A New View of the Moon

KAMUELA, HI—On Oct. 9, astronomers at the W. M. Keck Observatory used the Keck II telescope to search for water harbored in the Moon’s permanently shadowed craters.

The observations were made as part of the Observatory’s participation in NASA’s Lunar Crater Observation and Sensing Satellite, or LCROSS, mission. At 1:31 and 1:35 a.m. Hawaii Standard Time, two LCROSS impactors collided with the crater Cabeus on the South Pole of the Moon.

Diane Wooden of the NASA Ames Research Center in Moffett Field, Calif. used Keck II with its Near Infrared Echelle Spectrograph, or NIRSPEC, to analyze the resulting ejecta plume for the chemical signature of water vapor.

It is the first time that astronomers could use features on the Moon’s surface to properly position the Keck II telescope to take spectroscopic observations and images of the lunar surface. NIRSPEC’s upgraded guide camera and improved guiding software, which are part of the Observatory’s program called MAGIQ, or Multi-function Acquisition, Guiding, and Image Quality, monitoring system, made the spectroscopic observations possible and took the images.

Wooden and the other LCROSS astronomers are currently evaluating the spectroscopic data collected at Keck and the other Mauna Kea observatories for the water vapor signature. The team plans to report the results soon.

The W. M. Keck Observatory operates two 10-meter optical/infrared telescopes on the summit of Mauna Kea on the island of Hawai’i. The twin telescopes feature a suite of advanced instrumentation including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectroscopy and a world-leading laser guide star adaptive optics system. The Observatory is a scientific partnership of the California Institute of Technology, the University of California and NASA. For more information please call 808.881.3827 or visit http://www.keckobservatory.org.