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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 374.4 km/sec
density: 1.8 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A4
2335 UT Apr28
24-hr: A4
2335 UT Apr28
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 28 Apr. 10
The Earth-facing side of the sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 27 Apr 2010

Spotless Days
Current Stretch: 13 days
2010 total: 20 days (17%)
2009 total: 260 days (71%)
Since 2004: 790 days
Typical Solar Min: 485 days
explanation | more info
Updated 27 Apr 2010

The Radio Sun
10.7 cm flux: 75 sfu
explanation | more data
Updated 27 Apr 2010

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 3.3 nT
Bz: 1.3 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole could reach Earth on or about May 3rd. Credit: STEREO-B Extreme UV Telescope
NOAA Forecasts
Updated at: 2010 Apr 28 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: 2010 Apr 28 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 28, 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.


SPROUTING GRASS MOON: According to folklore, tonight's full moon has a special name, the Sprouting Grass Moon, because it shines down on the new grasses of northern spring. Fun: Go outside after dark and look at the ground. Does the grass look green or blue? The answer may surprise you.

PLASMA RAIN: NASA's Solar Dynamics Observatory (SDO) has just observed a massive eruption on the sun. Movies ten times better than HDTV show billions of tons of material blasting into space while debris from the explosion rains around the blast site. Moon-sized fragments of plasma splash brightly when they land back on the sun's surface:

Above: "Plasma rain" photographed by SDO on April 19, 2010

Veteran solar physicists say they've never seen anything quite like it. The fluid detail of SDO's imagery is unprecedented, prompting NASA to dub it their "Hubble for the Sun."

SDO has already solved one mystery of plasma rain: The rain falls with puzzling slowness, seemingly resisting the sun's powerful gravity. What slows the descent? The phenomenon is explained in today's story from Science@NASA.

PLANET WEIKERSHEIM: For several days last week, something unusual happened in the skies of Europe: air traffic came to a halt. Almost every flight was grounded because of the volcano in Iceland. "The sky took on a strange appearance," reports Jens Hackmann of Weikersheim, Germany. "It was totally uninterrupted by contrails! So, I took several pictures using my Canon 5D Mark II and put them together in the form of a 'little planet' panorama."

The dome in the image is Hackman's backyard observatory. Planet Weikersheim appears to be hollow, but that's just because "I forgot to take pictures of the ground," explains Hackmann. "But who wants to see my feet?" Indeed.

Star trails also looked great during the flight ban. Click here for vertigo.

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 28, 2010 there were 1116 potentially hazardous asteroids.
April 2010 Earth-asteroid encounters:
Miss Distance
2010 GV23
April 5
2.1 LD
12 m
2010 GF7
April 8
2.8 LD
30 m
2010 GA6
April 9
1.1 LD
27 m
2010 GM23
April 13
3.4 LD
47 m
2005 YU55
April 19
5.9 LD
185 m
2009 UY19
April 23
8.8 LD
87 m
2002 JR100
April 29
8.0 LD
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
  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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