Streaks in Snapchat is a feature that tracks how many days in a row you and a friend have snapped each other — but who has the world’s longest streak? Streaks are established when two users ...

The first image of H335H shows the glass side of the photographic plate, on which Hubble marked novae and, eventually, the first Cepheid in ink. The next two images show the emulsion side of the plate ...