Globular Cluster Palomar 7 (IC 1276)

History

This globular cluster was discovered by American astronomer Lewis Swift on 10 April 1889 using the 16-inch Refractor at Warner Observatory, Rochester. Dreyer added it in 1895 as IC 1276 to his first «Index Catalogue» with the description: «Most extremely faint, very large, very difficult, double star close preceding.» [277, 314]

In 1952 the cluster was rediscovered by George Abell on the photo plates of the «Palomar Observatory Sky Survey» (POSS). In the list of 13 globular clusters it was listed as number 7, hence it also became known as Palomar 7. Abell noted: «Rich; highly obscured.» [331]

Physical Properties

Revised+Historic NGC/IC Version 22/9, © 2022 Dr. Wolfgang Steinicke [277]
Designation IC 1276
Type GCL (XII)
Right Ascension (J2000.0) 18h 10m 45.7s
Declination (J2000.0) -07° 12' 40"
Diameter 8 arcmin
Visual magnitude 10.3 mag
Metric Distance 5.400 kpc
Identification, Remarks GCL 90; Pal 7

Finder Chart

The globular cluster IC 1276 is located in the constellation Serpens. The constellation is best observable in the months of March to September.

Finder Chart Globular Cluster Palomar 7 (IC 1276)
Globular Cluster Palomar 7 (IC 1276) in constellation Serpens. 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]

Objects Within a Radius of 15°

References

  • [149] SkySafari 6 Pro, Simulation Curriculum; skysafariastronomy.com
  • [160] The STScI Digitized Sky Survey; archive.stsci.edu/cgi-bin/dss_form
  • [277] «Historische Deep-Sky Kataloge» von Dr. Wolfgang Steinicke; klima-luft.de/steinicke (2021-02-17)
  • [314] «Index Catalogue of Nebulæ found in the years 1888 to 1894, with Notes and Corrections to the New General Catalogue» Dreyer, J. L. E.; Memoirs of the Royal Astronomical Society, Vol. 51, p.185; 1895; Bibcode:1895MmRAS..51..185D
  • [331] «Globular Clusters and Planetary Nebulae Discovered on the National Geographic Society-Palomar Observatory Sky Survey» Abell, G. O.; Publications of the Astronomical Society of the Pacific, Vol. 67, No. 397, p.258-261, August 1955; DOI:10.1086/126815; Bibcode:1955PASP...67..258A