DR2 provides public access to the eROSITA-DE X-ray source catalogues derived from the cumulative observations obtained during the first three eROSITA All-Sky Surveys (eRASS:3). The release also includes upper-limit products and the accompanying documentation describing the catalogues and their contents.

Unlike DR1, DR2 is a catalogue-only release. It does not include calibrated event lists, images, exposure maps, background maps, sensitivity maps, source spectra, or light curves.

DR1 was based on the first six months of the eROSITA All-Sky Survey (eRASS1) and included both source catalogues and calibrated survey data products. DR2 is based on cumulative observations from the first three all-sky surveys (eRASS:3) and provides only source catalogues.

eRASS:3 refers to the cumulative dataset obtained during the first three complete scans of the sky by eROSITA. Combining these observations increases the effective exposure across the sky, improving source detection sensitivity and the precision of measured source properties.

DR2 contains sources detected in the Western Galactic hemisphere, corresponding to the region of the sky assigned to the German eROSITA Consortium (eROSITA-DE) with Galactic longitudes 359.94423568 > l >179.94423568 degrees.

The scientific exploitation of the eROSITA All-Sky Survey is shared equally between the German and Russian eROSITA consortia. To ensure a balanced distribution of Galactic and extragalactic science targets, the survey sky is divided into two Galactic hemispheres, with the Western hemisphere (Galactic longitudes 359.94423568 > l >179.94423568 degrees) assigned to eROSITA-DE.

No. The Cal-PV observations are not part of DR2. These data were released previously as part of the eROSITA Early Data Release (EDR).

The catalogues can be downloaded from the Source Catalogues page, which also provides detailed descriptions of the available products and download options.

The catalogues provide source positions, detection parameters, fluxes in multiple energy bands, extent information where applicable, and other measured source properties. A complete description of all catalogue columns is available in the catalogue documentation on the Source Catalogues page.

Upper-limit products provide flux upper limits at user-specified sky positions where no statistically significant X-ray source is detected. They are particularly useful for non-detections, variability studies, and multiwavelength analyses.

The DR1 event files, images, maps, and source catalogues remain available through the eROSITA-DE Data (eRODat) portal.

The Calibration and Performance Verification (Cal-PV) observations released as part of the Early Data Release remain available through the EDR webpages.

If you use the DR2 catalogues in a scientific publication, please acknowledge the eROSITA-DE DR2 release and cite the relevant reference papers listed on the Citation page.

If you cannot find the answer in this FAQ or the documentation, please visit the eROSITA-DE Help Forum, where members of the collaboration and the wider community can answer questions and discuss the data products.

Information on joining the eROSITA-DE collaboration as an external collaborator is available on the External Collaborators page, together with a list of the Working Group Chairs.