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Solar wind
speed: 457.8 km/sec
density: 4.8 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: C2
2237 UT May21
24-hr: C2
2237 UT May21
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 21 May 13
Sunspot AR1748 has quieted since it unleashed four X-flares last week. Nevertheless, it still has a delta-class magnetic field that harbors energy for strong explosions. Credit: SDO/HMI
Sunspot number: 113
What is the sunspot number?
Updated 21 May 2013

Spotless Days
Current Stretch: 0 days
2013 total: 0 days (0%)
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
21 May 2013

The Radio Sun
10.7 cm flux: 132 sfu
explanation | more data
Updated 21 May 2013

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: 3.7 nT
Bz: 1.6 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 20 May 13
Solar wind flowing from this coronal hole should reach Earth on May 23-24. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2013 May 21 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
50 %
50 %
CLASS X
20 %
20 %
Geomagnetic Storms:
Probabilities for significant disturbances in Earth's magnetic field are given for three activity levels: active, minor storm, severe storm
Updated at: 2013 May 21 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
30 %
MINOR
05 %
10 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
25 %
30 %
SEVERE
30 %
40 %
 
Tuesday, May. 21, 2013
What's up in space
 

Listen to radar echoes from satellites and meteors, live on listener-supported Space Weather Radio.

 
Spaceweather Radio is on the air

BRIGHT EXPLOSION ON THE MOON: Recently, a small boulder hit the Moon and exploded with as much energy as 5 tons of TNT. NASA scientists say the explosion was bright enough to see with the naked eye. [full story] [video]

A BIG ASTEROID APPROACHES: Near-Earth asteroid 1998 QE2 is approaching the Earth-Moon system for a flyby on May 31st. There's no danger of a collision; at closest approach the asteroid will be 3.6 million miles away. Even at that distance, however, the 1.7-mile-wide space rock will be an easy target for mid-sized backyard telescopes. Using a 14-inch Celestron, Alberto Quijano Vodniza of Narino, Colombia took this picture of 1998 QE2 on May 17th:

The sunlit side of the asteroid will turn more squarely toward Earth during the first week of June. At that time it will reach a maximum brightness of 11th magnitude.

NASA radars will be monitoring the flyby, too. "Asteroid 1998 QE2 will be an outstanding radar imaging target at Goldstone and Arecibo and we expect to obtain a series of high-resolution images that could reveal a wealth of surface features," says radar astronomer Lance Benner of JPL. "Whenever an asteroid approaches this closely, it provides an important scientific opportunity to study it in detail to understand its size, shape, rotation, surface features, and what they can tell us about its origin."

Stay tuned for updates and observing tips.

Realtime Space Weather Photo Gallery

WEEKEND CME STRIKES: Over the weekend, a pair of CMEs hit Earth--one on May 18th (0100 UT) and another on May 19th (2250 UT). The impacts, especially the first one, rattled Earth's magnetic field and sparked Northern Lights visible as far south as Colorado. Some of the brightest appeared over Cape Cod, Massachusetts, where photographer Chris Cook took this self-portrait:

"This is the first time since September 2005 that the lights have been visible from here," says Cook. " It was a beautiful display. During the peak, which lasted about 20 minutes, I could see red and pink pillars with my unaided eye." With only a short exposure, Cook's camera revealed the true depth of color shown above.

More auroras are possible tonight as Earth's magnetic field continues to reverberate from the impacts. NOAA forecasters estimate a 20% chance of polar geomagnetic storms on May 20th. Aurora alerts: text, voice.

Realtime Aurora Photo Gallery


Realtime Comet 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 May 21, 2013 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Size
2013 JM22
May 16
7.9 LD
95 m
2013 KQ1
May 16
6.6 LD
19 m
2013 KA
May 17
2.1 LD
10 m
2013 KT1
May 21
3.2 LD
22 m
2013 KB
May 22
3.2 LD
16 m
2013 KS1
May 22
4.8 LD
18 m
2004 BV102
May 25
69.9 LD
1.4 km
1998 QE2
May 31
15.2 LD
1.8 km
2009 FE
Jun 4
9.6 LD
230 m
2000 FM10
Jun 5
50.3 LD
1.3 km
2002 KL3
Jun 6
66.4 LD
1.1 km
1999 WC2
Jun 12
39.2 LD
1.9 km
2006 RO36
Jun 18
70.9 LD
1.2 km
2001 PJ9
Jul 17
29.2 LD
1.1 km
2006 BL8
Jul 26
9.3 LD
48 m
2003 DZ15
Jul 29
7.6 LD
153 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.
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
Space Weather Alerts
   
  more links...
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