Turn your cell phone into a field-tested satellite tracker. Works for Android and iPhone. | | | EMERGING SUNSPOTS: The quiet sun is suddenly active again with sunspots breaking through the stellar surface at three locations. Readers with solar telescopes should point their optics here. sunspot images: from Michael Buxton of Ocean Beach, California; from Gianfranco Meregalli of Milano Italy; from Howard Eskildsen of Ocala, Florida; from Cai-Uso Wohler of Bispingen, Germany; SINUOUS AURORAS: US Department of Defense polar-orbiting satellites are observing bright bands of auroral light circling the North Pole. This display, recorded on Dec. 30th, was as bright as the city lights of Scandinavia below: Paul McCrone of the Fleet Numerical Meteorology and Oceanography Center in Monterey, CA, assembled the image using visual and infrared data from three satellites: DMSP F13, F17 and F18. "It shows the sinuous path of the energetic particles entering Earth's upper atmosphere," he says. These sinuous bands could descend south over Europe and parts of North America around Jan. 3rd when a solar wind stream is expected to hit Earth's magnetosphere. High-latitude sky watchers should be alert for auroras. GIANT STORM ON SATURN: Got a telescope for Christmas? Point it at Saturn. A giant storm even brighter than Saturn's rings is raging through the planet's cloudtops. "I've never seen anything like this," says veteran planetary photographer Anthony Wesley. "It's possible that this is the biggest storm on Saturn in many decades." Here it is recorded by Wesley's 16-inch telescope on Dec. 22nd: Instruments on NASA's Cassini spacecraft are picking up strong bursts of radio static. Apparently, lightning is being generated in multiple cells across the storm front. Cassini's cameras are also beaming back fantastic images of the tempest. "At it's current size and brightness, the storm should be visible to anyone with a mid-size scope under steady seeing," continues Wesley. "This is a great time to be a planetary photographer." [Sky maps: Dec. 29, 30, 31] more images: from Fredy Willems of Waipahu, Hawaii; from Glenn Jolly of Gilbert, Arizona; from Christopher Go of Cebu City, Philippines; from Sadegh Ghomizadeh of Tehran, Iran; from Vincent Lao of Pasig City, Philippines Lunar Eclipse Photo Gallery [NASA: "Solstice Lunar Eclipse"] [astronomy alerts] November 2010 Aurora Gallery [previous Novembers: 2009, 2008, 2007, 2006, 2004, 2003, 2002, 2001, 2000] 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 December 31, 2010 there were 1167 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 | |