NGC 1427

NGC 1427
Hubble Space Telescope image of NGC 1427
Observation data (J2000 epoch)
ConstellationFornax
Right ascension03h 42m 19.4s[1]
Declination−35° 23′ 33″[1]
Redshift0.004630[1]
Heliocentric radial velocity1388 ± 3 km/s[1]
Distance71 ± 8 Mly (21.9 ± 2.4 Mpc)[2]
Group or clusterFornax Cluster
Apparent magnitude (V)11.8[1]
Absolute magnitude (V)−20.43[3]
Characteristics
TypeE5[1]
Mass7.9×1010 (Stellar mass)/9.4×1010 (Total Mass)[4] M☉
Size~109,200 ly (33.49 kpc) (estimated)[1]
Apparent size (V)3.6 x 2.5[1]
Notable featuresLow-luminosity elliptical galaxy
Other designations
ESO 358- G 052, MCG -06-09-021, FCC 276, PGC 13609[1]

NGC 1427 is a low-luminosity elliptical galaxy[5] located approximately 71 million light-years away from Earth.[2] It was discovered by John Frederick William Herschel on November 28, 1837.[6] It is a member of the Fornax Cluster.[7][8] The galaxy has a stellar mass of 7.9 × 1010 M☉, and a total mass of 9.4 × 1010 M☉.[4] However, the mass of the dark matter halo surrounding the galaxy is around 4.3 × 1012 M☉.[9]

Characteristics

NGC 1427 is the brightest elliptical galaxy on the eastern side of the Fornax cluster, and is thought to have been accreted into the gravtional potential well of the cluster core more than 8 billion years ago.[8] It is around 9 billion years old.[10]

In the galaxy, dust patches are observed,[11] with the central region being host to a nuclear stellar disk with an estimated diameter of 52 ly (16 pc).[12] NGC 1427 is surrounded by 71 observed planetary nebulae.[13]

The galaxy has a supermassive black hole with an estimated mass of 9.1 × 107 M☉.[14]

Globular clusters

NGC 1427 is surrounded by a population of around 470 globular clusters, however estimates suggest that number may be as high as 510. It has a biomedial distribution of one population of metal-rich red clusters and another population of metal-poor blue clusters. The blue globular clusters have an abundance ratio of [Fe/H] = -1.02 ± 0.2, greater than that of the globular clusters in the halo of the Milky Way, while the red globular clusters have an abundance ratio of [Fe/H] = -0.15 making them more metal rich than the globular clusters in the bulge of the Milky Way. This suggests that the red globular clusters have more similarities to the metal-rich globular clusters found in disk galaxies unlike in giant elliptical galaxies like M87. Therefore as the red globular clusters have a higher metallicity than the blue globular clusters, this suggests that red globular clusters are younger than the blue global clusters, possibly having formed from ether galaxy mergers or another local galactic processes.[5]

Galaxy mergers

Computer simulations and observations of the inner stellar halo of NGC 1427, by Zhu et al. suggest that the formation of the galaxy's stellar halo requires the merger of a massive satellite galaxy of around 1.5+1.6
−0.7×1010 M☉ with NGC 1427 which is about one-fourth of its current stellar mass.

Also, the stars in NGC 1427's stellar halo are younger than most stars in the bulge; with these stars being the youngest in the galaxy. The stellar age distribution of the hot inner stellar halo of NGC 1427 indicates that this merger occurred within the last 8 billion years. Based on current understanding of galaxy evolution, stars in the inner halo of NGC 1427 should have formed before the massive merger ended, either in a preexisting disk of NGC 1427 or in the satellite galaxy before and during the merger, because of the triggering of star formation.[8]

