[meteorite-list] Rosetta's Comet: Imaging the Coma

[Ron Baalke]

http://www.jpl.nasa.gov/news/news.php?release=2014-256  

Rosetta's Comet: Imaging the Coma
Jet Propulsion Laboratory
July 31, 2014

Less than a week before Rosetta's rendezvous with comet
67P/Churyumov-Gerasimenko, images obtained by OSIRIS, the spacecraft's
onboard scientific imaging system, show clear signs of a coma
surrounding the comet's nucleus.

A new image from July 25, 2014, clearly reveals an extended coma
shrouding 67P's nucleus. "Our coma images cover an area of 150 by 150
square kilometers (90 by 90 square miles)," said Luisa Lara from the
Institute of Astrophysics in Andalusia, Spain. Most likely these images
show only the inner part of the coma, where particle densities are
highest. Scientist expect that 67P's full coma actually reaches much
farther.

In the current image, the hazy, bright, circular structure to the right
of the comet's nucleus is an artifact of the OSIRIS optical system. The
center of the image located around the position of the nucleus is
overexposed here.

Other new images of the comet's nucleus confirm the collar-like
appearance of the neck region, which appears brighter than most parts of
the comet's body and head. Possible explanations range from differences
in material or grain size to topological effects.

Rosetta is a European Space Agency mission with contributions from its
member states and NASA.

The scientific imaging system, OSIRIS, was built by a consortium led by
the Max Planck Institute for Solar System Research (Germany) in
collaboration with Center of Studies and Activities for Space,
University of Padua (Italy), the Astrophysical Laboratory of Marseille
(France), the Institute of Astrophysics of Andalusia, CSIC (Spain), the
Scientific Support Office of the European Space Agency (Netherlands),
the National Institute for Aerospace Technology (Spain), the Technical
University of Madrid (Spain), the Department of Physics and Astronomy of
Uppsala University (Sweden) and the Institute of Computer and Network
Engineering of the TU Braunschweig (Germany). OSIRIS was financially
supported by the national funding agencies of Germany (DLR), France
(CNES), Italy (ASI), Spain, and Sweden and the ESA Technical Directorate.

Rosetta's Philae lander is provided by a consortium led by DLR, Max
Planck Institute for Solar System Research, CNES and ASI. Rosetta will
be the first mission in history to rendezvous with a comet, escort it as
it orbits the sun, and deploy a lander to its surface.

NASA's Jet Propulsion Laboratory, Pasadena, California, a division of
the California Institute of Technology, also in Pasadena, manages the
U.S. participation in the Rosetta mission for NASA's Science Mission
Directorate in Washington. Rosetta carries three NASA instruments in its
21-instrument payload.

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

Preston Dyches Jet Propulsion Laboratory, Pasadena, Calif. 818-354-7013
preston.dyches at jpl.nasa.gov Dwayne Brown NASA Headquarters 202-358-1726
dwayne.c.brown at nasa.gov Markus Bauer
European Space Agency, Noordwijk, Netherlands
011-31-71-565-6799
markus.bauer at esa.int

Birgit Krummheuer
Max Planck Institute for Solar System Research
011-49-551-384-979-462
krummheuer at mps.mpg.de

2014-256