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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 485.4 km/sec
density: 0.2 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: C1
1807 UT Apr06
24-hr: C1
1807 UT Apr06
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 06 Apr 11
None of these spots poses a threat for strong flares. Credit: SDO/HMI
Sunspot number: 65
What is the sunspot number?
Updated 05 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 05 Apr 2011

The Radio Sun
10.7 cm flux: 109 sfu
explanation | more data
Updated 05 Apr 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 6
explanation | more data
Interplanetary Mag. Field
Btotal: 4.7 nT
Bz: 0.6 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 06 Apr 11
A solar wind stream flowing from the indicated coronal hole could brush against Earth's magnetic field on April 10th or 11th. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Apr 06 2225 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: 2011 Apr 06 2225 UTC
0-24 hr
24-48 hr
25 %
15 %
10 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
30 %
20 %
15 %
05 %
01 %
01 %
Wednesday, Apr. 6, 2011
What's up in space

Metallic photos of the sun by renowned photographer Greg Piepol bring together the best of art and science. Buy one or a whole set. They make a stellar gift.

Metallic pictures of the Sun

DOUBLE ASTEROID FLYBY: It's notable when an asteroid flies past Earth closer than the Moon. Today, April 6th, two asteroids will do this. Newly-discovered space rocks 2011 GW9 and 2011 GP28 will zip through the Earth-Moon system at Earth-distances of 77,000 km and 192,000 km, respectively. Both are ten-meter class asteroids two to three times smaller than the Tunguska impactor of 1908. There is no danger of a collision.

ARCTIC AURORAS: The onset of spring has brought a growing twilight to the night skies of the Arctic. The sky may be bright, but the auroras are even brighter. Here is the view from northern Norway after "nightfall" on April 5th:

Photographer Øystein Ingvaldsen of Bø in Vesterålen was taking a late walk at the time of the display. "I did not expect to see Northern Lights," he says "but suddenly they appeared. This is the first time I have photographed auroras and a sunset all at once."

More Arctic lights are in the offing. A solar wind stream is buffeting Earth's magnetic field, and NOAA forecasters estimate a 15% - 25% chance of high-latitude geomagnetic activity during the next 24 hours. Aurora alerts are available here.

more images: from Frank Olsen on Hillesøy island outside Tromsø, Norway; from Valentin Clement and Guillaume Gravey of the Lofoten Islands, Norway; from Hanneke Luijting of Tromsø, Norway; from Chad Blakley of Abisko National Park, Sweden

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

UNSTABLE FILAMENT: An active filament of solar magnetism is snaking around the sun's southeastern limb today. Measuring more than 200,000 km along its sinuous backbone, the vast structure is in a constant state of motion. NASA's Solar Dynamics Observatory froze it in this snapshot taken 20:16 UT on April 5th:

Filaments as agitated as this one is often erupt and hurl parts of themselves into space. Because of the filament's location on the sun's limb, any such blast would not be Earth-directed, but it would be photogenic! Readers with solar telescopes are encouraged to monitor the action.

more images: from Z. Parsons-West and J. Stetson of South Portland, Maine; from Nicolas SOLDATI of Fribourg, Switzerland; from Peter Desypris of Athens,Greece

  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 6, 2011 there were 1214 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 GM44
Apr 1
9.2 LD
500 m
2011 GW9
Apr 6
0.5 LD
10 m
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
25 m
2011 FT53
Apr 9
6 LD
34 m
2011 GE
Apr 13
4.8 LD
26 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
1.1 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.
  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
  the underlying science of space weather
Conquest Graphics
  for out-of-this-world printing and graphics
Science Central
  more links...
©2010 All rights reserved. This site is penned daily by Dr. Tony Phillips.
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