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Here we show some optical photographs of some of the designated UIT Targets together with some brief explanation of the proposed science.
M101
is the most actively star forming nearby galaxy. It has very high
surface brightness and has very large H II regions, particularly
at large distances from its center. Previous UV imaging shows that
the UV size of M101 is actually larger than its optical size,
indicating that low level star formation is occurring in the extreme
outer regions of M101.
Low Surface Brightness galaxies are objects with very low
contrast with respect to the night sky background. Many of these
galaxies have not been catalogued or discovered until very recently.
A recent analysis , in fact, suggests that most of the disk galaxies
in the nearby universe are in this population and thus have been missed
by most previous surveys. The three specific objectives of the UIT
campaign on Low Surface Brightness galaxy imaging are:
To meet these goals, the exposure times will be 2000 seconds. The longest exposure times which were obtained on the Astro I mission with UIT were around 600 seconds. Thus, in addition to gaining information on LSB galaxies, these observations will also constitute a deep Ultraviolet Survey over a fairly large field of view. We hope, if the Universe is cooperative, to be able to discover new objects in these deep fields.
NGC
1097 is a nearby barred spiral with some sites of very active
star formation. The galaxy also has some collimated jets of
emission coming from the nuclear regions.
NGC
5128 is a really whacked out galaxy. It is suspected to be the
result of a merger between galaxies and has an overall morphology
that looks like suspiciously like this
model merger remnant . UIT observations of NGC 5128 or
Centaurus A will be quite interesting.