This article is from the Space FAQ, by Jon Leech leech@cs.unc.edu and Mark Bradford tla@surly.org with numerous contributions by others.
Don't ask for images to be posted to the space/astro newsgroups. They're
clumsy to access, wasteful of net resources, and inappropriate in
discussion groups. Retrieve images on your own using FTP or Web clients.
The possible combinations of image formats and machines is forebodingly
large, and I won't attempt to cover common formats (GIF, etc.) here. To
read PDS and VICAR (and many other) formats on Unix systems running X,
use XV 3.00, available in
ftp://ftp.x.org/contrib/xv-3.00.tar.Z
The FAQ for the Usenet group alt.binaries.pictures discusses image
formats and how to get image viewing software. A copy of this document
is available from the Usenet FAQ archives in
ftp://rtfm.mit.edu/pub/usenet/
 
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