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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 472.8 km/sec
density: 1.8 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: C1
1911 UT Apr13
24-hr: C2
1343 UT Apr13
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 13 Apr 11
New sunspot 1190 is growing rapidly and could soon pose a threat for Earth-directed flares. Credit: SDO/HMI
Sunspot number: 114
What is the sunspot number?
Updated 12 Apr 2011

Spotless Days
Current Stretch: 0 days
2011 total: 1 day (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 820 days
Typical Solar Min: 486 days

Updated 12 Apr 2011


The Radio Sun
10.7 cm flux: 110 sfu
explanation | more data
Updated 12 Apr 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 4
unsettled
explanation | more data
Interplanetary Mag. Field
Btotal: 5.4 nT
Bz: 2.6 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 12 Apr 11
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Apr 13 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: 2011 Apr 13 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
 
Wednesday, Apr. 13, 2011
What's up in space
 

Are we alone? Your iPhone has the answer. Download the all-new Drake Equation app to calculate the population of the Milky Way.

 
DrakeEQ for iPhone and iPad

EMERGING SUNSPOTS: More solar activity could be in the offing. As sunspot 1190 grows rapidly near the center of the solar disk, a new and large sunspot is rotating over the sun's eastern limb. A 24-hour movie from the Solar Dynamics Observatory shows how the sunspot number is increasing. Stay tuned.

APRIL AURORAS: The auroras this month have been something to shout about. Just ask this happy sky watcher, photographed by Ruslan Akhmetsafin in Siberia on April 13th:

The display came at the tail end of a geomagnetic storm sparked by solar wind hitting Earth's magnetic field on April 12th. The event was so strong, it sent Northern Lights spilling over the Canadian border into US states such as Michigan and Minnesota. The storm has since subsided, but another flare up is possible as the solar wind continues to blow. Aurora alerts: voice, text.

April 2011 Aurora Gallery
[previous Aprils: 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002]

SUN HALOES: As a member of the member of the Astronomy Section of the Rochester Academy of Science, Brian Oyer has developed a habit: "I'm always looking up at the sky," he says, "even during the day." On Tuesday morning, April 12th, he was really glad he did:

"When I stepped out of my house in Greece, New York, I saw a network of luminous rings and arcs surrounding the sun. It was such a large display, I had to combine two exposures to capture the whole thing."

These are ice haloes, caused by sunlight shining through ice crystals in high cirrus clouds. An expert analyzing Oyer's snapshot would count at least six distinct halo-types: the 22o halo, a pair of sundogs, an upper tangent arc, a suncave Parry arc, a supralateral arc, and a circumzenithal arc. Click here for labels.

Looking up: It's not a bad habit, after all.

more images: from Alex McCombie of Mexico, NY


April 2011 Aurora Gallery
[previous Aprils: 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002]

  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 13, 2011 there were 1214 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 GP28
Apr 6
0.2 LD
--
6 m
2011 FT29
Apr 7
6.3 LD
--
38 m
2011 GZ2
Apr 8
2.7 LD
--
26 m
2011 FT53
Apr 9
6 LD
--
34 m
2011 GE
Apr 13
4.8 LD
--
28 m
2011 GP59
Apr 15
1.4 LD
--
60 m
2002 DB4
Apr 15
62.5 LD
--
2.2 km
2011 GJ3
Apr 27
7.7 LD
--
24 m
2008 UC202
Apr 27
8.9 LD
--
10 m
2009 UK20
May 2
8.6 LD
--
23 m
2008 FU6
May 5
75.5 LD
--
1.2 km
2003 YT1
May 5
65.3 LD
--
2.5 km
2002 JC
Jun 1
57.5 LD
--
1.6 km
2009 BD
Jun 2
0.9 LD
--
9 m
2002 JB9
Jun 11
71.5 LD
--
3.2 km
2001 VH75
Jun 12
42.2 LD
--
1.1 km
2004 LO2
Jun 15
9.9 LD
--
48 m
2001 QP181
Jul 2
35.1 LD
--
1.0 km
2011 GA55
Jul 6
63.7 LD
--
1.0 km
2003 YS117
Jul 14
73.9 LD
--
1.0 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
Conquest Graphics
  for out-of-this-world printing and graphics
Science Central
   
  more links...
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