Harold Corwin

NGC 3565 and NGC 3566. These two objects were given the same poor position by Ormond Stone in the first Leander McCormick list. The identification with the close pair of galaxies listed in the table was made by noting that many of the first list nebulae were placed about two minutes of time too far west. Subtracting two minutes from the RA puts the position very close to the faint pair.

The identification of this pair as NGC 3565 and 3566 is obviously not very secure because the discovery position is poor, and there are no sketches of the objects among Stone's papers.

Another possibility is that NGC 3565 and NGC 3566 are identical to IC 2623 and the star superposed just south. However, this would require a 4 minute error in Stone's RA, as well as a 4 minute declination error. While a few of the Leander McCormick positions are indeed this far off, I think that this possibility is less likely.

Still -- I've been bothered by the identification of the pair as Stone's objects because they are so close together, and because the optical and infrared sky surveys show an apparent nucleus BETWEEN the two components. This strongly suggests that there is but one peculiar galaxy here. Hence the question marks. I have to question, too -- if this is indeed Stone's pair -- whether he could see both objects.

― NGC 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