Galaxies NGC 4085 & NGC 4088 (Arp 18)
History
William Herschel discovered NGC 4088 on 9 March 1788 and recorded it as I 206 with the notes: «Considerably bright, extended, 45° north preceding south following, 6' long, 4' broad, almost equally bright.» [464] On 12 April 1789 he discovered the galaxy NGC 4085 which he recorded as I 224 with the notes: «Considerably bright, pretty large, much extended, small nucleus.» [465]
In Halton Arp's 1966 «Atlas of Peculiar Galaxies», the galaxy NGC 4088 is listed as Arp 18, a spiral galaxy with detached segments. He noted: «End of one spiral arm partially disconnected.» [199]
Physical Properties
| Name | RA | Dec | Type | bMag | vMag | B-V | SB | Dim | PA | z | D(z) | MD | Dreyer Description | Identification, Remarks |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| NGC 4085 | 12 05 22.4 | +50 21 12 | Gx (SBc) | 13.0 | 12.4 | 0.6 | 13.1 | 2.8 × 0.8 | 78 | 0.002487 | 10.50 | 18.960 | B, pL, pmE 78°, vsbM | WH I 224; GC 2707=2705; UGC 7075; MCG 9-20-86; CGCG 269-32; IRAS 12028+5037 |
| NGC 4088 | 12 05 34.6 | +50 32 26 | Gx (SBbc) | 11.2 | 10.6 | 0.6 | 13.2 | 5.6 × 2.1 | 43 | 0.002524 | 10.66 | 16.240 | B, cL, E 55°, lbM | WH I 206; GC 2708; UGC 7081; MCG 9-20-89; CGCG 269-33; Arp 18; VV 357; IRAS 12030+5049 |
Finder Chart
The two galaxies are located in the constellation Ursa Maior. On 21 March, the galaxy pair is in opposition to the Sun and crosses the meridian at midnight local time. The best time to observe it is during the months of November to July.
