Cosmic Origins Spectrograph (COS): Science

Painting by Michael Carroll		COS Information Links
		COS Instrument and Science Overview
		Science Requirements Review -- Science Goals (Powerpoint)
		Center for Astrophysics and Space Astronomy (CASA)
		University of Colorado - Boulder (CU)
		Ball Aerospace & Technologies Corp.

Spectroscopy lies at the heart of astrophysical inference. Our understanding of the origin and evolution of the cosmos critically depends on our ability to make quantitative measurements of physical parameters such as the total mass, distribution, motions, temperatures, and composition of matter in the Universe. Detailed information on all of these properties can be gleaned from high-quality spectroscopic data. For distant objects, some of these properties (e.g., motions and composition) can only be measured through spectroscopy.

UV spectroscopy provides some of the most fundamental diagnostic data necessary for discerning the physical characteristics of planets, stars, galaxies, and interstellar and intergalactic matter. The UV offers access to spectral features that provide key diagnostic information that cannot be obtained at other wavelengths.

The Cosmic Origins Spectrograph (COS) will bring the diagnostic power of ultraviolet spectroscopy to bear on such fundamental issues as the ionization and baryon content of the intergalactic medium and the origin of large-scale structure in the Universe; the ages, dynamics, and chemical enrichment of galaxies; and stellar and planetary origins. COS will be, by a large factor, the most sensitive UV spectrograph ever flown aboard HST. COS will complement and extend the suite of HST instruments, ensuring that Hubble maintains a powerful UV spectroscopic capability from Servicing Mission 4 until the end of its mission.

See also the complementary UV instruments/missions: HST/STIS, FUSE, and GALEX.