Performance overview and science goals of the
Cosmic Origins Spectrograph for the Hubble Space Telescope

Jon A. Morse^a, James C. Green^a, Dennis Ebbets^b, John Andrews^a, Sara R. Heap^c,
Claus Leitherer^d, Jeffrey Linsky^e, Blair D. Savage^f, J. Michael Shull^a, Theodore P. Snow^a,
S. Alan Stern^g, Oswald Siegmund^h, John T. Stocke^a, Erik Wilkinson^a, Ken Brownsberger^a
Steve Penton^a, Stephane Beland^a, and Steve Osterman<sup>a

a</sup> University of Colorado, Center for Astrophysics and Space Astronomy,
Campus Box 389, Boulder, CO 80309 USA
^b Ball Aerospace & Technologies Corporation,
1600 Commerce Street, P.O. Box 1062, Boulder, CO 80306-1062 USA
^c NASA/Goddard Space Flight Center, Code 681, Greenbelt, MD 20771 USA
^d Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 USA
^eUniversity of Colorado, JILA, Campus Box 440, Boulder, CO 80309 USA
^f University of Wisconsin, Astronomy Department,
475 N. Charter Street, Madison, WI 53706 USA
^g Southwest Research Institute, 1050 Walnut Street, #429,
Boulder, CO 80302 USA
^h University of California, Space Sciences Laboratory, Berkeley, CA 94720

Abstract:

We present an overview of the expected performance and science goals of the Cosmic Origins Spectrograph (COS), a fourth generation instrument to be installed aboard the Hubble Space Telescope during the final HST servicing mission now scheduled for early 2004. COS is an ultraviolet spectrograph optimized for observing faint point sources with moderate spectral resolution (R $\\geq 20,000$). The instrument has two channels: a Far-Ultraviolet channel that is sensitive in the 1150 - 1775 Å wavelength range and a Near-Ultraviolet channel that operates between 1700 - 3200 Å. The COS Science Team program concentrates on QSO absorption line systems and the IGM, dynamics of the ISM in galaxies and galaxy halos, UV extinction in the Milky Way, and volatile gases in the atmospheres of Solar System bodies.