General Tools    Coordinate Converter    Date Converter    Energy Converter    nH    X-ray Background    TIPTOPbase    Source Finder    Bibliography    FITS File Verifier Multi-Mission Tools    RPS    Timeline Tool    Viewing    WebPIMMS    WebSpec    xTime Mission Tools    HEXTErock    RXTE Weather Map

NH       Calculate the Total Galactic H I Column Density (Powered by HEAsoft) Object Name or Coordinates: (e.g., Cyg X-1 or 101.295, -16.699 or 6 45 10.8, -16 41 58) Name Resolver: NED only SIMBAD only GRB only GRB, NED, then SIMBAD GRB, SIMBAD, then NED Coordinate System: Equatorial FK5 Equatorial FK4 Galactic Ecliptic Equinox:    (Only applies to Equatorial coordinates.) Cone Radius: degrees Map: Leiden/Argentine/Bonn (LAB) Dicky & Lockman (DL) Both      R.A. and Dec. can be entered in ddd.ddd/[s]dd.ddd or hh mm ss.s/[s]dd mm ss.s . References: Kalberla et al. 2005, Astronomy & Astrophysics, 440, 775 (LAB Map). References: Dickey & Lockman, 1990, ARAA, 28, 215 (DL Map). nH is a Web version of the nH FTOOL, which was developed by Lorella Angelini at the HEASARC. The Web interface is maintained by Edward J. Sabol of the HEASARC. Note: An alternative tool to calculate the neutral hydrogen column density out to a specified distance within our galaxy is available at the MAST web site. This tool was originally created and hosted by the now-closed Center for Extreme-Ultraviolet Astrophysics (CEA). HEASARC Home | Observatories | Archive | Calibration | Software | Tools | Students/Teachers/Public

Science Mission Directorate Universe Division Beyond Einstein | Origins FAQ/Comments/Feedback Education Resources Find helper applications like Adobe Acrobat A service of the Astrophysics Science Division at NASA/ GSFC and the High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory (SAO) HEASARC Director: Dr. Alan P. Smale HEASARC Associate Director: Dr. Roger Brissenden Responsible NASA Official: Phil Newman Web Curator: Meredith Gibb Privacy Policy and Important Notices.