Grupul Local

De la Wikipedia, enciclopedia liberă
Salt la: Navigare, căutare
Un membru al Grupului Local, galaxia pitică iregulară Sextans A

Grupul Local este un grup de galaxii ce cuprinde și Calea Lactee. Acesta conține aproximativ 30 de galaxii, incluzând și galaxii pitice, centrul gravitațional al grupului fiind undeva între Calea Lactee și galaxia Andromeda. Galaxiile Grupului Local sunt răspândite pe un diametru de 100 milioane de ani-lumină (sau 1 E+22 m).

Cele mai masive galaxii din grup sunt Calea Lactee și Andromeda. Fiecare din cele două galaxii spiralate are câte un sistem propriu de sateliți:

Harta[modificare | modificare sursă]

Sextans B Sextans A Milky Way Leo I (dwarf galaxy) Canes Dwarf Leo II (dwarf galaxy) NGC 6822 Phoenix Dwarf Tucana Dwarf Wolf-Lundmark-Melotte Cetus Dwarf IC 1613 SagDIG Aquarius Dwarf Triangulum Galaxy NGC 185 NGC 147 IC 10 Andromeda Galaxy M110 Leo A NGC 3109 Antlia Dwarf LGS 3 Pegasus Dwarf Andromeda II Andromeda III Andromeda I
Despre această imagine
Local Group (clickable map)

Componenta Grupului Local[modificare | modificare sursă]

