NGC 3201

NGC 3201

NGC 3201
NGC 3201 by Hubble Space Telescope; 3.5′ view
Credit: NASA/STScI/WikiSky
Observation data (J2000 epoch)
Class X[1]
Constellation Vela
Right ascension 10h 17m 36.82s[2]
Declination –46° 24′ 44.9″[2]
Distance 16.3 kly (5.0 kpc)[3]
Apparent magnitude (V) +8.24[4]
Apparent dimensions (V) 18′.2
Physical characteristics
Mass 2.54×105[5] M
Radius 40 ly[6]
VHB 14.77
Metallicity –1.24[7] dex
Estimated age 10.24 Gyr[7]
Other designations GCl 15,[4] GC 2068, h 3238, Dun 445, Bennett 44, Caldwell 79[8]
Colour-composite image of NGC 3201, obtained with the WFI instrument on the ESO/MPG 2.2-m telescope at La Silla Observatory

NGC 3201 is a low galactic latitude globular cluster in the southern constellation of Vela. It has a very low central concentration of stars.[9] This cluster was discovered by James Dunlop on May 28, 1826 and listed it in his 1827 catalogue. He described it as "a pretty large pretty bright round nebula, 4′ or 5′ diameter, very gradually condensed towards the centre, easily resolved into stars; the figure is rather irregular, and the stars are considerably scattered on the south".[10]

The radial velocity of this cluster is unusually high at 490 km/s, larger than any other cluster known. This corresponds to a peculiar velocity of 240 km/s. While high, this is lower than the escape velocity of the Milky Way galaxy.[10] It is located at a distance of 16,300 light years from the Sun and has an estimated 254,000 times the mass of the Sun.[3] This cluster is about 10.24 billion years old.[7]

The stellar population of this cluster is inhomogeneous, varying with distance from the core. The effective temperature of the stars shows an increase with greater distance, with the redder and cooler stars tending to be located closer to the core. As of 2010, is one of only two clusters (including Messier 4) that shows a definite inhomogeneous population.[11]

References

  1. ^
  2. ^ a b
  3. ^ a b
  4. ^ a b
  5. ^
  6. ^ distance × sin( diameter_angle / 2 ) = 40 ly. radius
  7. ^ a b c
  8. ^
  9. ^
  10. ^ a b
  11. ^

External links

  • Globular Cluster NGC 3201 at SEDS pages
  • NGC 3201 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images
  • NGC 3201 at DOCdb (Deep Sky Observer's Companion)