Back السدس B Arabic Sextans B Catalan Sextans B German Sextans B Spanish Sextans B Finnish Galaxie du Sextant B French גלקסיית סקסטנט B HE Sestante B Italian Sextans B LB Sekstant B Polish

Sextans B

Sextans B
Observation data (J2000 epoch)
ConstellationSextans
Right ascension10h 00m 00.1s[1]
Declination+05° 19′ 56″[1]
Redshift300 ± 0 km/s[1]
Distance4.44 ± 0.23 Mly (1.36 ± 0.07 Mpc)[2][3]
Apparent magnitude (V)11.9[1]
Characteristics
TypeImIV–V[1]
Apparent size (V)5.1′ × 3.5′[1]
Other designations
UGC 5373,[1] PGC 28913,[1] DDO 70,[1] Sex B[1]
Preview warning: Page using Template:Infobox galaxy with unknown parameter "image_size"

Sextans B (also known as UGC 5373 and DDO 70) is an irregular galaxy that may be part of the Local Group, or lie just beyond it. Sextans B is 4.44 million light-years away from Earth and thus is one of the most distant members of the Local Group, if it is indeed a member. It forms a pair with its neighbouring galaxy Sextans A.[4] It is a type Ir IV–V galaxy according to the galaxy morphological classification scheme.[5] Sextans B may also be gravitationally associated with the galaxies NGC 3109 and the Antlia Dwarf.[6]

Sextans B has a uniform stellar population,[7] but the interstellar medium in it may be inhomogeneous.[8] Its mass is estimated to be about 2×108 times the mass of the Sun, of which 5.5×107 is in the form of atomic hydrogen.[7] Star formation in the galaxy seems to have proceeded in distinct periods of low intensity, separated by shorter periods of no activity.[7] The existence of Cepheid variables in the galaxy implies that Sextans B contains at least some young stars.[5] The metallicity of Sextans B is very low, with a value of approximately Z = 0.001.[7] Sextans B is receding from the Milky Way with a speed of approximately 300 kilometres per second (190 mi/s),[8] and probably lies just outside the edge of the Local Group, so as its neighbour Sextans A.[9]

Five planetary nebulae have been identified in Sextans B, which is one of the smallest galaxies where planetary nebulae have been observed. These appear point-like and can be identified by their spectral emission lines.[10] It also contains a massive globular cluster.[11]

  1. ^ a b c d e f g h i j "NASA/IPAC Extragalactic Database". Results for Sex B. Retrieved 2006-12-13.
  2. ^ I. D. Karachentsev; V. E. Karachentseva; W. K. Hutchmeier; D. I. Makarov (2004). "A Catalog of Neighboring Galaxies". Astronomical Journal. 127 (4): 2031–2068. Bibcode:2004AJ....127.2031K. doi:10.1086/382905.
  3. ^ Karachentsev, I. D.; Kashibadze, O. G. (2006). "Masses of the local group and of the M81 group estimated from distortions in the local velocity field". Astrophysics. 49 (1): 3–18. Bibcode:2006Ap.....49....3K. doi:10.1007/s10511-006-0002-6. S2CID 120973010.
  4. ^ Cite error: The named reference SandageCarlson1985 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference vandenBergh2000 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference vandenbergh1999 was invoked but never defined (see the help page).
  7. ^ a b c d Cite error: The named reference TosiEtAl1991 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference KniazevEtAl2005 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference AlloinGieren was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference MagriniEtAl2002 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference SharinaEtAl2007 was invoked but never defined (see the help page).

Rich TVX News Network Site

Rich TVX News Network Info

© MMXXIII Rich X Search. We shall prevail. All rights reserved. Rich X Search