Using the PFIP imager on the William Herschel Telescope (WHT), astronomers have been able to trace for the first time the complete tidal stream surrounding the Sombrero galaxy, a galaxy which exhibits a rare morphology not yet fully explained.

With the naked eye, we can see some 3000 stars in a dark night. However, if Earth would reside within an ultra-diffuse galaxy, we would only spot a few dozen stars on the sky. Galaxies of this type were either not able to produce more stars in the first place, or they got stripped of their stars by tidal forces. Intriguingly, though, larger telescopes and improved imaging techniques have recently led to the discovery of many ultra-diffuse galaxies in the harshest environments possible: galaxy clusters.

NGC 660 is a polar ring galaxy at a distance of about 43 million light years in the constellation of Pisces. Polar ring galaxies are named as such because a substantial proportion of the stellar population, gas and dust orbit the galaxy is placed in rings around the nucleus. These rings are thought to be created by interaction with a neighbouring galaxy.

Some of the 11 known active asteroids originate in the main asteroid belt and thus are known as main belt comets (MBCs), one of the last discovered being P/2012 T1 (PANSTARRS). Thanks to the possibility of target-of-opportunity observations at the WHT and GTC, a team of Spanish astronomers followed up its evolution and revealed the origin of its cometary activity.

Some individual objects from the Galaxy Zoo project have gained a lot of attention from the public; the most famous of these is the ghost-like Voorwerp (the Dutch word for object), which was discovered by Dutch schoolteacher Hanny van Arkle. Observations with the William Herschel, among others, led astronomers to the conclusion that this object consists of a cloud of highly ionized gas.