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[M 73]

Messier 73

Observations and Descriptions

Discovered by Charles Messier on October 4 & 5, 1780.

Messier: M73.
October 4 & 5, 1780. 73. 20h 46m 52s (311d 43' 04") -13d 28' 40"
"Cluster of three or four small stars, which resembles a nebula at first sight, containing a little nebulosity: this cluster is situated on the same parallel as the preceding nebula [M72]: its position was determined from the same star Nu Aquarii."

(in Messier's handwritten notes on the discovery of the objects, he does not mention Nu Aquarii, and his description on how he measured M72 implies that this "Same Star" may actually be 6th-mag HD 198431 just west of M72.)

William Herschel
[Unpublished Observations of Messier's Nebulae and Clusters. Scientific Papers, Vol. 2, p. 658]
1783, Sept. 28. Consists of a few stars arranged in triangular form. No nebulosity among them. 10 ft., 150.

(from his description of M72)
This cluster [M72] is followed, at about 5m difference AR and 7' to the southward [thus at about RA 20h 40m, Dec S 13d 01'], by a trio of 10th-magnitude stars in a poor field: this is No. 73 of Messier's list, also registered in 1780.

John Herschel, General Catalogue: GC 4617.
GC 4617 = M73.
RA 20h 51m 16.0s, NPD 103d 10' 31.0" (1860.0) [Right Ascension and North Polar Distance]
Cl ??; eP; vlC; no neb 3 observations by W. & J. Herschel.
Cluster ??; extremely poor; very little compressed; no nebulosity.

Dreyer: NGC 6994.
NGC 6994 = GC 4617; M 73.
RA 20h 51m 16s, NPD 103d 10.5' (1860.0) [Right Ascension and North Polar Distance]
Cl, eP, vlC, no neb; = M73
Cluster, extremely poor, very little compressed, no nebulosity.
  • Observing Reports for M73 (IAAC Netastrocatalog)

    Hartmut Frommert
    Christine Kronberg

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    Last Modification: March 30, 2005