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(IAAC) Obj: NGC 6397 - Inst: 70mm f/6.8 Pronto altaz refractor



Observer: Lew Gramer, Jim Cooper, Jeff Wilson
Your skills: Intermediate (some years)
Date/time of observation: 22:10 Local, 12/13 Aug 2001
Location of site: Long Key FL USA (Lat 25N, Elev 1m)
Site classification: Rural
Sky darkness: 7.5 <Limiting magnitude> [6.8 near object]
Seeing: 8 <1-10 Seeing Scale (10 best)>
Moon presence: None - moon not in sky
Instrument: 70mm f/6.8 Pronto altaz refractor
Magnification: 15x, 36x
Filter(s): None.
Object(s): NGC 6397
Category: Globular cluster.
Class: IX
Constellation: ARA
Data: mag 5.3 10.0m*; size 25.7'
Position: 174041 -534024
Description:
This fine little example of a "deep-southern" Globular
is, in fact, one of the very NEAREST globular clusters
to the Earth, and so despite its IX classification it
shows a fine tight core of many bright stars, most of
them well-resolved even at lower power. (Resolution at
the very core seems to be quite sensitive to very good
seeing, so logging a complete resolution may, in fact,
be challenging at other Northern Hemisphere locations?)
It is a strange feeling to see what LOOKS like a tight
(class III-IV) glob, and yet to resolve it in a Pronto.
--
Besides that detail however, (and ignoring the abstract
fact that it MAY be Earth's CLOSEST globular!) NGC 6397
is otherwise a pretty, but not unusual North Summer GC.
What an amazing contrast n6397 provides with the OTHER
bright GC in Ara just to the other side of Alpha Arae,
however! NGC 6352 (see the preceding IAAC log), by way
of comparison, is among the more distant known clusters
associated with the Milky Way, and what's stranger, it
sometimes seems to be classified as BOTH an open and a
globular cluster: even cursory observation shows why...
[Note my observation time change to 10pm on both logs!]
--
My thanks to Jim Cooper and his magisterial observing
lists (and his encyclopedic memory), for pointing out
to me both of these fine, contrasting clusters in Ara.
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