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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 379.9 km/sec
density: 2.2 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: M1
2254 UT Aug18
24-hr: M5
0102 UT Aug18
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 18 Aug 12
None of the sunspots on the Earthside of the sun pose a threat for strong flares, but a potent farside active region is approaching from just behind the NE limb. Credit: SDO/HMI
Sunspot number: 42
What is the sunspot number?
Updated 18 Aug 2012

Spotless Days
Current Stretch: 0 days
2012 total: 0 days (0%)
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 821 days
Typical Solar Min: 486 days

Update 18 Aug 2012

The Radio Sun
10.7 cm flux: 98 sfu
explanation | more data
Updated 18 Aug 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 4 unsettled
24-hr max: Kp= 4
explanation | more data
Interplanetary Mag. Field
Btotal: 10.8 nT
Bz: 7.8 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 17 Aug 12
A solar wind stream flowing from the indicated coronal hole should reach Earth on ~Aug. 20. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2012 Aug 18 2200 UTC
0-24 hr
24-48 hr
55 %
55 %
05 %
05 %
Geomagnetic Storms:
Probabilities for significant disturbances in Earth's magnetic field are given for three activity levels: active, minor storm, severe storm
Updated at: 2012 Aug 18 2200 UTC
0-24 hr
24-48 hr
20 %
20 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
20 %
30 %
30 %
25 %
25 %
Saturday, Aug. 18, 2012
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

SIGNIFICANT SOLAR FLARE, NOT EARTH-DIRECTED: Magnetic fields snaking over the sun's northeastern limb erupted on August 18th (01:02 UT), producing a significant M5.5-class solar flare. NASA's Solar Dynamics Observatory (SDO) recorded the blast:

The magnetic filament shown erupting above appears to be connected to an active sunspot on the farside of the sun. A great way to see the farside spot is using NASA's 3D Sun app, which shows our star as a 3-dimensional globe that you can spin and inspect from any angle. Download the app and look around the globe for a hot sspot labeled 'farside AR.'That's the farside active region.

Another movie from SDO shows flashes of extreme ultraviolet radiation and plumes of plasma flying over the sun's northeastern limb:

These flares herald the approach of the active region as the sun's rotation turns it in our direction. Soon, it will become an Earthside sunspot group and the eruptions which are missing our planet now could become geoeffective. A significant uptick in solar activity is likely in the days ahead. Solar flare alerts: text, phone.

Realtime Space Weather Photo Gallery

RETURN OF THE ARCTIC AURORAS: It has been a while since sky watchers around the Arctic Circle have enjoyed the Northern Lights. Auroras are hard to see through the glare of the midnight sun. As summer comes to an end, however, aurora season is beginning again. On August 16th, B.Art Braafhart spotted a splash of green over Salla in the Finnish Lapland:

"Finally, after three nights hunting for 'the green lights,' I made the first catch of the new season," says Braafhart. "The nice temperature (+12C) was accompanied by zooming mosquitos around midnight. The apparition was brief, the colors thin and light, but after an absence of 4 months exciting again!" Aurora alerts: text, phone.

Realtime Aurora Photo Gallery

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

  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 18, 2012 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
37655 Illapa
Aug 12
37 LD
1.2 km
2012 PZ17
Aug 12
3 LD
20 m
2012 PD20
Aug 18
9.7 LD
36 m
2000 ET70
Aug 21
58.5 LD
1.1 km
1998 TU3
Aug 25
49.2 LD
4.9 km
2009 AV
Aug 26
62.8 LD
1.1 km
1998 UO1
Oct 4
60.1 LD
2.1 km
2005 GQ21
Oct 12
77 LD
1.0 km
1998 ST49
Oct 18
28.7 LD
1.3 km
1991 VE
Oct 26
34 LD
1.1 km
2001 CV26
Oct 30
68 LD
2.4 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.
  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
Trade Show Displays
  more links...
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