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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 422.3 km/sec
density: 0.2 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: C5
1706 UT Apr18
24-hr: C8
1239 UT Apr18
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 18 Apr 12
Sunspot 1460 is growing rapidly and could soon pose a threat for M-class solar flares. Credit: SDO/HMI
Sunspot number: 78
What is the sunspot number?
Updated 17 Apr 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

Updated 17 Apr 2012


The Radio Sun
10.7 cm flux: 114 sfu
explanation | more data
Updated 17 Apr 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: 3.5 nT
Bz: 0.2 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 18 Apr 12
There are no large coronal holes on tthe Earthside of the sun. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2012 Apr 18 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
15 %
15 %
CLASS X
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 Apr 18 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
25 %
MINOR
01 %
10 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
15 %
30 %
SEVERE
10 %
30 %
 
Wednesday, Apr. 18, 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

UNUSUAL 3D METEOR PHOTO-OP: This weekend, NASA scientists, amateur astronomers, and an astronaut on board the International Space Station will attempt the first-ever 3D photography of meteors from Earth and space. The rare photo-op occurs during the peak of the Lyrid meteor shower. Get the full story from Science@NASA.

ION WAVES IN EARTH'S ATMOSPHERE: Today, a volley of C-class solar flares sent waves of ionization rippling through the atmosphere high over Europe. Dave Gradwell of Birr, Ireland, detected the disturbances using a VLF radio monitoring system:

The source of the flares is a sunspot in the sun's southern hemisphere (tentatively numbered AR1463)--one of several active regions popping up around the solar disk. With sunspot numbers on the rise, more flares and ion waves are likely in the days ahead. Stay tuned. Solar flare alerts: text, voice.

GROWING SUNSPOT: What a difference a day makes. On April 16th, sunspot AR1460 did not exist. Twenty-four hours later it was twice as big as the planet Earth. This April 17th movie from NASA's Solar Dynamics Observatory shows sunspot genesis in action:

The sunspot's magnetic field is still too simple for strong flares, but if the expansion continues apace, instabilities could develop that lead to explosions. Readers with solar telescopes should keep an eye on AR1460.

SPECTACULAR EXPLOSION: Magnetic fields on the sun's northeastern limb erupted around 17:45 UT on April 16th, producing one of the most visually-spectacular explosions in years. NASA's Solar Dynamics Observatory (SDO) recorded the blast at extreme ultraviolet wavelengths:

.

The explosion, which registered M1.7 on the Richter Scale of solar flares, was not Earth-directed, but it did hurl a CME into space. Analysts at the Goddard Space Weather Lab have analyzed the trajectory of the cloud and found that it will hit NASA's STEREO-B spacecraft, the Spitzer space telescope, and the rover Curiosity en route to Mars. Planets Venus and Mars could also receive a glancing blow.

Using data from SDO, Steele Hill of NASA's Goddard Space Flight Center assembled a must-see movie of the event. It shows the explosion unfolding at 304Å, a wavelength which traces plasma with a temperature around 80,000 K.

Coverage of the blast was not limited to space telescopes. Amateur astronomers saw it, too. Jim Lafferty sends this picture from his backyard observatory in Redlands, California:

"Yesterday's prominence on the sun's eastern limb was was one of the largest in years---short lived, it was mostly gone in a few hours," says Lafferty. "It was a wonderful sight in the eyepiece and in the camera!"

more images: from Vahan Yeterian of Lompoc California; from John Minnerath of Crowheart, Wyoming; from John Stetson of Falmouth, Maine; from Thomas Ashcraft of New Mexico;

  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 April 18, 2012 there were 1287 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2012 GY11
Apr 14
9 LD
--
21 m
2012 GW11
Apr 18
4.9 LD
--
23 m
1996 SK
Apr 18
67.2 LD
--
1.6 km
2007 HV4
Apr 19
4.8 LD
--
8 m
2012 GP1
Apr 21
9 LD
--
26 m
2012 HE
Apr 22
6.9 LD
--
33 m
2012 HQ
Apr 24
9.8 LD
--
41 m
2012 HM
Apr 28
1.4 LD
--
86 m
2011 WV134
Apr 28
38.6 LD
--
1.6 km
1992 JD
May 2
9.5 LD
--
43 m
2010 KK37
May 19
2.3 LD
--
31 m
4183 Cuno
May 20
47.4 LD
--
5.7 km
2002 VX94
May 26
72.8 LD
--
1.1 km
2002 AC
Jun 16
62.2 LD
--
1.2 km
1999 BJ8
Jun 16
68.8 LD
--
1.1 km
2005 GO21
Jun 21
17.1 LD
--
2.2 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
Trade Show Displays
   
  more links...
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