| They came from outer space--and you can have one! Genuine meteorites are now on sale in the Space Weather Store. | | |
POLAR STORM WARNING: Two CMEs are heading for Earth. The plasma clouds were expelled from the sun on August 20-21 by a pair of erupting magnetic filaments. NOAA forecasters expect the CMEs to arrive on August 23-24, possibly sparking geomagnetic storms around the poles.
Aurora alerts: text,
voice.
ANOTHER SUNDIVING COMET: Here we go again. Another comet is diving into the sun, the second one this week. Coronagraphs onboard the Solar and Heliospheric Observatory (SOHO) are monitoring the death plunge:
The icy comet, which probably measures a few 10s of meters wide, is vaporizing furiously and is not expected to survive much longer.
Like the comet that came before it, this one is a member of the Kreutz family. Kreutz sungrazers are fragments from the breakup of a single giant comet many centuries ago. They get their name from 19th century German astronomer Heinrich Kreutz, who studied them in detail.
Because of their common parentage, sungrazers often come in clusters. After today's sungrazer evaporates, it wouldn't be surprising to find yet another in the offing. Stay tuned.
AURORA SEASON BEGINS: Around the Arctic Circle, summer is long and bright. Auroras vanish in the glow of the midnight sun. News flash: the auroras are back. "Tonight I saw the first auroras of the new season in Oulu, Finland," says Thomas Kast, who took this picture on August 22nd:
"This is how the sky looked at ten minutes past midnight," says Kast. "The orange color on the left is twilight, just between sunset and sunrise, and the waves of the Baltic Sea were lit up by the Full Moon. Above it all were some surprisingly strong Northern lights. I saw needles, purple color, and even a very faint corona."
With autumn approaching, Arctic nights are rapidly darkening. This means more auroras are in the offing. NOAA forecasters estimate a 30% - 45% chance of polar geomagnetic storms on August 22 - 23.
Says Kast: "What a promising start!"
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 August 24, 2013 there were 1421 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters: | Asteroid | Date(UT) | Miss Distance | Size |
| 1999 CF9 | Aug 23 | 24.7 LD | 1.1 km |
| 2013 QR1 | Aug 25 | 8.2 LD | 215 m |
| 2002 JR9 | Aug 31 | 63.5 LD | 1.4 km |
| 2013 PX6 | Sep 21 | 68.6 LD | 1.0 km |
| 2000 DK79 | Nov 10 | 49.1 LD | 3.2 km |
| 2011 JY1 | Nov 13 | 8.2 LD | 57 m |
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 |
end quote from: http://spaceweather.com/
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