The latest image released by Hubble is a stunning reminder of just how incredible this observatory is, decades after it was sent to space and without any refurbishment since 2009. The photograph focuses on the core of globular star cluster NGC 6540 and positively sparkles. This tightly bound group of stars is 17,000 light-years from Earth and Hubble’s keen eye shows it to us in spectacular detail.
Globular clusters such as these have between tens of thousands to a million stars and are very useful for astronomers. They tend to form together so it is easier to estimate their age. In particular, studying NGC 6540 helps astronomers to understand the globular clusters that surround the core of the Milky Way, providing insights into the formation and very early evolution of our galaxy.
The glistening effects of some of the brightest stars in the system make for a gorgeous effect but it is an artifact of diffraction of light around the telescope’s structure. JWST also creates such an effect but its hexagonal geometry leads to six large spikes in those images.
This is a timely reminder that Hubble is not done yet, and is still carrying out fantastic science. JWST stands on the shoulders of Hubble and for that we're thankful.