Messier 69

This globular cluster is one of the most metal-rich ever observed.

Distance

29,700 light-years

Apparent Magnitude

8.3

constellation

Sagittarius

object type

Globular Cluster

M69
This dazzling image shows the globular cluster Messier 69, or M 69 for short, as viewed through the NASA/ESA Hubble Space Telescope. Globular clusters are dense collections of old stars. In this picture, foreground stars look big and golden when set against the backdrop of the thousands of white, silvery stars that make up M 69. Another aspect of M 69 lends itself to the bejewelled metaphor: As globular clusters go, M 69 is one of the most metal-rich on record. In astronomy, the term “metal” has a specialised meaning: it refers to any element heavier than the two most common elements in our Universe, hydrogen and helium. The nuclear fusion that powers stars created all of the metallic elements in nature, from the calcium in our bones to the carbon in diamonds. Successive generations of stars have built up the metallic abundances we see today. Because the stars in globular clusters are ancient, their metallic abundances are much lower than more recently formed stars, such as the Sun. Studying the makeup of stars in globular clusters like M 69 has helped astronomers trace back the evolution of the cosmos. M 69 is located 29 700 light-years away in the constellation Sagittarius (the Archer). The famed French comet hunter Charles Messier added M 69 to his catalogue in 1780. It is also known as NGC 6637. The image is a combination of exposures taken in visible and near-infrared light by Hubble’s Advanced Camera for Surveys, and covers a field of view of approximately 3.4 by 3.4 arcminutes.
ESA/Hubble & NASA

M69 is one of the most metal-rich globular clusters ever observed. In astronomy, the term “metal” refers to any element heavier than the two most common elements in our universe, hydrogen and helium. The nuclear fusion that powers stars created many of the metallic elements in nature, from the calcium in our bones to the carbon in diamonds. New stars are made from the remains of their predecessors, so ancient globular clusters have much lower metallic abundances than more recently formed stars, such as the sun.

The stars in M69 have over ten times more iron than stars in other globular clusters of the same age. Studying the makeup of stars in globular clusters like M69 has helped astronomers trace back the evolution of star formation in the cosmos.

This cluster was discovered by Charles Messier in 1780. It is located 29,700 light-years away from Earth in the constellation Sagittarius. M69 has an apparent magnitude of 8.3 and can be spotted with a pair of binoculars most easily in August. This Hubble image of M69’s center is a composite of exposures taken in visible and infrared light.

For more information about Hubble’s observations of M69, see:

locator star chart for M69
This star chart for M69 represents the view from mid-northern latitudes for the given month and time.
Image courtesy of Stellarium

Explore Hubble's Messier Catalog

The following pages contain some of Hubble’s best images of Messier objects.

Bright green, orange, and yellow tendrils intertwined within this egg shaped nebula.

Messier 1 (The Crab Nebula)

Better known as the Crab Nebula, Charles Messier originally mistook Messier 1 for Halley’s Comet, which inspired him to create…

A Hubble image of a ball of thousands of stars

Messier 2

Hubble's image of Messier 2 is comprised of visible and infrared wavelengths of light.

Hubble view of M3 - a ball of thousands of stars.

Messier 3

Messier 3 holds more than 500,000 stars.