Comet 67P is Releasing More Water Into Space
Posted on January 24, 2015
NASA says comet 67P/Churyumov-Gerasimenko is releasing more water into space. The Rosetta mission's Philae lander touched down on the surface of the 4 kilometer-wide (2.5-mile-wide) comet last November. The amount of water vapor being released by the comet increased about tenfold from June 2014 to August 2014.
The observations were made using the NASA's Microwave Instrument for Rosetta Orbiter (MIRO). The MIRO is a small lightweight spectrometer that measure the temperature just below the surface of the comet. It can also map the abundance, temperature and velocity of water vapor released by the comet into space.
Sam Gulkis, principal investigator of the MIRO instrument at NASA's Jet Propulsion Laboratory in Pasadena, California, says in a statement, "In observations over a period of three months [June through August, 2014], the amount of water in vapor form that the comet was dumping into space grew about tenfold. To be up close and personal with a comet for an extended period of time has provided us with an unprecedented opportunity to see how comets transform from cold, icy bodies to active objects spewing out gas and dust as they get closer to the sun."
Astronomers also note that the comet's atmosphere (called come) is much less homogeneous than astronomers were expecting. The comet outgassing varies with spikes in water readings followed shortly by spikes in carbon dioxide readings.
Claudia Alexander, NASA project scientist for the U.S. Rosetta team, says in a statement, "Taken together, the MIRO outgassing results and results about heterogeneous fountains from ROSINA suggest fascinating new details to be learned about how comets work. These results are helping us move the field forward on how comets operate on a fundamental level."
Another recent release about 67P from the ESA says the comet is rich in organics. The release says macromolecular organic compounds cover the entire surface of the comet's nucleus.
The above image of comet 67P was taken by the Rosetta's NavCam on December 7, 2014. An animation of comet 67P created from images acquired by the Rosetta spacecraft can be found here.
