22MHz ivo://nasa.heasarc/skyview/22mhz NASA/GSFC HEASARC DRAO, MPI for Radio Astronomie Skyview Project 2026-10-02 SkyView Help Skyview at skyview.gsfc.nasa.gov surveys Roger et al. (1999) presented a map of the 22 MHz radio emission between declinations -28° and +80°, covering ~73% of the sky, derived from observations with the 22 MHz radiotelescope of the Dominion Radio Astrophysical Observatory (DRAO). The resolution of the telescope (EW x NS) is 1.2° x 1.7° secant(zenith angle). Roger et al. emphasize that the main value of the data lies in the representation of structure larger than the beam. The strongest point sources (Cas A, Cyg A, Tau A and Vir A) have been removed from the map. <p> The Centre d'Analyse de Données Etendues group used the data to form an all-sky HEALPix format map following the method described in Appendix A of Paradis et al. 2012, A&A, 543, 103, ADS. Their HEALPix map is mirrored here. The map is in units of K brightness temperature. Map pixels are set to a sentinel value of -32768.0 for unobserved regions and for regions affected by sidelobes around Cyg A, Tau A, and Vir A. Provenance: DRAO, MPI for Radio Astronomie. This is a service of NASA HEASARC. https://skyview.gsfc.nasa.gov Archive Research service-for HEASARC https://skyview.gsfc.nasa.gov/cgi-bin/vo/sia.pl?survey=22mhz& GET text/xml+votable POS Search Position in the form "ra,dec" where ra and dec are given in decimal degrees in the ICRS coordinate system. degrees real SIZE Size of search region in the RA and Dec. directions. degrees real FORMAT Requested format of images. string CFRAME Coordinate frame: ICRS, FK5, FK4, GAL, ECL string EQUINOX Equinox used in FK4 or FK5 frames. real Cutout 360.0 180.0 360.0 180.0 5000 10000000 500 0 0 10 10 https://skyview.gsfc.nasa.gov/cgi-bin/query.pl Radio