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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 412.3 km/sec
density: 2.3 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: B6
1934 UT Dec21
24-hr: B6
0613 UT Dec21
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 21 Dec 12
None of the spots on the Earthside of the sun is actively flaring. Credit: SDO/HMI
Sunspot number: 53
What is the sunspot number?
Updated 20 Dec 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 20 Dec 2012

The Radio Sun
10.7 cm flux: 113 sfu
explanation | more data
Updated 20 Dec 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 2.2 nT
Bz: 0.1 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 20 Dec 12
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2012 Dec 21 2200 UTC
0-24 hr
24-48 hr
05 %
05 %
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: 2012 Dec 21 2200 UTC
0-24 hr
24-48 hr
05 %
10 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
10 %
20 %
05 %
10 %
Friday, Dec. 21, 2012
What's up in space

Thirty-five new items have just been added to our Meteorite Jewelry collection. Browse the Space Weather Store for something out of this world.

Meteorite jewelry

DEC 21st TRANSIT OF VENUS: Today, researchers are using NASA's Cassini spacecraft to observe a rare transit of Venus visible from the planet Saturn. Get the full story from Science@NASA.

WILL THERE BE A DECEMBER 22ND? NASA says yes. The space agency is so sure that the world will not end due to a Mayan Apocalypse on Dec. 21, 2012, that they've already produced a video about the day after: Why the World Didn't End Yesterday

FARSIDE SOLAR ACTIVITY: The Earthside of the sun remains quiet, but the farside is growing restless. During the late hours of Dec. 20th and continuing through Dec. 21st, the Solar and Heliospheric Observatory (SOHO) has recorded a series of CMEs flying over the solar limb:

The source of the clouds appears to be multiple blast sites on the farside of the sun. This means Earth is not in the line of fire. The increasing pace of farside activity, however, suggests that the Earthside might not be far behind. Stay tuned for changes. Solar flare alerts: text, voice.

Realtime Space Weather Photo Gallery

SIX MONTHS IN A SODA CAN: "Winter solstice is coming!" says Rijk-Jan Koppejan of the Philippus Lansbergen Observatory in Middelburg, the Netherlands. To celebrate, patrons of the observatory have started opening their solargraphs, which they deployed six months ago to record the motion of the sun. "This image with the typical Dutch windmill was made by the Sengers family," says Koppejan:

A solargraph is a simple pinhole camera made from a soda can lined with a piece of photographic paper. "Last June, the Philippus Lansbergen Observatory invited people to hang up solargraphs around the province of Zeeland," he explains. "They have recorded the daily path of the sun since the summer solstice."

In a typical six-month solargraph exposure, high arcs track the summer sun, middle arcs the autumn sun, and low arcs the winter sun. The only interruptions are due to clouds and rain. "The weather in Middelburg wasn't too bad after all!"

Most of the solargraphs deployed last June will be opened on Friday the 21st, the northern winter solstice. Stay tuned.

6-month Solargraph How-to Guides: #1, #2, #3

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 December 21, 2012 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2012 XM16
Dec 16
3.1 LD
31 m
2003 SD220
Dec 23
59.8 LD
1.8 km
1998 WT24
Dec 23
69.2 LD
1.1 km
2012 XM55
Dec 23
3 LD
12 m
2012 XP55
Dec 27
9.1 LD
68 m
1999 HA2
Feb 5
58 LD
1.3 km
3752 Camillo
Feb 12
57.5 LD
3.4 km
1999 YK5
Feb 15
49.1 LD
2.1 km
2012 DA14
Feb 15
0.09 LD
57 m
2009 AV
Feb 25
59.7 LD
1.0 km
2007 EO88
Mar 18
4.4 LD
23 m
1993 UC
Mar 20
49 LD
3.8 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
Space Weather Alerts
  more links...
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