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Welcome to the HST Spectroscopic Legacy Archive (HSLA).

Coadd spectrum of NGC 5548, composed of 764 coadded exposures.
Time-series spectra of NGC 5548 showing variability.
Coadd spectrum of HS 1700+6416.
Coadd spectrum of WD 2218+706.
Coadd spectrum of SN 1987A.
Coadd spectrum of FAIRALL 9.
Coadd spectrum of MRK-54.
Coadd spectrum of TW Hya.
Coadd spectrum of V4046 SGR.
Time-series spectra of WD 0308-565.


With no future space ultraviolet instruments currently planned, the data from the UV spectrographs aboard the Hubble Space Telescope have a legacy value beyond their initial science goals. This release of the Hubble Spectroscopic Legacy Archive (HSLA) provides to the community new combined spectra for COS far-ultraviolet (FUV) data publicly available as of February 2016. COS/NUV data and STIS UV spectra will be made available in future releases. These data are packaged into "smart archives" according to target type and scientific themes to facilitate the contructions of archival samples for common science uses. A new "quick look" capability make the data easy for users to quickly access and download.

This early 2017 release includes more than 200 new targets and recent public data on targets included in last year's releases. All the data has been re-calibratied and re-coadded. The most important change is the new COS dispersion solutions, which have been applied to all data. For more information on this new wavelength solution, see the articles linked here:
COS/FUV updates:
COS/NUV updates:

IMPORTANT NOTE: This release of the Legacy database is intended to inform Cycle 25 AR and GO proposals. The content and format of the data are designed to enable users to assess the quantity and quality of data that already exists in the archive to support their science goals. Programs that are accepted and proceed to a full analysis should be sure to use the latest releases posted here. Other modes and instruments will follow over time.

Questions and Comments

We invite questions and comments about the database to

Data Access

Pre-Sorted Target Tables - Targets sorted by target type. Access to exposures and coadds, all the diagnostic plots, and cross-matched information from Simbad or NED.

Want the entire thing? It's only 25 GB.


Project description and documentation is available in this PDF.

The HST Spectral Legacy makes use of Spectator, written by Molly Peeples, to create its plots of demographics and spectra. Spectator is open-source python, and is available on GitHub.