HIPASS Detection of an Intergalactic Gas Cloud in the NGC 2442 Group
Abstract
We report the discovery from the H I Parkes All-Sky Survey (HIPASS) of a gas cloud associated with the asymmetric spiral galaxy NGC 2442. This object, designated HIPASS J0731-69, contains ~109 Msolar of H I, or nearly one-third as much atomic gas as NGC 2442 itself. No optical counterpart to any part of HIPASS J0731-69 has yet been identified, consistent with the gas being diffuse and its streamlike kinematics. If the gas in HIPASS J0731-69 was once part of NGC 2442, then it was most likely a fairly recent tidal encounter with a moderately massive companion that tore it loose, although the possibility of ram-pressure stripping cannot be ruled out. This discovery highlights the potential of the HIPASS data for yielding new clues to the nature of some of the best-known galaxies in the local universe.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 2001
- DOI:
- 10.1086/321453
- arXiv:
- arXiv:astro-ph/0103099
- Bibcode:
- 2001ApJ...555..232R
- Keywords:
-
- galaxies: individual (NGC 2442);
- Galaxies: Interactions;
- galaxies: intergalactic medium;
- Radio Lines: Galaxies;
- Astrophysics
- E-Print:
- 8 pages, 4 figures, uses "emulateapj5.sty". Accepted for publication in ApJ, Vol. 555, 1 July 2001. Figs 1 and 2 included as JPEG