M107 (NGC 6171) Observation Guide — Globular Cluster in Ophiuchus

Overview

M107 is a globular cluster in Ophiuchus, catalogued as NGC 6171. At Magnitude 7.9, it lies roughly 21,000 light-years away. Summer evenings bring it to prime position, and the cluster suits intermediate observers.

Globular clusters are dense, spherical systems of hundreds of thousands to millions of stars, inhabiting the halo of the Milky Way. Among the oldest structures in the universe, they formed when the galaxy itself was young.

Basic Data

Physical Characteristics

M107 shines at Magnitude 7.9 from about 21,000 light-years away. It has a looser concentration than many globular clusters, making individual stars somewhat easier to resolve with modest apertures.

Observation Guide

Finding It

M107 is in Ophiuchus. Summer evenings around 8–10 PM bring it to a useful elevation in the south. Use Ophiuchus's main stars as reference points, then confirm the precise location with a star chart or app.

Tips for Observing

The brightness gradient from the core to the outer halo is the visual focus. Larger aperture separates more individual stars, turning the cluster from a fuzzy ball into a richly textured field.

Recommended Equipment

A small telescope with 60 mm aperture or more is sufficient.

Astrophotography Tips

Prime focus imaging through a tracking telescope is the standard approach. A well-judged exposure preserves core detail while reaching the fainter outer members.

Summary

M107 is an intermediate-level globular cluster in Ophiuchus — one of several satisfying cluster targets this constellation offers on summer nights.