About COS
The Cosmic Origins Spectrograph (COS) was installed on the Hubble Space Telescope (HST) in May 2009. COS performs high-sensitivity, medium- and low-resolution spectroscopy of astronomical objects in the 815-3200 Å wavelength range. COS significantly enhances the spectroscopic capabilities of HST at ultraviolet wavelengths, providing observers with unparalleled opportunities for observing faint sources of ultraviolet light.
The primary science objectives of the instrument are the study of the origins of large scale structure in the Universe, the formation and evolution of galaxies, the origin of stellar and planetary systems, and the cold interstellar medium.

This COS spectrum of a massive star in the LMC encodes information about the properties of its stellar wind, the intervening interstellar and circum-galactic media, enabling a wide range of legacy studies.
Current Status
COS/FUV is operating nominally.
COS/NUV is operating nominally.
Helpful Links
Program Information
COS Instrument Resources
Recent News
Recently Published Documents
Instrument Science Reports (ISRs)
Listing Results
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Showing 5 matching items
May 26, 2023D. Sahnow & C. Johnson
ISR 2023-11: Mitigation of the Fixed Pattern Noise on COS: Effective Signal-to-Noise versus Number of FP-POS Spectral Dithers
May 18, 2023J. Roman-Duval et al.
ISR 2023-10: LP5 Exploratory Study
May 18, 2023B. James et al.
ISR 2023-09: Creation of the LAMPTAB reference file for use at Lifetime Position 6
May 12, 2023N. Indriolo et al.
ISR 2023-08: The Spectral Resolution of the COS FUV Channel at Lifetime Position 5
April 21, 2023S. Dieterich et al.