NASA's veteran telescope snaps globular cluster NGC 6638 in constellation Sagittarius

This star-studded image shows the heart of the globular cluster NGC 6638 in the constellation Sagittarius. Captured using the NASA/ESA Hubble Space Telescope's Wide Field Camera 3 and the Advanced Camera for Surveys, the star-strewn observation highlights the density of stars at the heart of globular clusters.

Globular clusters are stable, tightly bound clusters of tens of thousands to millions of stars. While globular clusters are typically much larger than open clusters, they are far more densely populated, with populations ranging from tens of thousands to millions of stars.

This Hubble image of the globular cluster NGC 6638 was shared by the European Space Agency (ESA) on Monday.

This star-studded Picture of the Week from Hubble shows the heart of the globular cluster NGC 6638. The star-strewn observation highlights the density of stars at the heart of globular clusters.🔗 https://t.co/1KwlvUHkTRCredit: @esa / @HUBBLE_space / @NASA , R. Cohen pic.twitter.com/AiFwttFSJC

— HUBBLE (@HUBBLE_space) August 1, 2022

Atmospheric blurring makes it almost impossible for ground-based telescopes to clearly distinguish the stars in globular clusters from one another, but from Hubble's location in low Earth orbit, the atmosphere no longer poses a problem. The premium space-based observatory has been used to study what kind of stars globular clusters are made up of, how they evolve and the role of gravity in these dense systems.

The newly-launched James Webb Space Telescope will further peer into those globular clusters that are currently obscured by dust. The powerful telescope will predominantly observe at infrared wavelengths, which are less affected by the gas and dust surrounding newborn stars, and allow astronomers to inspect freshly formed star clusters.

Webb, a partnership between NASA, the European Space Agency and Canadian Space Agency, lifted off on an Ariane 5 rocket from Europe's Spaceport in French Guiana on 25 December 2021 on a long journey to unlock the secrets of the Universe. The observatory will solve mysteries in our solar system, look beyond distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it.