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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
SPACE WEATHER
Current conditions
Solar wind
speed: 475.4 km/sec
density: 3.8 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A2
2255 UT Apr15
24-hr: A3
0325 UT Apr15
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 15 Apr. 10
The Earth-facing side of the sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 12
What is the sunspot number?
Updated 14 Apr 2010

Spotless Days
Current Stretch: 0 days
2010 total: 7 days (7%)
2009 total: 260 days (71%)
Since 2004: 777 days
Typical Solar Min: 485 days
explanation | more info
Updated 14 Apr 2010


The Radio Sun
10.7 cm flux: 75 sfu
explanation | more data
Updated 14 Apr 2010

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 4
unsettled
explanation | more data
Interplanetary Mag. Field
Btotal: 2.6 nT
Bz: 1.1 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2010 Apr 15 2201 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
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: 2010 Apr 15 2201 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
25 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
30 %
MINOR
01 %
05 %
SEVERE
01 %
01 %
What's up in Space
April 15, 2010

NEW AND IMPROVED: Turn your iPhone or iPod Touch into a field-tested global satellite tracker. The Satellite Flybys app now works in all countries.

 

VOLCANIC SUNSET ALERT: A cloud of ash from the Iceland's Eyjafjallajokull volcano is drifting across Europe today. This has caused a massive disruption in air travel, as many countries have grounded their planes. On the bright side, the cloud is causing sunsets of rare beauty. Europeans should look west at the end of the day. Images: #1, #2, #3, #4.

BONUS: If you don't live in Europe, look west anyway. There's something for you to see, too. Venus, Mercury and the crescent Moon are beaming through the twilight. Sky maps: April 15, 16.

MIDWESTERN FIREBALL: Last night, around 10:05 pm CDT, sky watchers in Minnesota, Wisconsin, Iowa, Illinois and Missouri witnessed a brilliant green fireball streaking across the sky. Images from a rooftop webcam in Madison, Wisconsin, show a brilliant midair explosion:


Credit: University of Wisconsin - AOS/SSEC

The fireball was caused by a small asteroid hitting Earth's atmosphere at a shallow angle. Preliminary infrasound measurements place the energy of the blast at 20 tons of TNT (0.02 kton), with considerable uncertainty. Bill Cooke of NASA's Meteoroid Environment Office estimates that the space rock was about 1 meter wide and massed some 1260 kg. "Fireballs of this size are surprisingly common," he notes. "They hit Earth about 14 times a month, on average, although most go unnoticed because they appear during the day or over unpopulated areas."

Many readers have asked if fragments of the meteoroid might have reached Earth. The answer is yes. Cooke advises looking directly underneath the fireball's debris trail, which was pinged by National Weather Service radars in Iowa. Click here and here for maps.

AURORA WATCH: A solar wind gust hit Earth's magnetic field on April 15th, sparking a G1-class (Kp=5) geomagnetic storm. Skies over Finland lit up with a beautiful mix of green and purple:

"We had a good display for about an hour," says photographer 'JTbo' of Saarijarvi, Finland. "This spring has been something special as the auroras seem to be very strong."

They could become stronger in the nights ahead. A coronal mass ejection (movie) blasted into space by an erupting prominence on April 13th could deliver a glancing blow to Earth's magnetic field on or about April 17th. (Note: This supercedes earlier estimates of an April 15th arrival.) High-latitude sky watchers should remain alert for auroras.

April Northern Lights Gallery
[previous Aprils: 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 15, 2010 there were 1117 potentially hazardous asteroids.
April 2010 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2010 GV23
April 5
2.1 LD
19
12 m
2010 GF7
April 8
2.8 LD
18
30 m
2010 GA6
April 9
1.1 LD
16
27 m
2010 GM23
April 13
3.4 LD
17
47 m
2005 YU55
April 19
5.9 LD
15
185 m
2009 UY19
April 23
8.8 LD
18
87 m
2002 JR100
April 29
8.0 LD
19
65 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 Links
NOAA Space Weather Prediction Center
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Atmospheric Optics
  The first place to look for information about sundogs, pillars, rainbows and related phenomena.
Solar and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
STEREO
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Daily Sunspot Summaries
  from the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
Science Central
   
  more links...
   
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