eROSITA All-Sky Survey (First 6 Months) Three-Band (2.3-5.0 keV) Source Catalog

The eROSITA telescope array aboard the Spektrum Roentgen Gamma (SRG) satellite began surveying the sky in December 2019, with the aim of producing all-sky X-ray source lists and sky maps of an unprecedented depth. The authors present catalogs of both point-like and extended sources using the data acquired in the first six months of survey operations (eRASS1; completed June 2020) over the half sky whose proprietary data rights lie with the German eROSITA Consortium. This catalog contains all X-ray sources detected in the 2.3-5 keV band with detection likelihood > 12. The 5466 sources detected in the less sensitive but harder 2.3-5 keV band is the result of the first true imaging survey of the entire sky above 2 keV. The eRASS1 main catalog, <a href="/W3Browse/erosita/erass1main.html">eRASS1MAIN</a>, contains nearly 930000 entries detected in the most sensitive 0.2-2.3 keV energy range and the sources (only the strongly associated ones) from the main catalog have been linked to eRASS1MAIN in this catalog. The reference paper presents methods to identify and flag potential spurious sources in the catalogs, which were applied for this work, and the authors tested and validated the astrometric accuracy via cross-comparison with other X-ray and multi-wavelength catalogs. The catalogs form part of the first data release (DR1) of the SRG/eROSITA all-sky survey. Beyond the X-ray catalogs, DR1 contains all detected and calibrated event files, source products (light curves and spectra), and all-sky maps. The data files are linked to the table and also accessible from the <a href="/docs/srg/erosita/">HEASARC eROSITA</a> and <a href="https://erosita.mpe.mpg.de/dr1/">eROSITA-DE ERASS1</a> websites. The catalog uses the following designation for indicating the bands for the different measurement: <pre> Band Energy range (keV) 0 0.2 - 5.0 1 0.2 - 0.6 2 0.6 - 2.3 3 2.3 - 5.0 </pre> This database table was ingested by the HEASARC in June 2024 and is based upon the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/682/A34">CDS Catalog J/A+A/682/A34</a> file erass1-h.dat. In some cases, the HEASARC has altered the original field names, as per HEASARC conventions, and provides the original field names in square brackets. This is a service provided by NASA HEASARC .

Data and Resources

Additional Info

Field Value
Maintainer HEASARC Help Desk
Last Updated June 8, 2026, 15:46 (UTC)
Created April 1, 2025, 13:15 (UTC)
accessLevel public
bureauCode {026:00}
catalog_conformsTo https://project-open-data.cio.gov/v1.1/schema
harvest_object_id 2f51db55-14b7-404d-b908-8ee4a39895c4
harvest_source_id b99e41c6-fe79-4c19-bbc3-9b6c8111bfac
harvest_source_title Science Discovery Engine
identifier ivo://nasa.heasarc/erass1hard
landingPage ivo://nasa.heasarc/erass1hard
license https://www.usa.gov/government-works
modified 2026-06-03T16:52:47Z
programCode {026:000}
publisher High Energy Astrophysics Science Archive Research Center
resource-type Dataset
source_datajson_identifier true
source_hash a7d7636ba9ce5634357d73f38d75c630ecdfbd7e003b32704cf2212e1c62f332
source_schema_version 1.1
theme {Astrophysics}