Gravitational lensing has to be one of the most visually striking phenomena in astronomy
Gravitational lensing is a phenomenon where a massive object bend the light of a distant source as it approaches the observer. Most often this takes the form of enormous galaxy clusters bending the light of even more distant galaxies into warped images of their true selves. They typically follow an arc around the massive object in the foreground like ripples in a pond.
Here's a few of my favourite gravitational lensing events.
Abel 1689 – Virgo
Abel 1689 is a one of the largest galaxy clusters in the known universe. It's located about 2.459 billion light-years away in constellation Virgo. Not only is this image visually beautiful, but the sheer number of gravitationally lensed galaxies across the entire image is just mind-blowing.
In 2008, one of the lensed galaxies, A1689-zD1, became known as the most distant galaxy from Earth based on a photometric redshift. 2008 also happens to be the same year the astronomy bug really bit me and it became one of my life-long passions.
PSZ1 G311.65-18.48 is a massive galaxy cluster located 4.6 billion light-years away in the constellation Apus. What's especially remarkable about this image is that it features a bright galaxy that's been lensed 12 separate times along four arcs. Three of these arcs are visible to the upper right of the cluster, while a fainter fourth arc is partially obscured by a bright foreground star to the bottom left of the cluster. This galaxy is almost 12 billion light-years away from Earth, which given its title as the brightest gravitationally lensed galaxy is quite a remarkable feat.