On June 5th or 6th (depending on where you are in the world) Venus will pass directly between the Sun and the Earth, so it’s basically a solar eclipse, but with Venus instead of the Moon. Unless you’re taking some seriously awesome vitamins, you probably won’t live to see the next transit in 2117. It begins around 22:00 June 5th UTC and will continue until about 5:00 June 6th UTC. Exoplaneteers have been trying to read the composition of the atmospheres of planets around other stars when those planets transit by looking at the light that filters through their atmospheres. By looking at the light filtering through Venus’ atmosphere they’ll be able to double-check their technique.