The Supernova You Were Never Supposed to See
The star had been in hiding. A galaxy sat halfway between it and us, eclipsing it from the Earth's point of view. But when it went supernova last September, astronomers caught the image of the concealed explosion anyhow, all thanks to a cool trick of physics. Because of a bizarre effect called gravitational lensing explained by Einstein's theory of general relativity, scientists caught four separate images of the supernova in a single picture.