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Download the TRDS Spectral Atlas files via MAST HLSP.

HST Standard Stars Atlases

Two independent directories contain the spectra of ultraviolet and optical standard stars. CALOBS directory contains original as well as updated versions of the ultraviolet (IUE and VOYAGER2) and optical (Oke, Tapia or Stone) spectra of the standard stars. CALSPEC directory contains the composite ultraviolet and optical absolute calibrated reference spectra of the HST standards. We use these reference spectra to calibrate the HST instruments and should also be useful for the absolute calibration of ground-based or satellite data. We also have a set of supplemental CALSPEC data; which is available and detailed on the CALSPEC page.

Stellar Spectral Atlases

Spectral Atlases of Galaxies and Emission Line Objects

Other Spectra


HST Help Desk 

Please contact the HST Help Desk with any questions.