Citizens on the Spacewarps project have been searching for gravitational lenses. These are galaxies, or groups of galaxies (or any other massive object) that bend and magnify the light from a distant galaxy hidden behind them as viewed from Earth. These lenses are quite rare (we only know of around 400 of them at the moment). The above image shows one of the lens candidates discovered by the users on Spacewarps. The blue arc in the centre of the image is the light from a distant background galaxies being bent round the gravitational lens galaxy. This phenomenon allows scientists to gain glimpses of some of the most distant galaxies that telescopes would not usually be able to see, and also to learn about the mass composition of the lens galaxies. Read more about the lenses discovered by citizens read this Spacewarps blog post, and to have a go at finding them yourself check-out the project here.