Hubble captures an open star cluster in a nearby satellite galaxy

By Georgina Torbet December 3, 2022

The Hubble Space Telescope recently captured an image of a beautiful star cluster called NGC 1858, located in an area full of star-forming regions. This area is part of the Large Magellanic Cloud, one of the Milky Way’s satellite galaxies, and is located 160,000 light-years away and is thought to be around 10 million years old.

The Large Magellanic Cloud is one of several satellite galaxies to the Milky Way, which are smaller galaxies that are gravitationally bound to our galaxy. Along with its companion, the Small Magellanic Cloud, it orbits around the Milky Way and will eventually collide with our galaxy in billions of years’ time.

Against a backdrop littered with tiny pinpricks of light glint a few, brighter stars. This whole collection is NGC 1858, an open star cluster in the northwest region of the Large Magellanic Cloud, a satellite galaxy of our Milky Way that boasts an abundance of star-forming regions. NGC 1858 is estimated to be around 10 million years old.clock — Against a backdrop littered with tiny pinpricks of light glint a few, brighter stars. This whole collection is NGC 1858, an open star cluster in the northwest region of the Large Magellanic Cloud, a satellite galaxy of our Milky Way that boasts an abundance of star-forming regions. NGC 1858 is estimated to be around 10 million years old. NASA, ESA and G. Gilmore (University of Cambridge); Processing: Gladys Kober (NASA/Catholic University of America)

This particular star cluster is a type called an open cluster, which means it is not as tightly bound by gravity as some other structures and has a more irregular shape. In addition, the amount of dust and gas present here means that it can be classified as an emission nebula, as light from the stars in the region has ionized the gas and caused it to emit its own light.

These features make this region of scientific interest in learning about star formation. “The stars within this young cluster are at different phases of their evolution, making it a complex collection,” Hubble scientists write. “Within NGC 1858, researchers have detected a protostar, a very young, emerging star, indicating that star formation within the cluster may still be active or has stopped very recently. The presence of an emission nebula also suggests that star formation recently occurred here, since the radiation required to ionize the gas of the nebula comes from stars that only live a short time.”

The image was taken using both visible light and infrared wavelengths. Although Hubble primarily operates in the visible light range, its instruments can also look in some regions of the infrared, allowing researchers to build up a more complete picture of complex structures of dust and gas such as nebulae.

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Georgina Torbet

Space Writer

Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…

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