Fifty-one Perseid meteors were captured in this composite image of 30-second exposures taken over six hours in 2004. The annual Perseid meteor shower is one of the most visible to the human eye.
A new study shows energy output from 200,000 galaxies is half what it was billions of years ago. It's further evidence the universe is slowly declining. This undated NASA Hubble Space Telescope image shows the spiral galaxy NGC 1512 captured in all wavelengths from ultraviolet to infrared.
The SpaceX Falcon 9 rocket and Dragon spacecraft break apart shortly after liftoff from the Cape Canaveral Air Force Station in Cape Canaveral, Fla., on June 28. SpaceX CEO Elon Musk said Monday the failure of a steel strut likely caused the rocket to explode.
An image of Europa released by the Jet Propulsion Laboratory in Pasadena, Calif., in 1996 by the Galileo spacecraft. NASA says a new probe dedicated to studying the Jovian moon, is going into the development phase.
European Space Agency astronaut Samantha Cristoforetti of Italy checks her Sokol pressure suit aboard the International Space Station. Cristoforetti, who set an endurance record, is among three astronauts who returned on Thursday.
Computer modeling illustrations of Pluto's moon Nix demonstrate that its orientation changes unpredictably as it orbits the "double planet" of Pluto and Charon.
M. Showalter (SETI)/G. Bacon (STScI)/NASA/ESA