A3 ivo://nasa.heasarc/a3 NASA/GSFC HEASARC Remillard 2026-04-10 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Observation This database table contains information from the HEAO 1 A3 MC LASS Catalog of X-ray Sources. The MC experiment contained two four-grid modulation collimators with an egg-crate collimator with an overall FOV of 4 x 4 degrees (FWHM). The objects in the catalog are possible HEAO 1 A1 sources. The HEAO 1 experiment began on day 224, 19 August 1977 and ended on day 739, 9 January 1979. This is a service provided by NASA HEASARC . https://heasarc.gsfc.nasa.gov/W3Browse/all/a3.html Archive Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=a3& GET text/xml 180 99999 true 226.195324063675 -83.0375606836458 1 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=a3 GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_a3&Action=More+Options&Action=Parameter+Search&ConeAdd=1 HEAO1 1 X-ray public a3 HEAO 1 A3 MC LASS Catalog "__row" System index column char nullable "__y_ra_dec" System unit vector column double nullable name Source Designation meta.id;meta.main char nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable dec Declination degree pos.eq.dec;meta.main double nullable type Type of Object src.class char nullable "__x_ra_dec" System unit vector column double nullable bii Galactic Longitude degree pos.galactic.lat double nullable class Browse Object Classification src.class short nullable "__z_ra_dec" System unit vector column double nullable lii Galactic Latitude degree pos.galactic.lon double nullable catalog_designation NRL 1H Catalog Source Designation meta.id char nullable