DDO 154

from Wikipedia, the free encyclopedia
Galaxy
DDO 154
{{{Card text}}}
Image of the irregular dwarf galaxy DDO 154 using the Hubble Space Telescope
Image of the irregular dwarf galaxy DDO 154 using the Hubble Space Telescope
AladinLite
Constellation Berenike's hair
Position
equinox :  J2000.0 , epoch : J2000.0
Right ascension 12 h 54 m 05.2 s
declination + 27 ° 08 ′ 59 ″
Appearance
Morphological type IB (s) m IV-V  
Brightness  (visual) 14.0 mag
Brightness  (B-band) 14.2 mag
Angular expansion 3 ′, 0 × 2 ′, 2
Physical data
Redshift 0.001248  
Radial velocity 374 km / s  
distance 14000000 Lj /
4300000 pc
history
discovery Sidney van den Bergh
Discovery date 1959
Catalog names
NGC  4789A • UGC  8024 • PGC  43869 • CGCG  159-109 • CGCG 160-4 • MCG  + 05-30-120 • 2MASX  J12540524 + 2708586 • NGC 4789A • DDO 154 • WBL 424-001 • BTS 158

DDO 154 , also NGC 4789A, is an irregular dwarf galaxy in the constellation Haar der Berenike . The discovery of the galaxy was published in 1959 by the astronomer Sidney van den Bergh . Its name NGC 4789A comes from the apparent proximity to the galaxy NGC 4789 ; however, it is not listed in the New General Catalog and is actually in an isolated position because of the difference in distance.

The mass of the interstellar hydrogen in DDO 154 is 10 8 solar masses , that of the stars 2.5 ⋅10 8 solar masses, according to another investigation results for non-ionized hydrogen 2.5 10 8 and a total of 3 ⋅10 8 solar masses, about one thousandth the Milky Way . A distance determination in 1984 using the Tully-Fisher relationship showed 10-12 Mpc , while more recent studies using blue star photometry indicate 4.3 Mpc.

Web links

Individual evidence

  1. ↑ SIMBAD query: DDO 154
  2. ↑ a b The Spitzer Local Volume Legacy (LVL) global optical photometry. . In: Monthly Notices of the Royal Astronomical Society . September. bibcode : 2014MNRAS.445..881C .
  3. ↑ a b L. Makarova, I. Karachentsev, LO Takalo, P. Heinämäki, M. Valtonen: Detailed images and distance measurements for eighteen dwarf irregular galaxies in the Canes Venatici cloud . In: Astronomy and Astrophysics Supplement . 1998. bibcode : 1998A & AS..128..459M .
  4. ^ Gérard-Henri de Vaucouleurs , Antoinette de Vaucouleurs, Harlow Shapley : Reference Catalog of Bright Galaxies . 1964 bibcode : 1964rcbg.book ..... D .
  5. ↑ Sydney van den Bergh: A catalog of dwarf galaxies. . In: Publ. David Dunlap Obs. . 1959. bibcode : 1959PDDO .... 2..145V .
  6. ↑ a b N. Krumm, D. Burstein: The extended hydrogen envelope around the dwarf galaxy DDO 154 . In: Astronomical Journal . 1984. bibcode : 1984AJ ..... 89.1319K .
  7. ↑ Stacy McGaugh, Jim Schombert: Weighing Galaxy Disks with the Baryonic Tully-Fisher Relation . In: The Astrophysical Journal . 2015. arxiv : 1501.06826 . bibcode : 2015ApJ ... 802 ... 18M .
  8. ↑ Claude Carignan, Chris Purton: The “Total” Mass of DDO 154 . In: The Astrophysical Journal . 1998. bibcode : 1998ApJ ... 506..125C .