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They came from outer space--and you can have one! Genuine meteorites are now on sale in the Space Weather Store. |
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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.
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The
official U.S. government space weather bureau |
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The
first place to look for information about sundogs,
pillars, rainbows and related phenomena. |
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Researchers
call it a "Hubble for the sun." SDO
is the most advanced solar observatory ever. |
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3D
views of the sun from NASA's Solar and Terrestrial
Relations Observatory |
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Realtime
and archival images of the Sun from SOHO. |
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from
the NOAA Space Environment Center |
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the
underlying science of space weather |
end quote from: http://spaceweather.com/
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