These pictures are almost too hot to touch. Metallic photos of the sun make great Christmas gifts. | | | QUIET HOLIDAY: The Earth-side of the sun is blank--no sunspots--and solar activity is very low. Geomagnetic storms are unlikely between now and Christmas. BRIGHT LUNAR ECLIPSE: Yesterday's solstice lunar eclipse turned the Moon a bright shade of red--a fact with implications for terrestrial climate. More on that below, but first, regard the lunar landscape photographed during totality by Jimmy Westlake near Dublin, Georgia: "The combination of blues and reds at the onset of totality was simply beautiful," says Westlake. "I took the picture using a Nikon D700 digital camera with a 11-inch Celestron telescope." The luminosity of the eclipse reveals much about the state of Earth's upper atmosphere. University of Colorado Prof. Richard Keen explains: "At the distance of the Moon, most of the light refracted into Earth's shadow passes through the stratosphere. When the stratosphere is clear (not 'dirtied' by volcanic aerosols) the shadow and therefore the eclipsed Moon is relatively bright." Keen observed the eclipse on Dec. 21st and was able to draw some conclusions. "Using an 8x reversed monocular, I estimated the visual magnitude of the eclipsed moon at mid-totality as -1.9. This compares with a 'clear stratosphere' value of -2.1 to give a volcanic aerosol optical depth of 0.004--essentially zero. The stratosphere remains clear." This is timely and important because the state of the stratosphere affects climate; a clear stratosphere "lets the sunshine in" to warm the Earth below. Yesterday's bright eclipse reinforces a conclusion Keen reported at the SORCE conference in 2008: "The lunar eclipse record indicates a clear stratosphere over the past decade, and that this has contributed about 0.2 degrees to recent warming." UPDATED: 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 22, 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 | |