NGC 718

NGC 718
NGC 718
	NGC 718 imaged by SDSS
Observation data (J2000 epoch)
Constellation	Pisces
Right ascension	01h 53m 13.2826s
Declination	+04° 11′ 44.805″
Redshift	0.005781±0.0000300
Heliocentric radial velocity	1,733±9 km/s
Distance	69.7 ± 5.0 Mly (21.38 ± 1.54 Mpc)
Group or cluster	NGC 676 group
Apparent magnitude (V)	12.59
Characteristics
Type	SAB(s)a
Size	~99,000 ly (30.35 kpc) (estimated)
Apparent size (V)	2.3′ × 2.0′
Other designations
	IRAS 01506+0357, 2MASX J01531331+0411453, UGC 1356, MCG +01-05-041, PGC 6993, CGCG 412-039

Galaxy in the constellation Pisces

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 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 1×10^7.5M_☉ (32 million solar masses).^[8]

NGC 676 group

NGC 718 is a member of a small group of three galaxies known as the NGC 676 group. The other two galaxies are NGC 676 and NGC 693.^[9]

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]

References

^ a b c d e f g h i j k "Results for object NGC 0718". NASA/IPAC Extragalactic Database. NASA and Caltech. Retrieved 27 December 2025.
^ "Distance Results for NGC 0718". NASA/IPAC Extragalactic Database. NASA. Retrieved 27 December 2025.
^ Herschel, William (1786). "Catalogue of One Thousand New Nebulae and Clusters of Stars" (PDF). Philosophical Transactions of the Royal Society of London. 76: 457–499. Bibcode:1786RSPT...76..457H. doi:10.1098/rstl.1786.0027.
^ Seligman, Courtney. "New General Catalogue Objects: NGC 718". Celestial Atlas. Retrieved 27 December 2025.
^ Asmus, D.; Greenwell, C. L.; Gandhi, P.; Boorman, P. G.; Aird, J.; Alexander, D. M.; Assef, R. J.; Baldi, R. D.; Davies, R. I.; Hönig, S. F.; Ricci, C.; Rosario, D. J.; Salvato, M.; Shankar, F.; Stern, D. (2020). "Local AGN survey (LASr): I. Galaxy sample, infrared colour selection, and predictions for AGN within 100 MPC". Monthly Notices of the Royal Astronomical Society. 494 (2): 1784. arXiv:2003.05959. Bibcode:2020MNRAS.494.1784A. doi:10.1093/mnras/staa766.
^ "NGC 718". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 27 December 2025.
^ Comerón, S.; Knapen, J. H.; Beckman, J. E.; Laurikainen, E.; Salo, H.; Martínez-Valpuesta, I.; Buta, R. J. (2010). "AINUR: Atlas of Images of NUclear Rings". Monthly Notices of the Royal Astronomical Society. 402 (4): 2462. arXiv:0908.0272. Bibcode:2010MNRAS.402.2462C. doi:10.1111/j.1365-2966.2009.16057.x.
^ Dong, X. Y.; De Robertis, M. M. (2006). "Low-Luminosity Active Galaxies and Their Central Black Holes". The Astronomical Journal. 131 (3): 1236. arXiv:astro-ph/0510694. Bibcode:2006AJ....131.1236D. doi:10.1086/499334.
^ Mahtessian, A. P. (1998). "Groups of galaxies. III. Some empirical characteristics". Astrophysics. 41 (3): 308–321. Bibcode:1998Ap.....41..308M. doi:10.1007/BF03036100.
^ Valerin, G.; et al. (2025). "A study in scarlet: I. Photometric properties of a sample of intermediate-luminosity red transients". Astronomy and Astrophysics. 695. arXiv:2407.21671. Bibcode:2025A&A...695A..42V. doi:10.1051/0004-6361/202451733.
^ "AT 2019udc". Transient Name Server. IAU. Retrieved 27 December 2025.
^ Siebert, M. R.; Dimitriadis, G.; Kilpatrick, C. D.; Foley, R. J.; Nunez, R.; McKinnon, K.; Guhathakurta, P. (2019). "Spectroscopic Classification of AT2019udc with the Lick Shane telescope". The Astronomer's Telegram. 13263: 1. Bibcode:2019ATel13263....1S.

External links

Media related to NGC 718 at Wikimedia Commons
NGC 718 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images

[ned-1] ^ a b c d e f g h i j k "Results for object NGC 0718". NASA/IPAC Extragalactic Database. NASA and Caltech. Retrieved 27 December 2025.

[ned-distance-2] "Distance Results for NGC 0718". NASA/IPAC Extragalactic Database. NASA. Retrieved 27 December 2025.

[herschel-3] Herschel, William (1786). "Catalogue of One Thousand New Nebulae and Clusters of Stars" (PDF). Philosophical Transactions of the Royal Society of London. 76: 457–499. Bibcode:1786RSPT...76..457H. doi:10.1098/rstl.1786.0027.

[selig-4] Seligman, Courtney. "New General Catalogue Objects: NGC 718". Celestial Atlas. Retrieved 27 December 2025.

[AGN-5] Asmus, D.; Greenwell, C. L.; Gandhi, P.; Boorman, P. G.; Aird, J.; Alexander, D. M.; Assef, R. J.; Baldi, R. D.; Davies, R. I.; Hönig, S. F.; Ricci, C.; Rosario, D. J.; Salvato, M.; Shankar, F.; Stern, D. (2020). "Local AGN survey (LASr): I. Galaxy sample, infrared colour selection, and predictions for AGN within 100 MPC". Monthly Notices of the Royal Astronomical Society. 494 (2): 1784. arXiv:2003.05959. Bibcode:2020MNRAS.494.1784A. doi:10.1093/mnras/staa766.

[SIMBAD-6] "NGC 718". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 27 December 2025.

[disk-7] Comerón, S.; Knapen, J. H.; Beckman, J. E.; Laurikainen, E.; Salo, H.; Martínez-Valpuesta, I.; Buta, R. J. (2010). "AINUR: Atlas of Images of NUclear Rings". Monthly Notices of the Royal Astronomical Society. 402 (4): 2462. arXiv:0908.0272. Bibcode:2010MNRAS.402.2462C. doi:10.1111/j.1365-2966.2009.16057.x.

[sbh-8] Dong, X. Y.; De Robertis, M. M. (2006). "Low-Luminosity Active Galaxies and Their Central Black Holes". The Astronomical Journal. 131 (3): 1236. arXiv:astro-ph/0510694. Bibcode:2006AJ....131.1236D. doi:10.1086/499334.

[mahtessian-9] Mahtessian, A. P. (1998). "Groups of galaxies. III. Some empirical characteristics". Astrophysics. 41 (3): 308–321. Bibcode:1998Ap.....41..308M. doi:10.1007/BF03036100.

[ILRT-10] Valerin, G.; et al. (2025). "A study in scarlet: I. Photometric properties of a sample of intermediate-luminosity red transients". Astronomy and Astrophysics. 695. arXiv:2407.21671. Bibcode:2025A&A...695A..42V. doi:10.1051/0004-6361/202451733.

[TNS-2019udc-11] "AT 2019udc". Transient Name Server. IAU. Retrieved 27 December 2025.

[ATEL-13263-12] Siebert, M. R.; Dimitriadis, G.; Kilpatrick, C. D.; Foley, R. J.; Nunez, R.; McKinnon, K.; Guhathakurta, P. (2019). "Spectroscopic Classification of AT2019udc with the Lick Shane telescope". The Astronomer's Telegram. 13263: 1. Bibcode:2019ATel13263....1S.