Metallic photos of the sun by renowned photographer Greg Piepol bring together the best of art and science. Buy one or a whole set. They make a stellar gift. | | | SPRING IS FIREBALL SEASON: For reasons researchers do not understand, the rate of midnight fireballs increases during the weeks around the vernal equinox. It's a beautiful display, but where do they come from? NASA's growing network of fireball cameras is scanning the heavens for answers: full story. MORNING SKY SHOW: Dawn is a beautiful time to be awake. It was extra-beautiful this morning thanks to a sunrise conjunction between Venus and the crescent Moon. Azhy Hasan sends this picture from Arbil city in the Kurdistan Region of Iraq: "It was wonderful!" says Hasan. "Seeing these two bright lights in the dawn sky was a great way to start the day." more images: from Stefano De Rosa of La Morra, Italy; from Monika Landy-Gyebnar of Veszprem, Hungary; from Jim Werle of Las Vegas, Nevada; from Kevin Jung of Lowell Township, Michigan; from Michael Boschat of Halifax,Nova Scotia,Canada UNDER THE WILD GRASS: Yesterday in Michigan, Kevin Jung laid down among the wild spring grass, pointed his camera toward the sky, and--snap!--recorded a luminous ring around the sun: "It was a really nice sun halo," he says. "The grass blocked the glare so I could photograph it using my Canon DLSR." Sun haloes are caused by ice crystals in high cirrus clouds, and they can be very photogenic. So, photographers, when wispy clouds drift across the sun, you know what to do: grab your camera and dive into the wild grass. Potentially Hazardous Asteroids ( PHAs) are space rocks larger than approximately 100m that can come closer to Earth than 0.05 AU. None of the known PHAs is on a collision course with our planet, although astronomers are finding new ones all the time. On March 31, 2011 there were 1215 potentially hazardous asteroids. Notes: LD means "Lunar Distance." 1 LD = 384,401 km, the distance between Earth and the Moon. 1 LD also equals 0.00256 AU. MAG is the visual magnitude of the asteroid on the date of closest approach. | The official U.S. government space weather bureau | | The first place to look for information about sundogs, pillars, rainbows and related phenomena. | | Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever. | | 3D views of the sun from NASA's Solar and Terrestrial Relations Observatory | | Realtime and archival images of the Sun from SOHO. | | from the NOAA Space Environment Center | | the underlying science of space weather | | for out-of-this-world printing and graphics | |