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    • RASS X-Ray Variable Sources Catalog

    Metadata Updated: March 13, 2026

    The RASS X-Ray Variable Sources Catalog contains the results of a systematic search for variability among the ROSAT All-Sky Survey (RASS) X-ray sources. Lightcurves were generated for about 30,000 X-ray point sources which were detected sufficiently high above the background. For the variability study different search algorithms were developed in order to recognize flares, periods and trends, respectively. The variable X-ray sources were optically identified with counterparts in the SIMBAD, the USNO-A2.0 and NED data bases, but a significant part of the X-ray sources remain without cataloged optical counterparts. A complete list of the 1207 X-ray variable sources that were found is presented in this table. This table was created by the HEASARC in July 2003 based on CDS table J/A+A/403/247/table7.dat. This is a service provided by NASA HEASARC .

    Access & Use Information

    Public: This dataset is intended for public access and use. License: See this page for license information.

    Downloads & Resources

    Dates

    Metadata Created Date April 11, 2025
    Metadata Updated Date March 13, 2026

    Metadata Source

    Harvested from NASA Data.json

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Created Date April 11, 2025
    Metadata Updated Date March 13, 2026
    Publisher High Energy Astrophysics Science Archive Research Center
    Maintainer
    Identifier ivo://nasa.heasarc/rassvars
    Data Last Modified 2026-03-09
    Category Astrophysics
    Public Access Level public
    Bureau Code 026:00
    Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
    Schema Version https://project-open-data.cio.gov/v1.1/schema
    Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
    Harvest Object Id dcb4365d-7484-4a72-9acd-ef1ecff12771
    Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
    Harvest Source Title NASA Data.json
    Homepage URL ivo://nasa.heasarc/rassvars
    License https://www.usa.gov/government-works
    Program Code 026:000
    Source Datajson Identifier True
    Source Hash e085d3d7461aab464cde5509bbb28068f76681ed07c2169ea31f787db4a5dab7
    Source Schema Version 1.1

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