The GLASS HST data

September 2 2015: The GLASS survey paper describing the first public data release is now available!

The GLASS survey paper:
The GLASS inspection software:
The GLASS data products:


The GLASS data consist of 140 orbits of HST grism spectroscopy in the G102, G141 and G800LP grism and direct images in F105W, F140W and F814W of the 10 massive galaxy clusters:

  • Abell 370 (FF)
  • Abell 2744 (FF)
  • MACS0416.1-2403 (FF, CLASH)
  • MACS0717.5+3745 (FF, CLASH)
  • MACS0744.9+3927 (CLASH)
  • MACS1149.6+2223 (FF, CLASH)
  • MACS1423.8+2404 (CLASH)
  • MACS2129.4-0741 (CLASH)
  • RXC J2248.7-4431; [Abell S1063] (FF, CLASH)
  • RXC J1347.5-1145 (CLASH)

(FF refers to a Hubble Frontier Fields cluster and CLASH refers to a Cluster Lensing And Supernova survey with Hubble cluster)

The total exposure time per cluster is approximately 10 orbits in G102, 4 in G141 (both on the cluster core), and 2×7 orbits in F814W+G800L (in the parallel cluster infall regions). Each cluster is observed at two orientations, differing by approximately 90 degrees, in order to facilitate de-blending and extraction of the spectra.

GLASS Data Products

The GLASS collaboration will publish value-added catalogs and reduction products for each of the cluster following the release schedule for the GLASS data products presented in Treu et al. (2015) {}

  • A370 – Winter 2016
  • A2744 – Fall 2015
  • MACS0416.1-2403 – Winter 2016
  • MACS0717.5+3745 – Treu et al. (2015), ApJ, 812:114
  • MACS0744.9+3927 – Winter 2016
  • MACS1149.6+2223 – Fall 2015
  • MACS1423.8+2404 – Summer 2015
  • MACS2129.4-0741 – Summer 2015
  • RXJ1347.5-1145 – Summer 2015
  • RXJ2248 – Summer 2015

All products will be made available the Mikulski Archive for Space Telescopes (MAST) server at
The raw data is available through MAST as well:

GLASS Software

As part of the first public data release presented in Treu et al. (2015) the GLASS collaboration has released a set of graphical user interfaces – the GLASS inspections GUI (GiG) and the GLASS inspection GUI for redshifts (GiGz) – which provide a convenient and efficient way to inspect and browse the GLASS data products. Both GiG and GiGz are available at:

GLASS acknowledgement

If you find the data products or software of the GLASS collaboration described above and available at helpful, please cite