, which will drop to the comet's 
surface in November 2014.

The comet observations will help scientists learn more about the origin and 
evolution of our solar system and the role comets may have played in 
providing Earth with water, and perhaps even life.

Rosetta is an ESA mission with contributions from its member states and NASA. 
Rosetta's Philae lander is provided by a consortium led by the German 
Aerospace Center in Cologne; Max Planck Institute for Solar System Research 
in Göttingen; French National Space Agency in Paris; and the Italian Space 
Agency in Rome.

NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, manages the 
U.S. contribution to the Rosetta mission for the agency's Science Mission 
Directorate in Washington. JPL also built the MIRO instrument and hosts its 
principal investigator, Samuel Gulkis. The Southwest Research Institute, 
located in San Antonio and Boulder, developed Rosetta's IES and Alice 
instruments and hosts their principal investigators, James Burch (IES) and 
Alan Stern (Alice).

For more information on the U.S. instruments aboard Rosetta, visit:

http://rosetta.jpl.nasa.gov 

More information about Rosetta is available at:

http://www.esa.int/rosetta 

-end-

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

DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011
agle at jpl.nasa.gov 

Maria Martinez
Southwest Research Institute, Boulder, Colo.
210-522-3305
mmartinez at swri.org 

Markus Bauer
European Space Agency, Noordwijk, Netherlands
011-31-71-565-6799
markus.bauer at esa.int