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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 420.9 km/sec
density: 1.4 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: B9
1652 UT Aug25
24-hr: B9
1652 UT Aug25
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 25 Aug 11
A new sunspot is emerging at the circled location. Credit: SDO/HMI
Sunspot number: 75
What is the sunspot number?
Updated 24 Aug 2011

Spotless Days
Current Stretch: 0 days
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 821 days
Typical Solar Min: 486 days

Updated 24 Aug 2011


The Radio Sun
10.7 cm flux: 104 sfu
explanation | more data
Updated 24 Aug 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 3.1 nT
Bz: 1.4 nT north
explanation | more data
Updated: Today at 2344 UT
Coronal Holes: 25 Aug 11
A solar wind stream flowing from the indicated coronal hole should reach Earth on Aug. 28-29. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Aug 25 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
10 %
10 %
CLASS X
01 %
01 %
Geomagnetic Storms:
Probabilities for significant disturbances in Earth's magnetic field are given for three activity levels: active, minor storm, severe storm
Updated at: 2011 Aug 25 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
 
Thursday, Aug. 25, 2011
What's up in space
 

Are we alone? Your iPhone has the answer. Download the all-new Drake Equation app to calculate the population of the Milky Way.

 
DrakeEQ for iPhone and iPad

SUNSPOT BREAKTHROUGH: A new breakthrough in sunspot detection could provide days of extra early warning for strong solar storms. Get the full story from Science@NASA.

AURORA OUTBURST: Sometimes it pays to wait. "I watched the sky for three hours last night (Aug. 24-25) hoping to see some auroras," says Frank Olsen of Stø, Norway. "I was about to give up when the sky erupted in color." The 10-minute outburst was bright enough to shine through twilight and lunar glare:

"Boy was I happy I hadn't gone home," says Olsen.

The display was caused by a thin but surprisingly effective solar wind stream which has been gently buffeting Earth's magnetic field for the past two days. NOAA forecasters estimate a 15% chance of continued geomagnetic activity tonight; high-latitude sky watchers should remain (patiently) alert for auroras. Aurora alerts: text, voice.

more images: from Bjarki Mikkelsen of Jokkmokk Porjus, Lapland, Sweden; from Sean M. Scully of Akureyri, Iceland

August 2011 Aurora Gallery
[previous Augusts: 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002]

VOLCANIC SUNSETS: Sky watchers in Europe should be alert for volcanic sunsets. "For the past week, we've seen unusual twilight rays probably caused by high-attitude aerosols from Nabro, a volcano which erupted in Eritrea on June 13th," reports Petr Horalek from the Ondřejov Observatory of the Astronomical Institute of the Academy of Sciences of the Czech Republic. This is how the sky looked on Aug. 23rd:

"Around 20 minutes after sunset these significant crepuscular rays appeared like shining fingers in the western sky," he describes. "The rays were so strong, I could see them almost directly overhead; and in the south, they stretched across the horizon like great red and purple stripes."

Purple is one of the telltale colors of a volcanic sunset. Fine volcanic aerosols in the stratosphere scatter blue light which, when mixed with ordinary sunset red, produces a violet hue. Another set of photos taken by Martin Popek in the Czech city of Nýdek highlights the purple signature.

more images: from Monika Landy-Gyebnar of Veszprem, Hungary


2011 Noctilucent Cloud Gallery
[previous years: 2003, 2004, 2005, 2006, 2007, 2008, 2009]

  Near Earth Asteroids
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 25, 2011 there were 1241 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2009 AV
Aug 22
49.7 LD
--
1.1 km
2003 QC10
Sep 18
50 LD
--
1.2 km
2004 SV55
Sep 19
67.5 LD
--
1.2 km
2007 TD
Sep 23
3.8 LD
--
58 m
2002 AG29
Oct 9
77.1 LD
--
1.0 km
2000 OJ8
Oct 13
49.8 LD
--
2.5 km
2009 TM8
Oct 17
1.1 LD
--
8 m
2011 FZ2
Nov 7
75.9 LD
--
1.6 km
2005 YU55
Nov 8
0.8 LD
--
175 m
1994 CK1
Nov 16
68.8 LD
--
1.5 km
1996 FG3
Nov 23
39.5 LD
--
1.1 km
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.
  Essential web links
NOAA Space Weather Prediction Center
  The official U.S. government space weather bureau
Atmospheric Optics
  The first place to look for information about sundogs, pillars, rainbows and related phenomena.
Solar Dynamics Observatory
  Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever.
STEREO
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Solar and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
Daily Sunspot Summaries
  from the NOAA Space Environment Center
Heliophysics
  the underlying science of space weather
Science Central
 
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