Once you pry into the incredible world of stellar constellations, one particular cluster that stands out is Messier 71. This tightly-packed congregation of stars, also cataloged as NGC 6838, presents an enchanting spectacle for astronomers and star gazers alike.

The Remarkable Discovery

Messier 71 was found by Philippe Loys de Chéseaux in 1746. However, it was Charles Messier, renowned for his catalogue of astronomical objects, who gave it the identifiable tag M71 in the year 1780.

True Nature and Classification Dilemma

M71 was believed to be an open cluster for many decades. It wasn’t until the 20th century when scientists reclassified it as a loosely concentrated globular cluster, upturning previous observations. Its relatively youthful age and sparse population separate it from more densely-filled globular clusters.

Characteristics of Messier 71

This cluster grants a fantastic spectacle, flaunting its richness in variables and colorful stars. Many red and blue stragglers have been detected, hinting at the cluster’s intriguingly complex evolution.

• Age & Composition

  • Approximately 10 billion years old
  • Constituted primarily of helium and heavy elements

• Red and Blue Stragglers

  • A substantial number of red giants
  • Numerous blue stragglers suggesting stellar collision

Location in the Sky

Situated in the northern hemisphere, Messier 71 lies within the diminutive, but abundant in stars constellation Sagitta. As a guideline, it is located near the rich Milky Way star fields.

Observing Messier 71

With its begrudging angular diameter of about 7 arc minutes, spotting Messier 71 even by binoculars could prove challenging. Some of the finest telescopes might reveal the outer stars on a clear night. Its proximity to larger constellations such as Hercules or Lyra can help as guideposts.

How to Optimize your Observation

• Try finding it during summer or autumn, when Sagitta is high in the sky.
• Leverage star alignments with other constellations.
• High magnitude limit and minimal light pollution are key.

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Regardless of the viewing challenges, the allure of Messier 71 lies in its unique hybrid nature of a globular and open cluster. Let the celestial mystery of M71 draw you into the fascinating study of the stars.

Frequently Asked Questions

How Can I Spot Messier 71?

With a moderate telescope or binoculars, and minimal light pollution, you can use larger nearby constellations as a guide to locate Messier 71.

Why is Messier 71 Unique?

Formerly thought to be an open cluster, Messier 71 was reclassified as a globular cluster with attributes of both classes, making it pretty unique in the celestial sphere.

What is the Meaning of NGC 6838?

NGC 6838 is an alternate designation for Messier 71, coming from the New General Catalogue of Nebulae and Clusters of Stars.

Article updated at Monday, October 7, 2024