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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 489.5 km/sec
density: 0.5 protons/cm3
explanation | more data
Updated: Today at 2342 UT
X-ray Solar Flares
6-hr max: A9
2005 UT Apr04
24-hr: B1
0900 UT Apr04
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 04 Apr. 10
These sunspots pose no threat for strong solar flares. Credit: SOHO/MDI
Sunspot number: 27
What is the sunspot number?
Updated 03 Apr 2010

Spotless Days
Current Stretch: 0 days
2010 total: 6 days (6%)
2009 total: 260 days (71%)
Since 2004: 776 days
Typical Solar Min: 485 days
explanation | more info
Updated 03 Apr 2010

The Radio Sun
10.7 cm flux: 77 sfu
explanation | more data
Updated 03 Apr 2010

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 4
explanation | more data
Interplanetary Mag. Field
Btotal: 5.2 nT
Bz: 0.1 nT north
explanation | more data
Updated: Today at 2345 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on April 6th or 7th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2010 Apr 04 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 04 2201 UTC
0-24 hr
24-48 hr
05 %
25 %
01 %
10 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
10 %
30 %
05 %
15 %
01 %
01 %
What's up in Space
April 4, 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.


SHUTTLE SKY SHOW: Thousands of people who gather in Florida on Monday morning, April 5th, to witness the dawn launch of space shuttle Discovery may get more than they bargained for. Fifteen minutes before the shuttle takes off, the International Space Station will soar over Cape Canaveral, past the gibbous Moon and almost directly above Discovery. How cool is that? Photographers in Florida should be prepared for the ISS flyby at 6:06 am EDT followed by the shuttle launch at 6:21 am EDT. Submit your images here.

SUNSET PLANETS: When the sun sets tonight, go outside and look west. Venus and Mercury are in conjunction, beaming through the twilight only 3o apart. Images #1, #2, #3, #4, #5.

MIDNIGHT SUN vs. AURORAS: For observers around the Arctic Circle, April marks the end of aurora season. The midnight sun is coming, and soon it will overwhelm the Northern Lights. "Soon, but not yet," says Ian Robins of Norway. "Last night at midnight, the last rays of sunlight were fading away when we witnessed a really strong burst of auroras. The whole sky lit up in a fantastic display over Hovden in the Vesterålen islands."

"It was something special to see the auroras with the last light of the day still lingering in the background," says Robins. "I recorded the scene using a Nikon 300D set at ISO 800 for 30 seconds."

High-latitude photographers, take note of those settings. The solar wind continues to blow, so there could be another photo-op tonight.

UPDATED: April Northern Lights Gallery
[previous Aprils: 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002]

IN THE EYE OF THE BEHOLDER: Do dogs appreciate the sky? Tony Phillips, author of and a longtime dogsledder with twenty Siberian huskies in his backyard, believes the answer could be "yes." Many times he's heard the songs huskies sing at the Moon and caught pairs of blue eyes fixed on a starry sky. It always seems to be more than just a blank stare.

With these points in mind, consider the folowing:

Károly Vicián took the picture on April 4th in Heréd, Hungary. "We had a lot of high cirrus around noontime," he says. "When sunlight hit those icy clouds, a vivid 22o halo appeared in the sky. Later I sighted it in my dog's eye when we were playing, and I bent over for a quick shot with my Nikon D80."

Is it just a reflection, or is there beauty in the eye of the beholder? Readers must decide for themselves; Vicián's dog refuses to say.

more images: from Roberta Welton of Monarch, Utah; from Tibor Hollósy of Budapest, Hungary; from Gilles Boutin of Parc des Pingualuit Nunavik

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 4, 2010 there were 1110 potentially hazardous asteroids.
March 2010 Earth-asteroid encounters:
Miss Distance
2001 PT9
March 3
11.1 LD
305 m
4486 Mithra
March 12
73.5 LD
3.3 km
2001 FM129
March 13
44.1 LD
1.5 km
2010 FU9
March 18
1.5 LD
19 m
2010 EF43
March 18
5.0 LD
23 m
2010 FT
March 27
5.5 LD
33 m
2002 TE66
March 28
48.0 LD
940 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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