LECTURES:: Keck Institute for Space Studies

Co-Sponsored NASA GALEX Mission

GALEX Complete the Sky Survey (GCSS):
A Fundamental Milky Way Legacy Dataset

Start Date: April 1, 2012
California Institute of Technology
Pasadena, CA 91125

We are exploiting the first 9‐12 months in 2012 to complete the newly accessible Milky Way Galactic Plane. We call this the GALEX Complete the Sky Survey (GCSS). NASA planned to close the GALEX mission at the end of December, 2011. A large portion of the Galactic Plane, which we have only recently begun to survey, will have no data. NASA, recognizing the scientific value of the Galactic Plane survey, encouraged the project to seek outside funding for completing the Survey. The Keck Institute for Space Studies was the first organization to provide partial funding for this important project.

The GALEX Complete the Sky Survey will complete the Galactic Plane survey, areas shown in white (see figure above).

While GALEX has been optimized for extragalactic observations, our coverage of the Milky Way Galactic Plane has been limited by countrate limits set to protect the life of the Near UV photon‐counting detector at 100 kcps. We have increased those limits to 1 Mcps—the resulting data quality is still very high and comparable to lower countrate observations. By
raising the limits, and in some cases imposing no limits, we are now in a position to fill in the Galactic Plane and the remaining unobserved parts of the Magellenic Clouds that have exceeded the 1 Mcps limits.

For questions contact: Chris Martin