Galaxie spirala
nume tip constelatie note
Milky Way SBbc Sagittarius (centre) Casa noastrea, a doua galaxie ca marime.[1]
Andromeda (M31, NGC 224) SA(s)b Andromeda Aproximativ 220000 ani lumina in diameter, cea mai mare galaxie din Gruop
Triangulum (M33, NGC 598) SA(s)cd Triangulum A treia galaxie, este o posibila galaxie-satelit a Andromedei
Galaxie Eliptica
nume tip constelatie note
M32 (NGC 221) E2 Andromeda satelit al Galaxiei Andromeda
Galaxii iregulate
nume tip constelatie note
Wolf–Lundmark–Melotte (WLM, DDO 221) Ir+ Cetus
IC 10 KBm or Ir+ Cassiopeia
Micul Nor al lui Magelan (SMC, NGC 292) SB(s)m pec Tucana satelit al Calei Lactee
Galaxia Pitică Câinele Mare Irr Canis Major satellite of Milky Way
Galaxia pitica Pesti (LGS3) Irr Pisces satellite of the Triangulum Galaxy?
IC 1613 (UGC 668) IAB(s)m V Cetus
Galaxia Pitica Pheonix Irr Phoenix
Large Magellanic Cloud (LMC) Irr/SB(s)m Dorado Fourth largest member of the group, satellite of Milky Way
Leo A (Leo III) IBm V Leo
Sextans B (UGC 5373) Ir+IV-V Sextans
NGC 3109 Ir+IV-V Hydra
Sextans A (UGCA 205) Ir+V Sextans
Galaxii eliptice pitice
name type constellation notes
M110 (NGC 205) dE6p Andromeda satellite of the Andromeda Galaxy
NGC 147 (DDO 3) dE5 pec Cassiopeia satellite of the Andromeda Galaxy
SagDIG (Sagittarius Dwarf Irregular Galaxy) IB(s)m V Sagittarius Most remote from barycenter member thought to be in the Local Group.[2]
NGC 6822 (Barnard's Galaxy) IB(s)m IV-V Sagittarius
Pegasus Dwarf (Pegasus Dwarf Irregular, DDO 216) Irr Pegasus
Galaxii sferoidale pitice
nume tip constelatie note
Boötes I dSph Boötes
Cetus Dwarf dSph/E4 Cetus
Canes Venatici I Dwarf and Canes Venatici II Dwarf dSph Canes Venatici
KKs 3 dSph
Andromeda III dE2 Andromeda satellite of the Andromeda Galaxy
NGC 185 dE3 pec Cassiopeia satellite of the Andromeda Galaxy
Andromeda I dE3 pec Andromeda satellite of the Andromeda Galaxy
Sculptor Dwarf (E351-G30) dE3 Sculptor satellite of Milky Way
Andromeda V dSph Andromeda satellite of the Andromeda Galaxy
Andromeda II dE0 Andromeda satellite of the Andromeda Galaxy
Fornax Dwarf (E356-G04) dSph/E2 Fornax satellite of Milky Way
Carina Dwarf (E206-G220) dE3 Carina satellite of Milky Way
Antlia Dwarf dE3/dSph/Irr? Antlia
Leo I (DDO 74) dE3 Leo satellite of Milky Way
Sextans Dwarf dE3 Sextans satellite of Milky Way
Leo II (Leo B) dE0 pec Leo satellite of Milky Way
Ursa Minor Dwarf dE4 Ursa Minor satellite of Milky Way
Draco Dwarf (DDO 208) dE0 pec Draco satellite of Milky Way
SagDEG (Sagittarius Dwarf Elliptical Galaxy) dSph/E7 Sagittarius satellite of Milky Way
Tucana Dwarf dE5 Tucana
Cassiopeia Dwarf (Andromeda VII) dSph Cassiopeia satellite of the Andromeda Galaxy
Pegasus Dwarf Spheroidal Galaxy (Andromeda VI) dSph Pegasus satellite of the Andromeda Galaxy
Ursa Major I Dwarf and Ursa Major II Dwarf dSph Ursa Major satellite of Milky Way
Leo IV dSph Leo satellite of the Milky Way
Leo V dSph Leo satellite of the Milky Way
Leo T dSph/Irr Leo satellite of the Milky Way
Boötes II dSph Boötes satellite of the Milky Way
Boötes III dSph Boötes satellite of the Milky Way
Coma Berenices dSph Coma Berenices satellite of the Milky Way
Segue 2 dSph Aries satellite of the Milky Way
Hercules dSph Hercules satellite of the Milky Way
Pisces II dSph Pisces satellite of the Milky Way
Reticulum II dSph Reticulum satellite of the Milky Way
Eridanus II dSph Eridanus satellite of the Milky Way
Grus dSph Grus satellite of the Milky Way
Tucana II dSph Tucana satellite of the Milky Way
Identificare incerta
nume tip constelatie note
Virgo Stellar Stream dSph (remnant)? Virgo In the process of merging with the Milky Way
Willman 1 dwarf Spherical galaxy
or Globular cluster?
Ursa Major 147,000 light-years away
Andromeda IV Irr? Andromeda probably not a galaxy
UGCA 86 (0355+66) Irr, dE or S0 Camelopardalis
UGCA 92 (EGB0427+63) Irr or S0 Camelopardalis
Horologium dSph or Globular Cluster Horologium satellite of the Milky Way
Pictoris dSph or Globular Cluster Pictor satellite of the Milky Way
Phoenix II dSph or Globular Cluster Phoenix satellite of the Milky Way
Indus dSph or Globular Cluster Indus satellite of the Milky Way
Eridanus III dSph or Globular Cluster Eridanus satellite of the Milky Way
Probabili non membri
name type constellation notes
GR 8 (DDO 155) Im V Virgo
IC 5152 IAB(s)m IV Indus
NGC 55 SB(s)m Sculptor
Aquarius Dwarf (DDO 210) Im V Aquarius
NGC 404 E0 or SA(s)0 Andromeda
NGC 1569 Irp+ III-IV Camelopardalis
NGC 1560 (IC 2062) Sd Camelopardalis
Camelopardalis A Irr Camelopardalis
Argo Dwarf Irr Carina
ESO 347-8 (2318–42) Irr Grus
UKS 2323-326 Irr Sculptor
UGC 9128 (DDO 187) Irp+ Boötes
Sextans C
Obiecte din Grupul Local nerecunoscute ca si galaxii
nume tip constelatie note
Palomar 12 (Capricornus Dwarf) Capricornus a globular cluster formerly classified as a dwarf spheroidal galaxy
Palomar 4 (originally designated Ursa Major Dwarf) Ursa Major a globular cluster formerly classified as a dwarf spheroidal galaxy

Diagrama[modificare | modificare sursă]

A diagram of our location in the observable universe. (Click here for smaller image.)
A diagram of our location in the observable universe. (Click here for smaller image.)


  1. ^ http://www.atlasoftheuniverse.com/galaxies.html
  2. ^ van den Bergh, Sidney (1 aprilie 2000). „Updated Information on the Local Group”. The Publications of the Astronomical Society of the Pacific 112 (770): 529–536. doi:10.1086/316548. Bibcode2000PASP..112..529V