Harold Corwin

Yann Pothier suggested in August 2016 that this object, found by Lewis Swift on 11 May 1890, may be UGC 06726 = CGCG 243-002 rather than the considerably fainter CGCG 243-003 that we have assumed up to now. The errors would be +52 seconds in RA and -9.2 arcminutes in Dec rather than +43 seconds in RA alone. All of these are close enough to digit errors (+50 seconds, -10 arcminutes, and +40 seconds) that a choice on that criterion alone would suggest the "traditional" identification with the fainter galaxy -- just one error rather than two.

However, Yann points out that the magnitudes tell a different story. UGC 6726 is nearly two magnitudes brighter, V = 13.8 vs. 15.6 for CGCG 243-003 (magnitudes converted from SDSS photometry). This is a pretty convincing argument, so I have put colons on the UGC object, and question marks on the fainter CGCG.

Another possibility that Yann mentions is NGC 3870. For this, the RA error is only +4 seconds, and the Dec error is -38 arcminutes, suggestive of a 40 arcminute digit error. The galaxy is even brighter, too, at V = 13.1.

So, there are three reasonable choices for Swift's object. My own feeling is that UGC 6726 is the correct object, but given that the other two galaxies have points in their favor, I don't think that we can rule them out.

― IC Notes by Harold Corwin

Drawings, descriptions, and CCD photos are copyright Andrew Cooper unless otherwise noted, no usage without permission.

A complete list of credits and sources can be found on the about page