NGC 7385

NGC 7385
HST image of NGC 7385
Observation data (J2000 epoch)
ConstellationPegasus
Right ascension22h 49m 54.58s
Declination+11° 36′ 30.84″
Redshift0.026175
Heliocentric radial velocity7,847 ± 10 km/s
Distance359.8 ± 25.2 Mly (110.31 ± 7.73 Mpc)
Group or clusterZwicky 2247.3+1107
Absolute magnitude (V)12.2
Characteristics
TypecD; E pec, LERG
Size~164,000 ly (50.2 kpc) (estimated)
Other designations
UGC 12207, MCG +02-58-017, PGC 69824, CGCG 430-015, 4C +11.71, GIN 663, Cul 2247+13, MRC 2247+113, PKS 2247+11, TXS 2247+113

NGC 7385 is an elliptical galaxy located in the constellation of Pegasus. The redshift of the galaxy is (z) 0.026 and it was first discovered by William Herschel in October 1784 who described it as a small round faint object, but also observed by John Herschel in 1827.

Description

SDSS image of NGC 7385.

NGC 7385 is a member of the galaxy cluster, Zwicky 2247.3+1107. It is a peculiar early-type elliptical galaxy with a Type E1 classification and has a measured velocity of 7,827 kilometers per seconds. The absolute blue magnitude has been estimated to be -21.83.

The nucleus has been found active and it has been classified as a Fanaroff-Riley Type I head-tail radio galaxy hosting a radio source called PKS 2247+11. There is a presence of a head component known to coincide with the optical position of the galaxy and a tail component found extending by 12 arcseconds in position angle of 209 degrees. Further imaging found there is a diffused component located on the nucleus in an opposite direction where the tail is located with a measured flux density of 243 ± 7 mJy. The dynamical age of the source has been estimated as 1,010 million years with the total extent of the source being 442.3 kiloparsecs.

Radio imaging made with Very Large Array discovered a radio jet on one side, which in turn extends towards the south-west direction from the unresolved radio core. An X-ray jet counterpart was discovered in addition with further presence of faint X-ray emission covering over an area of 5 arcseconds.

The head component when observed through high-resolution radio imaging at 5 GHz frequencies, is further split into two separate components. The first component is associated with main galaxy's nucleus whereas the other component is located in the opposite side of the tail position and also associated with a blue knot feature. Further evidence found the optical spectrum of the knot has presence of emission lines of forbidden singly ionized oxygen, doubly ionized oxygen and H-beta elements. A H II region has been detected at the radio lobe edge, likely caused via interactions of both plasma and surrounding interstellar medium.

References

  1. 1 2 3 4 5 6 7 8 9 "NED search results for NGC 7385". ned.ipac.caltech.edu. Archived from the original on 2025-03-30. Retrieved 2026-11-05.
  2. ↑ "Revised NGC Data for NGC 7385". spider.seds.org. Retrieved 30 March 2024.
  3. ↑ Thomsen, B.; Frandsen, S. (June 1983). "Surface brightness and effective radius for elliptical galaxies". The Astronomical Journal. 88: 789. doi:10.1086/113366. ISSN 0004-6256. Archived from the original on 2024-09-05.
  4. ↑ "NGC Objects: NGC 7350 - 7399". cseligman.com. Retrieved 2026-11-05.
  5. 1 2 T., Schilizzi, R.; D., Ekers, R. (April 1975). "Radio tail source associated with NGC 7385". Astronomy and Astrophysics. 40. ISSN 0004-6361. Archived from the original on 2024-04-29.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  6. ↑ B., Sparks, W.; H., Hough, J.; J., Axon, D.; J., Bailey, (February 1986). "Infrared photometry of the nuclei of early-type radio galaxies". Monthly Notices of the Royal Astronomical Society. 218. doi:10.1093/mnra. ISSN 0035-8711. Archived from the original on 2025-04-13.{{cite journal}}: CS1 maint: extra punctuation (link) CS1 maint: multiple names: authors list (link)
  7. ↑ Impey, C. D.; Wynn-Williams, C. G.; Becklin, E. E. (February 1986). "Infrared studies of elliptical galaxies. I - an optically selected sample". The Astrophysical Journal. 309: 572. doi:10.1086/164626. ISSN 0004-637X. Archived from the original on 2025-06-12.
  8. ↑ James, P. A.; Mobasher, B. (1999-06-11). "Stellar population of ellipticals in different environments: near-infrared spectroscopic observations". Monthly Notices of the Royal Astronomical Society. 306 (1): 199–206. doi:10.1046/j.1365-8711.1999.02479.x. ISSN 0035-8711. Archived from the original (PDF) on 2024-12-28.
  9. ↑ S., Scott, J.; W., Robertson, J.; M., Tarenghi, (July 1977). "Spectroscopic study of two clusters of galaxies: Abell 2634 and Zw 2247+11". Astronomy and Astrophysics. 59. ISSN 0004-6361. Archived from the original on 2024-11-30.{{cite journal}}: CS1 maint: extra punctuation (link) CS1 maint: multiple names: authors list (link)
  10. ↑ Reddy, Karthik; Georganopoulos, Markos; Meyer, Eileen T.; Keenan, Mary; Kollmann, Kassidy E. (2023-02-20). "Offsets between X-Ray and Radio Components in X-Ray Jets: The AtlasX". The Astrophysical Journal Supplement Series. 265 (1): 8. doi:10.3847/1538-4365/aca321. ISSN 0067-0049. Archived from the original on 2024-07-23.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  11. ↑ G., Robertson, J. (January 1981). "Further observations of the head-tail radio galaxy PKS 2247 + 11". Astronomy and Astrophysics. 93 (1–2). ISSN 0004-6361. Archived from the original on 2024-08-18.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  12. 1 2 Hardee, P. E.; Eilek, J. A.; Owen, F. N. (December 1980). "NGC 7385 - Generation of an H II region by thermal instability associated with the creation of a radio source". The Astrophysical Journal. 242: 502. doi:10.1086/158483. ISSN 0004-637X. Archived from the original on 2024-11-08.
  13. ↑ Sebastian, Biny; Lal, Dharam V.; Rao, A. Pramesh (2017-09-29). "Giant Metrewave Radio Telescope Observations of Head–Tail Radio Galaxies". The Astronomical Journal. 154 (4): 169. doi:10.3847/1538-3881/aa88d0. ISSN 0004-6256.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  14. ↑ Rawes, J.; Worrall, D. M.; Birkinshaw, M. (2015-07-29). "Discovery of an optical and X-ray synchrotron jet in NGC 7385". Monthly Notices of the Royal Astronomical Society. 452 (3): 3064–3072. doi:10.1093/mnras/stv1501. ISSN 0035-8711.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  15. ↑ Simkin, S. M.; Ekers, R. D. (January 1979). "An optical-radio knot in NGC 7385". The Astronomical Journal. 84: 56. doi:10.1086/112387. ISSN 0004-6256. Archived from the original on 2024-09-04.