It is a globular cluster located in the constellation Sagittarius located approximately 13 000 light years from Earth.
For a long time, the classification of M71 was a dense open cluster, but nowadays it's pretty inconclusive, with little study to help astronomers understand exactly what the M71 is. One of great importance was in 2008, when Brazilian astronomer Alan Alves-Brito and his colleagues published a study entitled “Abundance variations in globular cluster M71 (NGC 6838), where they measured the indices of cyanide, hydrocarbons, calcium, magnesium and aluminum in the spectra of 89 different stars, as well as their radial velocities, colors, luminosity, effective temperatures and gravities.
Hence why today. M71 is classified as a very loosely concentrated globular cluster, much like M68 in the constellation Hydra.
Best details:
https://www.astrobin.com/full/czc0dz/0/
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Date: 07/13/2021
Location: Jales-SP-Brazil
Copyright: Fernando Oliveira de Menezes
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