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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 440.5 km/sec
density: 1.8 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Apr12
24-hr: A0
2340 UT Apr12
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 12 Apr 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 12 Apr 2009

NEW: Spotless Days
Current Stretch: 17 days
2009 total: 89 days (87%)
Since 2004: 600 days
Typical Solar Min: 485 days
explanation | more info
Updated 12 Apr 2009

Far side of the Sun:
This holographic image reveals no sunspots on the far side of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 3.5 nT
Bz: 2.1 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole could reach Earth on April 15th or 16th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Apr 12 2201 UTC
0-24 hr
24-48 hr
01 %
01 %
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: 2009 Apr 12 2201 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
What's up in Space
April 12, 2009

AURORA ALERT: Did you sleep through the Northern Lights? Next time get a wake-up call: Spaceweather PHONE.


RADIO STORM ON JUPITER: Jupiter has radio storms and yesterday Thomas Ashcraft of New Mexico heard one. The loudspeaker of his 21 MHz amateur radio telescope popped and crackled loudly as natural radio lasers in Jupiter's magnetosphere swept their beams past Earth in rapid-fire succession. Electrical currents flowing between Jupiter's upper atmosphere and the volcanic moon Io can boost these emissions to power levels easily detected by ham radio antennas on Earth. Click here and here to listen.

HAPPY EASTER: "Last night, I went outside and found a giant red Easter Egg," says Albert Engert of Uengershausen, Germany. "Upon closer inspection, however, I realized that it was just the Moon." He recorded his Easter moment using a Canon EOS 450D:

This Easter Egg doppleganger is indeed the Moon. Hanging near the horizon, it has been squashed by atmospheric refraction and reddened by the scattering effects of molecules in the air. Sometimes the Moon adopts other Easter colors: orange, green, pink, yellow, cobalt, and even red, white and blue.

"Happy Easter!" says Engert.

SUNDOGS AND DONKEY SHADOWS: The next time you're out walking on a sunny day and you meet a donkey, duck into its shadow. It's a great place to find rings around the sun:

On April 12th, Erwan Henry of Carnac, France, followed those instructions and counted no fewer than five different ice haloes: "I saw a parhelic circle with sundogs, a 22o sun halo, an upper tangent arc and an infralateral arc. I was so happy to see an entire parhelic circle for the first time!"

Halos like these are often overhead--and just as often overlooked because there's no one around to block the glare. Can't find a donkey? Fingers, trees, flags and weather globes work, too. Take a look!

Explore the Sunspot Cycle

April 2009 Aurora Gallery
[previous Aprils: 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 12, 2009 there were 1050 potentially hazardous asteroids.
April 2009 Earth-asteroid encounters:
Miss Distance
2009 FU30
Apr. 2
8.8 LD
44 m
2004 VC
Apr. 3
51.3 LD
785 m
2002 EB3
Apr. 10
41.3 LD
1.3 km
2003 SG170
Apr. 19
57.7 LD
1.2 km
2009 FJ30
Apr. 24
9.7 LD
130 m
2001 VG5
Apr. 26
58.5 LD
2.1 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 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 and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
  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...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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