Galaxy pair NGC 4485/4490 in Canes Venatici

This is an interacting pair of galaxies, known as Arp 269 or VV 30 (nicknamed “Cocoon Galaxy”).

It should be visible with an aperture of 8 inch. However, the peculiar structures need a much larger telescope.

Most interesting is the difference in size and elongation. The angular distance of the galaxies is 3.5'.

The pair was discovered by William Herschel on 14 January 1788 with his 18.7-inch reflector at Slough and catalogued as I 197/98

Data                  NGC 4485                              NGC 4490

Position (2000):      12 30 31.3 +41 42 03 (CVn)            12 30 36.1 +41 38 43 (CVn)

Vmag:                 11.9                                  9.8

Surface brightness:   13.2                                  12.9

Size / PA             2.4' x 1.8' / 15°                     6.4' x 3.2' / 125°

Type:                 IBm pec                               SBcd

Distance:             34 Mill. ly                           34 Mill. ly

Other designation:    UGC 7648, Arp 269, VV 30              UGC 7651, Arp 269, VV30

[Image from NOAO]

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Planetary Nebula NGC 6765 in Lyra

Standing in the shadow of the famous M 57, this interesting small planetary nebula is often missed.

It was discovered by the German Albert Marth on 28 June 1864, observing with Lassell’s 48-inch reflector on Malta.

Though NGC 6765 is almost visible in an 8-inch telescope, the structure of the tiny, cigar shaped nebula needs an aperture of 14-inch.

An OIII filter is helpful.

Data                  NGC 6765

Position (2000):      19 11 06.5 +30 32 47 (Lyr)

Vmag:                 12.9

Central star:         16.0

Size                  40"

Type:                 IBm pec

Distance:             34 Mill. ly

Other designations:   PK 62+9.1, M 1-68, VV 221, ARO 185

[Image: Stefan Binnewies, Capella Observatory]