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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 380.5 km/sec
density: 3.4 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: B1
2100 UT Aug12
24-hr: B3
1306 UT Aug12
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 12 Aug 11
None of these small sunspots poses a threat for strong flares. Credit: SDO/HMI
Sunspot number: 36
What is the sunspot number?
Updated 11 Aug 2011

Spotless Days
Current Stretch: 0 days
2011 total: 1 day (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 820 days
Typical Solar Min: 486 days

Updated 11 Aug 2011

The Radio Sun
10.7 cm flux: 84 sfu
explanation | more data
Updated 11 Aug 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 2.2 nT
Bz: 1.7 nT south
explanation | more data
Updated: Today at 2344 UT
Coronal Holes: 12 Aug 11
Solar wind flowing from the indicated coronal should reach Earth on or about Aug. 15th. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Aug 12 2200 UTC
0-24 hr
24-48 hr
01 %
01 %
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 12 2200 UTC
0-24 hr
24-48 hr
25 %
40 %
05 %
10 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
25 %
40 %
10 %
15 %
01 %
05 %
Friday, Aug. 12, 2011
What's up in space

They came from outer space--and you can have one! Genuine meteorites are now on sale in the Space Weather Store.

Own your own meteorite

PERSEID METEOR SHOWER: Earth is entering a stream of debris from Comet Swift-Tuttle, source of the annual Perseid meteor shower. International observers are now reporting more than 20 Perseids per hour, a number that will increase as the shower reaches its peak on August 12-13.

"Last night I witnessed a large and colorful Perseid over my home in Silkeborg, Denmark," reports photographer Jesper Grønne. A close-up of the meteor shows its vivid color.

John Chumack of Dayton, Ohio, adds this report: "Last night between 10 pm and 6 am I recorded more than 100 meteors using various sky cameras mounted on top of my home and backyard observatory. Moonlight is not preventing us from seeing the bright ones!" He compiled a timelapse slideshow of highlights. "Note how my dome rotates during the observing session," he points out.

The best time to look is Saturday morning, Aug. 13, just before dawn when the Moon is low and meteor rates are peaking. Some observers will also see the International Space Station, which coincidentally flies over many US towns and cities during the shower's peak: ISS tracker. Also, be sure to tune into Space Weather Radio to hear the ghostly pings of Perseids disintegrating over the US Air Force's Space Surveillance Radar. It makes a great soundtrack for any meteor watch.

What sat was that? The hours before dawn are a great time to see satellites. There are hundreds in Earth orbit, and you're sure to spot some of them while you're watching the Perseids. Your Android phone can tell you which ones you're seeing: Download WhatSat.

more Perseid images: from David Blanchard of Flagstaff, Arizona; from Marco Langbroek of Leiden, the Netherlands; from Aaron Top of Shallow Lake Ontario Canada; from Torcuill Torrance of Stonehaven, Scotland, UK

PARTING SHOTS: Active sunspot 1263, which just two days ago produced the most powerful solar flare of the new Solar Cycle (an X7), has left the Earthside of the sun. It is now beginning a two week transit across the solar farside. We can still see signs of its ongoing activity, however. On August 11th, an eruption from sunspot 1263 hurled a bright CME over the sun's western limb:

For the next two weeks (the time it takes to transit the sun's farside) no blasts from sunspot 1063 will be Earth directed. For the next few days, however, we could see a few more parting shots. Readers with solar telescopes are encouraged to monitor developments.

TODAY'S BONUS SHOTS: Flying Spectrum from Dave Eagle of Higham Ferrers, England; Michigan Auroras from T. Scott Blankinship of Paradise, Michigan; Dark Rays from Ugur Ikizler of Mudanya - Bursa / Turkey; Striped Sunset from Marie Hall of Bridgeport, Ny

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

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 12, 2011 there were 1241 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 PE2
Jul 30
3.5 LD
108 m
2011 OJ45
Aug 17
4.6 LD
28 m
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
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.
  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
  the underlying science of space weather
Science Central
Conquest Graphics
  for out-of-this-world printing and graphics
Trade Show Displays
  more links...
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