Globular Cluster Messier 75

Messier 75
Messier 75: Image taken with the Hubble Space Telescope. © ESA/Hubble & NASA [215]

History

M 75 was discovered by French astronomer Pierre Méchain. Charles Messier reported: «A nebula without a star between Sagittarius and Capricorn's head: sighted by M Méchain on August 27th and 28th, 1780. M. Messier looked for him on October 5th and compared him to star no. 4 in Capricorn Flamsteed. It seemed to M. Messier that the nebula consisted only of small stars. M. Méchain reported a nebula without stars. M. Messier saw him on October 5th, but the moon was over the horizon. Only on the 18th could he determine his appearance and location.» [281]

Physical Properties

This globular cluster is of type I and has one of the densest core regions and is estimated to contain around 400'000 stars. Like most globular clusters, it is very old, around 13 billion years old, and is about 67'500 light years away from Earth. [215]

Revised+Historic NGC/IC Version 22/9, © 2022 Dr. Wolfgang Steinicke [277]
Designation NGC 6864
Type GCL (I)
Right Ascension (J2000.0) 20h 06m 04.8s
Declination (J2000.0) -21° 55' 15"
Diameter 6.8 arcmin
Visual magnitude 8.6 mag
Metric Distance 20.900 kpc
Dreyer Description globular, B, pL, R, vmbMBN, rr
Identification, Remarks M 75, GCL 116, ESO 595-SC13

Finder Chart

M 75 lies in a rather star-poor region between the figures of the constellations Sagittarius and Capricornus. The star 4 Capricorni is 5.8 mag bright and barely visible to the eye. The globular cluster lies 2° 45' west of it at almost the same declination.

Finder Chart Globular Cluster Messier 75
Globular Cluster Messier 75 in constellation Sagittarius. Charts created using SkySafari 6 Pro and STScI Digitized Sky Survey. Limiting magnitudes: Constellation chart ~6.5 mag, DSS2 close-ups ~20 mag. [149, 160]

More Objects Nearby (±15°)

References