NGC 5866 (M102 ?)

Lenticular (S0) Galaxy NGC 5866 (M102 ?), type S0_3,

Spindle Galaxy

This galaxy is situated in the northern constellation

Draco at RA 15h 06.5, Dec +55d 46′ (2000.0). It is the brightest of a

remarkable group of galaxies (the NGC 5866 group), lying roughly

40 million light-years distant (R. Brent Tully’s Nearby Galaxies Catalog

has the slightly larger value of about 50 million light-years), which also

contains the big bright edge-on spiral

NGC 5907 (type Sb+, 10.4 mag vis), the

fainter galaxy NGC 5879 (Sb, 11.5), and more very faint galaxies

(NGCs 5866B (= UGC 9769), 5862, 5905, 5908 and IC 1099; NGC 5866A (Turn 121A)

is a faint background galaxy within the field of this group).

From the dynamics of that group, E.M. and G.R. Burbidge (ApJ 131, p. 224-226,

1960) have estimated NGC 5866’s mass to be about 1 trillion solar masses, so

it is a considerably massive galaxy. The 5.2′ diameter of NGC 5866

correspondes to about 60,000 light-years, its globular cluster halo extends

more far outward.

No supernovae have been discovered in this galaxy yet.

NGC 5866 is possibly M102, i.e. it is plausible that

Pierre Mechain had found and described this object (but he later

disclaimed). Moreover, there is some evidence that Charles Messier may have

observed this object when measuring the position he added to entry No. 102

in his personal copy, but this subject is still somewhat dubious and therefore

If it should be true that neither Mechain nor Messier have observed

NGC 5866, it was probably first seen by William Herschel (or perhaps by

Caroline Herschel) in the mid or late 1780s; it bears Herschel’s number

H I.215 (Admiral Smyth writes it was discovered in March, 1789).

Our image of NGC 5866 was provided by

Stephan Korth. It was taken

by Bernd Koch and Stefan Korth,

on 12 March 1995 at 1:09 UT with a Celestron 14 at f=4.060mm, located at the

Sternwarte Aufderh&ouml.he near Solingen, Germany.

The camera was a Starlight XPress, exposure time 5m 28s.

Image processing was done with PIXWIN and Corel PhotoPaint by the authors.