NGC 691 Galaxy Group
History
The galaxies NGC 678, NGC 680 and NGC 697 were discovered on 15 September 1784 by the German-British astronomer William Herschel with his 18.7 inch reflecting telescope. He did not come across NGC 691 until 13 November 1786. The discovery of NGC 694 by the German astronomer Heinrich d'Arrest did not take place until 2 December 1861. He used an 11 inch refractor telescope. IC 167 was discovered on 4 January 1889 by the French astronomer Guillaume Bigourdan with a 12.4 inch refractor. The tail light of this discovery round is IC 1730 which was discovered on 17 January 1896 by the French astronomer Stephane Javelle with the 76 cm refractor telescope of the Observatoire de Nice. [196, 277]
Physical Properties
These galaxies belong to the NGC 691 galaxy group, which is located approximately at a distance of 27.8 Mpc to 40.9 Mpc from us. Some sources also include NGC 695 in this group, but their distance is about 135 Mpc, which means it is far in the background. [145]
| Name | RA | Dec | Type | bMag | vMag | B-V | SB | Dim | PA | z | D(z) | MD | Dreyer Description | Identification, Remarks |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| NGC 678 | 01 49 24.8 | +21 59 49 | Gx (SBb) | 13.3 | 12.2 | 1.1 | 13.4 | 4.5 × 0.8 | 78 | 0.009457 | 39.95 | 27.050 | pB, S, iR, mbM, p of 2 | WH II 228; GC 399; UGC 1280; MCG 4-5-14; CGCG 482-18; A 0147+21 |
| NGC 680 | 01 49 47.3 | +21 58 16 | Gx (E1) | 12.9 | 11.9 | 1.0 | 13.1 | 1.8 × 1.6 | 156 | 0.009340 | 39.45 | 33.680 | pB, S, iR, mbM, f of 2 | WH II 229; GC 402; UGC 1286; MCG 4-5-15; CGCG 482-19 |
| NGC 691 | 01 50 41.7 | +21 45 37 | Gx (Sbc) | 12.2 | 11.4 | 0.8 | 13.7 | 3.4 × 2.5 | 95 | 0.008889 | 37.55 | 36.000 | F, cL, vglbM | WH II 617; GC 410; UGC 1305; MCG 4-5-19; CGCG 482-23; CGCG 460-31; IRAS 01479+2130 |
| NGC 694 | 01 50 58.4 | +21 59 49 | Gx (S0/P) | 14.3 | 13.7 | 0.6 | 16.1 | 0.6 × 0.4 | 160 | 0.009840 | 41.56 | F, S, R, bet 2 st 15 | GC 413; UGC 1310; MCG 4-5-20; MK 363; IRAS 01481+2144; CGCG 482-24; 5ZW 122 | |
| NGC 697 | 01 51 17.5 | +22 21 27 | Gx (SBbc) | 12.8 | 12.0 | 0.8 | 13.9 | 4 × 1.3 | 105 | 0.010307 | 43.54 | 35.500 | F, cL, E, mbM | WH III 179; GC 416; NGC 674; UGC 1317; MCG 4-5-22; CGCG 482-27; IRAS 01485+2206 |
| IC 167 | 01 51 08.5 | +21 54 45 | Gx (SBc) | 13.6 | 13.1 | 0.5 | 14.8 | 2.7 × 1.8 | 95 | 0.009777 | 41.30 | 27.680 | eF, * 10.5 n 4' | UGC 1313; MCG 4-5-21; CGCG 482-25; Arp 31; IRAS 01483+2139 |
| IC 1730 | 01 49 57.9 | +22 00 46 | Gx (S0) | 15.4 | 14.4 | 1.0 | 13.3 | 0.8 × 0.5 | 65 | 0.009870 | 41.69 | F, S, R, gbM | MCG 4-5-15A; CGCG 482-20; NPM1G +21.0080 |
Finder Chart
The NGC 691 galaxy group can be found in the constellation Sternbild Aries. On 23 October it is in opposition to the Sun and crosses the meridian at local midnight. The best time to observe is July to April, when it is highest at night.
