Discovered in 1784 by William Herschel, NGC 4394 is the archetypal barred spiral galaxy, with bright spiral arms emerging from the ends of a bar that cuts through the galaxy’s central bulge. Some 55 million light-years from Earth, the galaxy lies in the constellation of Coma Berenices. NGC 4394 is considered to be a member of the Virgo Cluster.
On Monday, 9 May there will be a rare transit of Mercury, when the innermost planet in our solar system will pass directly between the Earth and the Sun. The last time this happened was in 2006. With a properly filtered telescope and fine weather, the entire 7½-hour event can be seen from the British Isles.