The High Resolution Imaging Science Experiment (HiRISE), orbiting the red planet on the Mars Reconnaissance Orbiter, snapped an image of large rocks on the floor of an impact crater in an image released April 10.
The fragmented rocks, greater than three feet (one meter) across, are mixed in with smaller, fine-grained particles. This type of mix is called megabreccia, and usually results from impact events like a meteor hitting a planet.
Image courtesy U. Arizona/NASA
Ghostly Green Shroud
The final death throes of a dying star in the constellation Scutum (the Shield) produce a glowing shroud in this picture released April 10 by the European Southern Observatory. The cloud of gas, called planetary nebula IC 1295, is located 3,300 light-years away.
When stars the size of our sun fade away, they don't go quietly. During the final phase of a star's demise, unstable fusion reactions in its core blow its atmosphere into space. Radiation from the star interacts with the gas, causing the whole thing to glow. (Learn about the life cycle of stars.)
Image courtesy ESO
The ruins of a desert castle stand guard near the town of Kashan (map), Iran, in a picture taken March 16.
The Milky Way galaxy marches across the sky while airglow—light emanating from Earth's atmosphere—paints the night with pale greens and purples.