This planet, GJ 504b, is about the size of Jupiter, but has several times its mass. It's actually so far the smallest planet that's ever been directly imaged with a telescope, rather than being observed by eclipsing its parent star.
The galaxy has a diameter of around 100,000 light years, making it about the size of the Milky Way. Notably, six observed supernovae exist within Messier 61, placing it in a group of galaxies which includes Messier 83, also with six supernovae observed, and NGC 6946, having nine observed supernovae. Messier 61 makes up part of the Virgo Galaxy Cluster, a massive group of galaxies in the constellation of Virgo (the Virgin).