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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 366.7 km/sec
density: 2.2 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: C2
2116 UT Nov21
24-hr: M3
1530 UT Nov21
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 21 Nov 12
Sunspot AR1618 has a beta-gamma magnetic field that harbors energy for M-class solar flares. Credit: SDO/HMI
Sunspot number: 119
What is the sunspot number?
Updated 21 Nov 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 21 Nov 2012


The Radio Sun
10.7 cm flux: 141 sfu
explanation | more data
Updated 21 Nov 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 3
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 3.1 nT
Bz: 2 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 21 Nov 12
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2012 Nov 21 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
70 %
70 %
CLASS X
30 %
30 %
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 Nov 21 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
35 %
MINOR
05 %
30 %
SEVERE
01 %
10 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
10 %
MINOR
30 %
20 %
SEVERE
25 %
65 %
 
Wednesday, Nov. 21, 2012
What's up in space
 

Hang the Transit of Venus on your wall! Hubble-quality images from NASA's Solar Dynamics Observatory are now available as metallic posters in the Space Weather Store.

 
Venus Transit metal posters

SOLAR WIND: A medium-speed (~425 km/s) stream of solar wind is buffeting Earth's magnetic field. The solar wind is not blowing hard enough to ignite a full-fledged geomagnetic storm, but it is stirring up some beautiful auroras around the Arctic Circle. Check the realtime aurora gallery for latest images.

M-CLASS SOLAR FLARES: The magnetic canopy of big sunspot AR1618 is crackling with M-class solar flares. This image taken by NASA's Solar Dynamics Observatory shows the extreme ultraviolet flash from one of them, an M1.6-class flare on Nov. 20th at 1928 UT:

This eruption, and another one like it about 7 hours earlier, might have propelled faint coronal mass ejections (CMEs) toward Earth. If so, the impacts would likely commence on Nov. 23rd, with a chance of high-latitude geomagnetic storms following their arrival. Stay tuned for updates. Aurora alerts: text, voice.

FAST-GROWING SUNSPOT (Updated Nov. 21): Only a few days ago, sunspot AR1618 was almost invisible. Now it is a behemoth more than 10 times wider than Earth. A movie from NASA's Solar Dynamics Observatory shows the sunspot's development on Nov. 20-21:

As the sunspot evolves, so does its intense magnetic field--and this means strong flares are in the offing. Fast-changing magnetic fields on the sun have a tendency to reconnect and erupt. NOAA forecasters estimate a 70% chance of M-class flares and a 15% chance of X-flares during the next 24 hours. Because of the sunspot's nearly central location on the solar disk, any eruptions will likely be Earth-directed. Solar flare alerts: text, voice.

Realtime Space Weather Photo Gallery

INSIDE THE SHADOW OF THE MOON: On Nov. 13/14, the Moon passed directly i front of the sun. This arrangement, which produced a total eclipse, cast the shadow of the Moon directly down on northeast Australia. Using a wide-field camera, eclipse-chaser Alan Dyer photographed the shadow as it raced across the sky over Lakeland Downs, Queensland. Scan the images, then read Dyer's account of the shadow-transit below:

"This collage of wide-angle shots shows the motion of the Moon's conical shadow," he explains. "At top, you can see the bottom edge of the shadow just touching the Sun. This was second contact and the diamond ring effect that begins totality. The middle frame was taken near mid-eclipse and shows the bright horizon beyond the Moons shadow. However, the Sun is not centered on the shadow because we were located well north of the eclipse's center-line, where we had gone to escape nearby clouds. The bottom frame was taken at the end of totality as the first bit of sunlight bursts out from behind the Moon. Notice the sun sitting at the well-defined left edge of the Moon's shadow. The shadow moved off to the right."

People who have experienced total eclipses first-hand say the Moon's shadow is one of the most amazing aspects of the experience. Its arrival causes many birds to stop singing; a hush descends on the landscape as the sky darkens and the air temperature suddenly drops. The Moon's shadow lances more than a quarter million miles across the silent vacuum of space, and when it lands on Earth, it seems to bring a bit of otherworldly cold with it.

For more otherworldly images of the eclipse, browse the gallery:

Realtime Eclipse 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 November 21, 2012 there were 1353 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Size
2012 VS76
Nov 16
2.4 LD
18 m
2012 VU76
Nov 16
8.1 LD
33 m
2012 VB26
Nov 17
9.7 LD
34 m
2012 VE77
Nov 18
4.5 LD
24 m
2012 VN76
Nov 20
7.3 LD
13 m
2010 JK1
Nov 25
9.3 LD
56 m
2009 LS
Nov 28
55.2 LD
1.1 km
2012 WH1
Nov 29
7.6 LD
81 m
2009 BS5
Dec 11
8.4 LD
15 m
4179 Toutatis
Dec 12
18 LD
2.7 km
2003 SD220
Dec 23
59.8 LD
1.8 km
1998 WT24
Dec 23
69.2 LD
1.1 km
2003 UC20
Dec 29
25.7 LD
1.0 km
1999 HA2
Feb 5
58 LD
1.3 km
3752 Camillo
Feb 12
57.5 LD
3.4 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.
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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