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.
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STORM WARNING: A fast-moving stream of solar wind is buffeting Earth's magnetic field. The combined effect of this stream plus a CME expected to arrive soon (see below) has prompted NOAA forecasters to declare a 30% to 35% chance of geomagnetic storms on June 23-24. High-latitude sky watchers should be alert for auroras.
CME FORECAST, REVISED: A CME propelled toward Earth by the "solstice solar flare" of June 21st may be moving slower than originally thought. Analysts at the GSFC Space Weather Lab have downgraded the cloud's probable speed from 800 km/s to 650 km/s. Impact is now expected on June 24th at 0700 UT plus or minus 7 hours. In this animated forecast model, the yellow dot is Earth:
A slower CME should deliver a weaker blow to Earth's magnetic field. Forecasters now predict a relatively mild G1-class (Kp=5) geomagnetic storm when the cloud arrives. High-latitude sky watchers should be alert for auroras during the early hours of June 24. The season favors observers in the southern hemisphere where solstice skies are winter-dark. Aurora alerts: text, voice.
June 2011 Aurora Gallery
[Aurora alerts: text, voice] [previous Junes: 2010, 2008, 2001]
SOLSTICE SOLARGRAPHS: Last December, the staff of the Philippus Lansbergen Observatory in Middelburg, the Netherlands, invited members of the general public to join them for a solargraph-making party. A solargraph is a simple pinhole camera made from a soda or beer can lined with a piece of photographic paper. About a 100 cans were deployed around the observatory and, six months later, here are the results:
Each blue square shows the daily path of the sun across the skies of the Netherlands. The lowest arcs were traced by the winter sun of Dec. 2010. The highest arc was made by the sun just yesterday, June 19th, only two days before the 2011 summer solstice. Occasional gaps are caused by clouds.
"As you can see," says a member of the observatory staff, "we had one of the sunniest springs ever in our province. It was even sunnier than in southern Spain!"
6-month Solargraph How-to Guides: #1, #2, #3
June 15th Lunar Eclipse Gallery
Midnight Solar Eclipse Gallery
[NASA: A Rare Eclipse of the Midnight Sun]
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 June 23, 2011 there were 1224 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 |