File:Messier_68_Hubble_WikiSky.jpg · Wikimedia Commons · See Wikimedia Commons
Messier 68 is a spherical collection of hundreds of thousands of old stars bound together by gravity, located about 33,000 light-years away in the constellation Hydra. Astronomers study globular clusters like this one to learn about the early history of our galaxy and the properties of ancient stars.
AI-generated from the Wikipedia summary — may contain errors.
Key facts
- Class
- X
- Constellation
- Hydra
- Right ascension
- 12 39 27.98
- Declination
- –26 ° 44 ′ 38.6 ″
- Distance
- 33.6 kly (10.3 kpc )
- Apparent dimensions v
- 11.0 ′
- Mass
- 2.23 × 10 M ☉
- Radius
- 53.5 ly
- Metallicity
- [ Fe/H ] = –2.23 dex
- Estimated age
- 11.2 Gyr
- Notable features
- Relatively metal poor.
- Other designations
- M68, NGC 4590, GCl 20
via Wikipedia infobox
Wikidata facts
- Distance from Earth
- 0.010
- Radius
- 53
- Image
- Messier 68 Hubble WikiSky.jpg
Show 14 more facts
- declination
- -26.744056
- Commons category
- Messier 68
- catalog code
- [KPS2012] MWSC 2059
- Commons gallery
- Messier 68
- absolute magnitude
- -7.3
- time of discovery or invention
- 1780-04-09
- right ascension
- 189.866583
- apparent magnitude
- 8.127
- radial velocity
- -116.0
- metallicity
- -2.18
- effective temperature
- 4549
- surface gravity
- 8
- right ascension component of proper motion
- -3.86
- declination component of proper motion
- 0.06
Sources (2)
via Wikidata · CC0
~2 min read
Article
Messier 68 (also known as M68 or NGC 4590) is a globular cluster found in the east south-east of Hydra, away from its precisely equatorial part. It was discovered by Charles Messier in 1780. William Herschel described it as "a beautiful cluster of stars, extremely rich, and so compressed that most of the stars are blended together". His son John noted that it was "all clearly resolved into stars of 12th magnitude, very loose and ragged at the borders".
M68 is centred about 33,600 light-years away from Earth. It is orbiting our galaxy's galactic bulge with a great eccentricity of 0.5. This takes it to 100,000 light years from the center. It is one of the most metal-poor globular clusters, which means it has a paucity of elements other than hydrogen and helium. The cluster may be undergoing core-collapse, and it displays signs of being in rotation. The cluster may have been acquired in its gravitational tie to the Milky Way through accretion from a satellite galaxy.