sci25009 — Announcement

The new European James Webb Space Telescope (eJWST) Science Archive

17 December 2025

-By Chris Evans, María Arévalo Sánchez, Deborah Baines, Javier Espinosa Aranda, Victor Fernández Rubio, Monica Fernández Barreiro, Alvaro Labiano Ortega, Marcos López-Caniego Alcarria, Bruno Merín Martin, Paule Sonnentrucker-

The European James Webb Space Telescope (eJWST) Science Archive is hosted at ESA’s European Space Astronomy Centre (ESAC). Building on the decades-long partnership between NASA and ESA on Hubble, and now together with the CSA, the eJWST archive provides a European mirror of all public Webb data in the Mikulski Archive for Space Telescopes (MAST) archive at the Space Telescope Science Institute.

We are delighted to announce the release of a new version of eJWST. To allow for effective and intuitive exploration of Webb data, and to ensure a consistent look and feel between the mission archives, the new version features a similar interface as the European Hubble Space Telescope (eHST) archive. The new eJWST includes a one-line search functionality on the home page for quick queries, as well as advanced search filters. ESASky is fully integrated in the results table, enabling effective cross-matching with data and catalogues from ESA’s missions and data products from a wide range of other astronomical facilities. Quick previews are available for each image file in the results table, as well as an interactive image viewer for more detailed inspection, that is also available from the high-level eJWST menu.

The latest eJWST also includes a first subset of High Level Science Products (HLSPs) for Webb. These are final science products provided by science teams to MAST for wider use by the community. Typical HLSPs from Webb programmes include reduced image mosaics, spectra, datacubes, and source catalogues. To enable seamless access to these science-enabling products, three first HLSP collections have been added to eJWST, and others will be included in the coming year. In brief, the initial three collections are:

• JEMS: JWST Extragalactic Medium-band Survey (PIs: Williams, Tacchella, Maseda). A deep Cycle 1 NIRCam and NIRISS imaging programme using five medium-band filters (F182M, F210M, F430M, F460M, F480M) at 2 and 4 microns in the GOODS-South field. It includes two NIRCam footprints (using all five filters) and one NIRISS footprint (with the F430M and F480M filters). One of the NIRCam footprints covers the full extent of the Hubble Ultra Deep Field (HUDF), building on the deepest multi-wavelength public datasets available anywhere on the sky.
  
  
• WIDE: The NIRSpec WIDE GTO Survey (PI: Maseda). Obtained as part of the NIRSpec Guaranteed Time Observations (GTO), WIDE consists of 31 pointings in the five CANDELS extragalactic fields with exquisite ancillary Hubble Space Telescope photometry. Each pointing uses NIRSpec’s MicroShutter Array (MSA) to simultaneously obtain spectra for an average of 135 galaxies each. Observations were obtained with the low-resolution PRISM and the high-resolution G235H and G395H gratings. The pointing centres were selected to maximise the observability of the rarest sources.
  
  
• GOALS: The Great Observatories All-sky LIRG Survey – JWST (PIs: Armus, Evans). The GOALS sample comprises over 200 of the most luminous infrared-selected galaxies in the local Universe. As part of one of the Early Release Science (ERS) programmes, four of the GOALS galaxies were observed with NIRSpec, NIRCam and MIRI. The GOALS HLSPs feature MIRI Medium Resolution Spectrometer (MRS) datacubes for the nuclear regions of two galaxies: NGC 7469 and VV 114.

We encourage you to explore these latest features, and to provide us with your feedback via the eJWST Helpdesk.