Neutral hydrogen gas (HI) is abundant in most
galaxies, but it is also found well outside their stellar envelopes where it
contributes to the intergalactic medium. Prominent nearby examples of
intergalactic gas include the Magellanic Stream and extended HI bridges in
the M 81 group of galaxies. The HI distribution towards the peculiar spiral
galaxy NGC 3263 (shown above) reveals a spectacular HI cloud about 175 x 100
kpc in size with an HI mass of ~109 Msun. For a full description
see the paper by
English, Koribalski et al. 2010. - We are currently writing
a review paper on "HI tidal tails, bridges and clouds".
