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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 320.5 km/sec
density: 0.7 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: M1
1745 UT Apr16
24-hr: M1
1745 UT Apr16
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 16 Apr 12
Sunspot 1459 is large, but its magnetic field is simple, posing little threat for strong flares. Credit: SDO/HMI
Sunspot number: 77
What is the sunspot number?
Updated 15 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 15 Apr 2012


The Radio Sun
10.7 cm flux: 102 sfu
explanation | more data
Updated 15 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= 2
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 3.1 nT
Bz: 1 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 16 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 16 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
20 %
20 %
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 16 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
15 %
15 %
SEVERE
10 %
10 %
 
Monday, Apr. 16, 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

LYRID METEOR SHOWER: Earth is approaching the debris field of ancient Comet Thatcher, source of the annual Lyrid meteor shower. Forecasters expect the shower to peak on April 21-22; a nearly-new moon on those dates will provide perfect dark-sky conditions for meteor watching. Usually the shower is mild (10-20 meteors per hour) but unmapped filaments of dust in the comet's tail sometimes trigger outbursts 10 times stronger. [video] [Lyrid chat]

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 recorded the blast at extreme ultraviolet wavelengths:

The explosion, which registered M1.7 on the Richter Scale of solar flares, was not Earth-directed. A CME produced by the blast is likely to hit NASA's STEREO-B spacecraft, but probably no planets.

This event confirms suspicions that an active region of significance is rotating onto the Earth-facing side of the sun. Stay tuned for updates. Solar flare alerts: text, phone.

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

SATURN'S RINGS AT THEIR BEST: This week Saturn is at opposition--directly opposite the sun in the skies of Earth. The ringed planet rises at sunset and soars high in the sky at midnight, up all night long. Opposition is the time when Saturn's rings are at their best. From the point of view of Earth, shadows in the ring plane almost completely disappear (just as your own shadow tries to hide beneath your feet at noon) and sunlight is directly backscattered by icy ring particles toward our planet.

Amateur astronomer Christopher Go photographed the brightening rings on April 12th:

"Saturn is close to opposition and the rings are brightening. This is the Seeliger Effect," says Go. "Also a Northern Electrostatic Disturbance, which was detected by Cassini a few days ago, can be seen as a white patch north of the green belt."

Saturn is easy to find. Look south at midnight. The ringed planet forms a "double star" with Spica. [sky map]

more images: from Efrain Morales Rivera of Aguadilla, Puerto Rico

  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 16, 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
--
25 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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