NGC/IC Project Restoration Effort
(This is a very very beta version)
NGC3382
Basic Information
Location and Magnitude
Right Ascension: 10:48:25.5
Declination: +36:43:32
Constellation: LMI
Visual Magnitude:
Historic Information
Discoverer: Parsons L.
Year of discovery: 1874
Discovery aperture: 72.0
Observational
Summary description: F, S, iR, ? S Cl
Sub-type: *2
Corwin's Notes
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NGC 3382 is probably just two stars, if it is indeed anything on the sky. It
was found by Ralph Copeland (or perhaps the fourth Earl of Rosse) on 5 April
1874, who provided this description: "About 4 min p [NGC 3432]. pF, cL, R, bM,
*14 mag in centre. *9 Pos 238.0, Dist 173.7." There is no nebula within a
reasonably large field around the nominal position that matches that
description.
On 24 March 1878, Dreyer himself (or perhaps LdR) noted "4.0 min p and 6
arcmin +- n of [N3432]. vF, S, irr R, only a S group of sts. *9 Pos 192.0
deg, Dist 162.9 arcsec." This position is about an arcmin east-northeast of
two faint stars where there is nothing else to be seen. There is a 10th mag
star south-southwest of the widely-separated pair, but neither its distance
(about 166 arcsec) nor position angle (about 192 deg) from the pair closely
match Copeland's measurements. The agreement with Dreyer's lends some
credence to the identification with the two stars, so I am fairly comfortable
with them as Dreyer's object.
I've entered the mean position of the two stars in the main table, but it
seems more likely to me that Copeland misidentified his reference galaxy:
rather than being N3432, it is perhaps some other object.
There is a clue in the printed observation dates. There is no observation
recorded from Birr of NGC 3432 on 5 April 1874 (there is one, however, on 24
March 1878, apparently by Dreyer): How is it that Copeland refered his
observation of NGC 3382 to it if he did not observe it on the same date?
(Probably pretty easy to do; we should see if the original log books still
exist at Birr.) Other objects observed on 5 April 1874 include NGC 3182, NGC
3188, and Copeland's Septet (NGC 3745 et al.; see the story under NGC 3743).
However, none of these have galaxies -- or even stars -- at the offsets noted
by Copeland for N3382.
Let's look instead at the date on which NGC 3432 was first observed, 18 March
1876. Other objects from that night that might be the reference object for
N3382 are NGC 2718, NGC 2974, and NGC 4152.
Only NGC 2974 has a galaxy near the offset: CGCG 007-015 at 09 38 29.86,
-03 34 49.9 (J2000; 2MSP). The star, at 09 38 17.29 -03 35 48.6 (J2000, Ty2)
is at bit further than claimed -- 197 arcsec rather than 174 arcsec -- and at
a different PA -- 252 deg rather than 238 deg. Finally, there are two other
stars, nearly as bright as the one Copeland measured, and at about the same
distance from the galaxy, south-southeast and east-northeast. But the general
configuration is approximately what Copeland has recorded, so I've included
the galaxy as a distant possibility.