References

  1. ^ a b c d e f g h i "NASA/IPAC Extragalactic Database". Results for NGC 1427. Retrieved 2006-12-13.
  2. ^ a b Jensen, Joseph B.; Tonry, John L.; Barris, Brian J.; Thompson, Rodger I.; et al. (February 2003). "Measuring Distances and Probing the Unresolved Stellar Populations of Galaxies Using Infrared Surface Brightness Fluctuations". Astrophysical Journal. 583 (2): 712–726. arXiv:astro-ph/0210129. Bibcode:2003ApJ...583..712J. doi:10.1086/345430. S2CID 551714.
  3. ^ Capuzzo-Dolcetta, R.; Mastrobuono-Battisti, A. (November 2009). "Globular cluster system erosion in elliptical galaxies". Astronomy & Astrophysics. 507 (1): 183–193. arXiv:0904.0526. doi:10.1051/0004-6361/200912255. ISSN 0004-6361.
  4. ^ a b Amblard, A.; Riguccini, L.; Temi, P.; Im, S.; Fanelli, M.; Serra, P. (2014-03-01). "Star Formation Bimodality in Early-type Galaxies". The Astrophysical Journal. 783 (2): 135. arXiv:1309.5418. Bibcode:2014ApJ...783..135A. doi:10.1088/0004-637X/783/2/135. ISSN 0004-637X.
  5. ^ a b Forte, Juan C.; Geisler, Doug; Ostrov, Pablo G.; Piatti, Andrés E.; Gieren, Wolfgang (2001-04-01). "The Globular Cluster System of the Low-Luminosity Elliptical Galaxy NGC 1427". The Astronomical Journal. 121 (4): 1992–2002. Bibcode:2001AJ....121.1992F. doi:10.1086/319954. hdl:11336/22471. ISSN 0004-6256.
  6. ^ "New General Catalog Objects: NGC 1400 - 1449". cseligman.com. Retrieved 2024-07-08.
  7. ^ Ferguson, Henry C. (August 1989). "Population studies in groups and clusters of galaxies. II - A catalog of galaxies in the central 3.5 deg of the Fornax Cluster". The Astronomical Journal. 98: 367. Bibcode:1989AJ.....98..367F. doi:10.1086/115152.
  8. ^ a b c Zhu, Ling; Van De Ven, Glenn; Leaman, Ryan; Pillepich, Annalisa; Coccato, Lodovico; Ding, Yuchen; Falcón-Barroso, Jesús; Iodice, Enrichetta; Navarro, Ignacio Martin; Pinna, Francesca; Corsini, Enrico Maria; Gadotti, Dimitri A.; Fahrion, Katja; Lyubenova, Mariya; Mao, Shude; McDermid, Richard; Poci, Adriano; Sarzi, Marc; De Zeeuw, Tim (2022). "The Fornax3D project: Discovery of ancient massive merger events in the Fornax cluster galaxies NGC 1380 and NGC 1427". Astronomy & Astrophysics. 664: A115. arXiv:2203.15822. Bibcode:2022A&A...664A.115Z. doi:10.1051/0004-6361/202243109. S2CID 247793082.
  9. ^ Spitler, Lee R.; Forbes, Duncan A.; Strader, Jay; Brodie, Jean P.; Gallagher, Jay S. (2008-03-01). "The connection between globular cluster systems and their host galaxy and environment: a case study of the isolated elliptical NGC 821". Monthly Notices of the Royal Astronomical Society. 385 (1): 361–380. arXiv:0712.1382. Bibcode:2008MNRAS.385..361S. doi:10.1111/j.1365-2966.2007.12823.x. ISSN 0035-8711.
  10. ^ Lee, Sang-Yoon; Chung, Chul; Yoon, Suk-Jin (2019-01-01). "Nonlinear Color-Metallicity Relations of Globular Clusters. VIII. Reproducing Color Distributions of Individual Globular Cluster Systems in the Virgo and Fornax Galaxy Clusters". The Astrophysical Journal Supplement Series. 240 (1): 2. arXiv:1811.00018. Bibcode:2019ApJS..240....2L. doi:10.3847/1538-4365/aaecd4. ISSN 0067-0049.
  11. ^ Forbes, Duncan A.; Franx, Marijn; Illingworth, Garth D. (1995-05-01). "Ellipticals with Kinematically Distinct Cores: WFPC1 Imaging of Nearby Ellipticals". The Astronomical Journal. 109: 1988. Bibcode:1995AJ....109.1988F. doi:10.1086/117425. ISSN 0004-6256.
  12. ^ Ledo, H. R.; Sarzi, M.; Dotti, M.; Khochfar, S.; Morelli, L. (2010-09-01). "A census of nuclear stellar discs in early-type galaxies". Monthly Notices of the Royal Astronomical Society. 407 (2): 969–985. Bibcode:2010MNRAS.407..969L. doi:10.1111/j.1365-2966.2010.16990.x. hdl:2299/5422. ISSN 0035-8711.
  13. ^ Spriggs, T. W.; Sarzi, M.; Galán-de Anta, P. M.; Napiwotzki, R.; Viaene, S.; Nedelchev, B.; Coccato, L.; Corsini, E. M.; Fahrion, K.; Falcón-Barroso, J.; Gadotti, D. A.; Iodice, E.; Lyubenova, M.; Martín-Navarro, I.; McDermid, R. M. (2021-09-01). "The Fornax3D project: Planetary nebulae catalogue and independent distance measurements to Fornax cluster galaxies". Astronomy and Astrophysics. 653: A167. arXiv:2107.09680. Bibcode:2021A&A...653A.167S. doi:10.1051/0004-6361/202141314. ISSN 0004-6361.
  14. ^ Arzoumanian, Zaven; Baker, Paul T.; Brazier, Adam; Brook, Paul R.; Burke-Spolaor, Sarah; Becsy, Bence; Charisi, Maria; Chatterjee, Shami; Cordes, James M.; Cornish, Neil J.; Crawford, Fronefield; Cromartie, H. Thankful; Decesar, Megan E.; Demorest, Paul B.; Dolch, Timothy (2021-06-01). "The NANOGrav 11 yr Data Set: Limits on Supermassive Black Hole Binaries in Galaxies within 500 Mpc". The Astrophysical Journal. 914 (2): 121. arXiv:2101.02716. Bibcode:2021ApJ...914..121A. doi:10.3847/1538-4357/abfcd3. ISSN 0004-637X.