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Old January 24th 12, 09:31 AM posted to alt.binaries.pictures.astro
Rick Johnson[_2_]
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Default ASTRO: NGC 6229 The "other" Hercules globular cluster

NGC 6229 is the "other" globular in Hercules. M13 and M92 get all the
attention while poor NGC 6992 tends to be the wall flower. It isn't big
and bright like the other two are. Not because it isn't a major
globular cluster but because it is about 100,000 light-years away on the
outskirts of the galactic halo. Put it in close like M92 and M13 and it
would be a grand sight. Discovered by William Herschel in 1787 he
cataloged it as a planetary nebula being unable to resolve it into
stars. In 1819 Admiral Smyth reports someone recorded it as a comet.
This distant guy got no respect it seems.

While my field contains hundreds of galaxies only 3 and one quasar have
redshift data. Since I used 5 minute subs rather than 10 minute subs
and only 40 minutes of them, same as I normally do with 10 minute subs,
this one doesn't go as deep as normal. I chose to use 5 minute subs for
the L channel because that prevented the core from being saturated. By
using 5 minute subs I could better resolve the core. To compensate for
more read noise I need to take about an hour's worth of data. I forgot
about this when taking the image. Still you can faintly see the quasar
at 12 billion light-years light travel time. Since the color filters
block a lot of light I could use my normal 10 minute color subs.

14" LX200R @ f/10, L=8x5' RGB=2x10'x3, STL-11000XM, Paramount ME

Rick
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