This is an artist's concept of the tiny moon Hippocamp that was discovered by the Hubble Space Telescope in 2013. Only 20 miles across, it may actually be a broken-off fragment from a much larger neighboring moon, Proteus, seen as a crescent in the background. This is the first evidence for a moon being an offshoot from a comet collision with a much larger parent body. Credit: NASA, ESA and J. Olmsted (STScI)

Astronomers combined observations from three different observatories (Atacama Large Millimeter/submillimeter Array, red; Hubble, green; Chandra X-ray Observatory, blue) to produce this colorful, multiwavelength image of the intricate remains of Supernova 1987A. Credits: NASA, ESA, and A. Angelich (NRAO/AUI/NSF)