Image description: Though it may resemble a giant mechanical mushroom, the device these scientists are working on is an inflatable heat shield to slow and protect spacecraft as they blaze through the atmosphere at hypersonic speeds. When deflated, the 10-foot shield can be packed into a 22-inch diameter rocket.

NASA will test the heat shield with a launch early in the morning on Saturday, July 21. Watch it live.

Photo by NASA.

Image description: A team of astronomers using NASA’s Hubble Space Telescope is reporting the discovery of another moon orbiting the icy dwarf planet Pluto. The moon is estimated to be irregular in shape and 6 to 15 miles across. Learn more about the discovery.

Image from NASA; ESA; M. Showalter, SETI Institute

Image description: Venus passing across the face of the sun, producing a silhouette that no one alive today will likely see again.

Watch NASA’s live coverage of the Transit of Venus.

Image from NASA’s Astronomy Picture of the Day.

Image description: The SpaceX Dragon commercial cargo craft approaches the International Space Station on May 24, 2012 for a series of tests to clear it for its final rendezvous and grapple on May 25.

The SpaceX Dragon capsule, which on Tuesday became the first commercially developed and built spacecraft to launch to the International Space Station, is carrying among its cargo a suite of 15 science experiments designed by students.

Learn more about SpaceX from NASA.

Image description: This artist concept of the local galaxy Arp 220, captured by the Hubble Space Telescope, shows that galaxies with the most powerful, active, supermassive black holes at their cores produce fewer stars than galaxies with less ones. Learn more about how active black holes squash star formation.

Image courtesy of NASA/JPL-Caltech