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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.


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, similar to the data available in the Mikulski Archive is also available in the HSLA. These data are packaged into "smart archives" according to target type and scientific themes to facilitate the construction of archival samples for common science uses. A new "quick look" capability makes the data easy for users to access and download. Coadded COS/NUV data and STIS UV spectra will be made available in future releases.


April 2017

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 have been re-calibrated and re-coadded. For COS/FUV, the most important change is the use of the new COS FUV dispersion solutions, for Lifetime Position 1 and Lifetime Position 2. Data obtained at Lifetime Position 3 still use the old dispersion solutions.

For more information on the new wavelength solutions, see the articles linked here:
COS/FUV LP2 updates:
COS/FUV LP1 updates:

This release also contains the COS/NUV data for all targets that have FUV data as well as for targets that only have NUV data. These data have been calibrated with the most up-to-date dispersion solutions:
The COS/NUV data included in this release are only the individual *x1dsum* files produced by the COS pipeline, i.e., only data obtained with the same cenwave within a given visit are coadded. The full coadded COS/NUV data will be included in a future release.

IMPORTANT NOTE: 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. In particular, this release of the Legacy database was timed to inform proposers in preparation for the Cycle 25 call for proposals.

Data Access

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

Do you want the entire thing? It's only 25 GB.


Description of the first release can be found here: ISR2017_04.pdf.
Initial project description can be found here: 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.

Questions and Comments

We invite questions and comments about the database to