NGC 718
Galaxy in the constellation Pisces
From Wikipedia, the free encyclopedia
NGC 718 is a intermediate spiral galaxy in the constellation of Pisces. Its velocity with respect to the cosmic microwave background is 1,450±22 km/s, which corresponds to a Hubble distance of 69.7 ± 5.0 Mly (21.38 ± 1.54 Mpc).[1] Additionally, one non-redshift measurement gives a similar distance of 69.80 Mly (21.400 Mpc).[2] It was discovered by German-British astronomer William Herschel on 13 December 1784.[3][4]
| NGC 718 | |
|---|---|
NGC 718 imaged by SDSS | |
| Observation data (J2000 epoch) | |
| Constellation | Pisces |
| Right ascension | 01h 53m 13.2826s[1] |
| Declination | +04° 11′ 44.805″[1] |
| Redshift | 0.005781±0.0000300[1] |
| Heliocentric radial velocity | 1,733±9 km/s[1] |
| Distance | 69.7 ± 5.0 Mly (21.38 ± 1.54 Mpc)[1] |
| Group or cluster | NGC 676 group |
| Apparent magnitude (V) | 12.59[1] |
| Characteristics | |
| Type | SAB(s)a[1] |
| Size | ~99,000 ly (30.35 kpc) (estimated)[1] |
| Apparent size (V) | 2.3′ × 2.0′[1] |
| Other designations | |
| IRAS 01506+0357, 2MASX J01531331+0411453, UGC 1356, MCG +01-05-041, PGC 6993, CGCG 412-039[1] | |
NGC 718 has a possible active galactic nucleus, i.e. it has a compact region at the center of a galaxy that emits a significant amount of energy across the electromagnetic spectrum, with characteristics indicating that this luminosity is not produced by the stars.[5][6]
A star-forming disk has been detected around the core of NGC 718. The size of its semi-major axis is estimated at 1,100 ly (330 pc).[7]
Supermassive black hole
Based on measurements of the near-infrared K-band luminosity of the galaxy's bulge, NGC 718 has a supermassive black hole with a mass of 1×107.5M☉ (32 million solar masses).[8]
NGC 676 group
Intermediate-luminosity red transient
One intermediate-luminosity red transient (ILRT) has been observed in NGC 718:
- AT 2019udc (Type ILRT, mag. 18.813) was discovered by the Distance Less Than 40 Mpc Survey (DLT40) on 4 November 2019.[10] This object had initially been classified as a luminous blue variable.[11][12]
