What is the name of the Hubble image that celebrates its 25th anniversary?

The Hubble image chosen to celebrate the telescope’s 25th anniversary was Westerlund 2. Released on 23 April 2015, it shows a young, densely packed star cluster surrounded by glowing gas in the constellation Carina.

Westerlund 2 is an open star cluster discovered by Swedish astronomer Bengt Westerlund in the 1960s. It lies within the larger star-forming region RCW 49 and contains many hot, massive young stars. Astronomers estimate that the cluster is only about two million years old, making it a valuable laboratory for studying how stars form and evolve.

The anniversary image combined observations from Hubble’s visible-light and infrared capabilities. Infrared imaging helps reveal stars hidden behind dust, while visible-light observations show the surrounding nebula’s intricate structure. The result is often mistaken for a generic colorful nebula photograph, but the named subject is the star cluster itself.

This anniversary choice also highlighted Hubble’s role in making complex astronomical research accessible to the public. The telescope was launched in 1990 and had already transformed astronomy through detailed views of star birth, galaxies, nebulae, and the expanding universe.