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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 354.2 km/sec
density: 2.0 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A4
1930 UT Apr25
24-hr: A7
0600 UT Apr25
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 25 Apr. 10
This magnetic map of the sun shows a broad region of positive (white) and negative (black) magnetic fields near disk center. These fields have not coalesced to form a dark-cored sunspot. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 24 Apr 2010

Spotless Days
Current Stretch: 10 days
2010 total: 17 days (15%)
2009 total: 260 days (71%)
Since 2004: 787 days
Typical Solar Min: 485 days
explanation | more info
Updated 24 Apr 2010

The Radio Sun
10.7 cm flux: 74 sfu
explanation | more data
Updated 24 Apr 2010

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 2.8 nT
Bz: 0.5 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
A new coronal hole may be forming on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2010 Apr 25 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 25 2201 UTC
0-24 hr
24-48 hr
15 %
35 %
05 %
15 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
40 %
10 %
15 %
01 %
01 %
What's up in Space
April 25, 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.


VENUS AND THE PLEIADES: Tonight, shortly after sunset, go outside and look west. There's Venus--you can't miss it. Can you also see the faint star cluster right beside Venus? Venus and the Pleiades are in conjunction this weekend, only a few degrees apart. Using binoculars, scan the sky around Venus and you'll easily see the Pleiades, too. [sky map]

"QUIET" SUN: The sun has been without spots for ten consecutive days, prompting some observers to label the sun "quiet." But just how quiet can a 1027 ton nuclear explosion actually be? "Let us remember that the sun is never truly 'inactive' or 'boring,'" says astrophotographer Wouter Verhesen. "Stunning, fiery beauty lies just 150,000,000 km away--every day!" He sends this snapshot of the inferno from his backyard observatory in Sittard, The Netherlands:

Verhesen focused his solar telescope on an active region near disk center. It's a place where solar magnetic fields are intense, but not quite intense enough to form a dark-cored sunspot. The sun's atmosphere in this area is a veritable tempest of hot, magnetized plasma, and a fine target for backyard solar telescopes.

Spotless? Yes. But maybe not so quiet, after all. More images: from Cai-Uso Wohler of Bispingen, Germany; from Martin Gembec of Jablonec nad Nisou, Czech Republic; from Pascal Paquereau of Pouillé, Vendée, France.

MIDNIGHT LIGHTS: A solar wind stream is buffeting Earth's magnetic field and causing auroras around the Arctic Circle. In Alaska, the green lights have been dancing across a canvas of twilight blue. "The sky no longer gets dark here at 65° north," reports LeRoy Zimmerman of Fairbanks. "The northern horizon now has constant light all night long. I took these panoramic shots during the midnight hours of April 22nd."

"The auroras were soft and quiet, but lovely to watch," he continues. "It's a little sad to have the auroras active again just as we are losing our darkness. I reckon I have only ten more days of photography left before the midnight sun completely spoils the show."

"On the bright side," he points out, "it was not cold! I was outdoors from about midnight until 2:00am local time and felt comfortable the whole time."

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 25, 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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