Annika H. G. Peter

The red dot in the James Webb Space Telescope image is the galaxy Bz5.3, whose light has traveled 12.5 billion years to reach us. It lies behind the Bullet Cluster, whose gravitational field acted as a lens and brightened it by a factor of 3.7.

The Bullet Cluster is a cosmic collision site where two vast clouds of galaxies, gas, and invisible matter slammed into each other. When light from distant stars passes near such a cluster, gravity bends its path like a lens. Astronomers study these distortions to work out where the mass is hiding.