The Wide Field Camera 3 on the NASA/ESA Hubble Space Telescope has captured a stunning image of the Quintuplet Cluster, a very dense cluster of young stars near the center of our Milky Way Galaxy.
This new Hubble image shows a massive open star cluster known as the Quintuplet Cluster in infrared light. Image credit: ESA / Hubble / NASA.
Named for its five bright red stars, the Quintuplet Cluster is one of the most massive young open star clusters known.
It is about 25,000 light-years from Earth and just 100 light-years from the center of our Galaxy.
Its proximity to the dust at the Galactic Center means that much of its visible light is blocked, which helped to keep the cluster unknown until its discovery in 1990, when it was revealed by observations in the infrared.
Infrared images of the cluster, like the one shown here, allow us to see through the obscuring dust to the hot stars in the cluster.
The cluster hosts two luminous blue variable stars: V4650 Sgr and the Pistol Star. If you were to draw a line horizontally through the center of this Hubble image from left to right, you could see the Pistol Star hovering just above the line about one third of the way along it.
The Pistol Star is one of the most luminous known stars in the Milky Way and takes its name from the shape of the Pistol Nebula that it illuminates. The nebula is so big (4 light-years) that it would nearly span the distance from the Sun to Alpha Centauri, the nearest star to our Solar System.
Astronomers estimate that when the Pistol Star was formed 1 – 3 million years ago, it may have weighed up to 200 times the mass of the Sun before shedding much of its mass in violent eruptions.
The Quintuplet Cluster also contains a number of red supergiant stars. These stars are among the largest in the Galaxy and are burning their fuel at an incredible speed, meaning they will have a very short lifetime.
Their presence suggests an average cluster age of around 4 million years. At the moment these stars are on the verge of exploding as supernovae.
