Globular Cluster Messier 80

Messier 80
Messier 80: Image taken with the Hubble Space Telescope. © ESA/Hubble & NASA [215]

History

The globular cluster M 80 was discovered by Charles Messier on 4 January 1781. He wrote: «Nebula without a star, in Scorpio between the stars ρ and δ, compared to ρ for determining the position: The nebula is round, the center brilliant, looks like the core of a comet wrapped in nebula. M. Méchain saw it on 28 January 1781.» [281]

Physical Properties

About 28'000 light years away is M 80, one of the densest of the 150 known globular clusters in our Milky Way. This globular cluster contains several hundred thousand stars, which are held together by their mutual attraction. In 1860 a nova occurred in this globular cluster. Novas can arise when a nearby companion star transfers fresh hydrogen to a burned-out white dwarf. This can lead to a thermonuclear explosion on the surface of the white dwarf and a brief increase in brightness. A large number of blue stragglers were also found in the cluster, stars that are unusually young for globular clusters. [215]

Revised+Historic NGC/IC, Version 22/9, © Dr. Wolfgang Steinicke [277]
DesignationNGC 6093
TypeGCL (II)
Right Ascension16h 17m 02.5s
Declination-22° 58' 28"
Diameter10 arcmin
Visual magnitude7.3 mag
Metric Distance10.000 kpc
Dreyer Description!! globular, vB, L, vmbM (var *), rrr, st 14
Identification, RemarksM 80, GCL 39, ESO 516-SC11

Finder Chart

M 80 is located in the constellation Scorpius between the stars ρ Ophiuchi and δ Scorpii. It can best be observed in the months of May to July.

Chart Globular Cluster Messier 80
Globular Cluster Messier 80 in constellation Scorpius. Chart created using SkySafari 6 Pro and STScI Digitized Sky Survey. [149, 160]

More Objects Nearby (±15°)

References

149SkySafari 6 Pro, Simulation Curriculum; skysafariastronomy.com
160The STScI Digitized Sky Survey; archive.stsci.edu/cgi-bin/dss_form
215Explore - The Night Sky | Hubble’s Messier Catalog; nasa.gov/content/goddard/hubble-s-messier-catalog (2020-12-31)
277«Historische Deep-Sky Kataloge» von Dr. Wolfgang Steinicke; klima-luft.de/steinicke (2021-02-17)
281«Catalogue Nébuleuses et des Amas D'Étoiles» Observées à Paris, par M. Messier, à l'Observatoire de la Marine, hôtel de Clugni, rue des Mathurins. «Connoissance des temps ou connoissance des mouvements célestes, pour l'année bissextile 1784 » Page 227; gallica.bnf.fr/ark:/12148/bpt6k6514280n/f235 (2021-02-21)