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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 501.7 km/sec
density: 0.8 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A5
2020 UT Jul04
24-hr: A5
1050 UT Jul04
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 04 Jul 10
Sunspot 1084 is big but very quiet. No solar flares are in the offing. Credit: SOHO/MDI
Sunspot number: 11
What is the sunspot number?
Updated 02 July 2010

Spotless Days
Current Stretch: 0 days
2010 total: 35 days (19%)
2009 total: 260 days (71%)
Since 2004: 803 days
Typical Solar Min: 486 days
explanation | more info
Updated 02 July 2010

The Radio Sun
10.7 cm flux: 73 sfu
explanation | more data
Updated 01 July 2010

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 3.4 nT
Bz: 1.4 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
Earth is exiting a solar wind stream flowing from the indicated coronal hole. Credit: SDO/AIA
NOAA Forecasts
Updated at: 2010 Jul 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 Jul 04 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
July 4, 2010

ANDROID FLYBYS: Our field-tested satellite tracker is now available for Android phones. Features: Global predictions and flyby alarms! Learn more.


PROGRESS 38 DOCKED: Two time's a charm. Russia's Progress 38 supply ship docked to the ISS at 12:17 pm EDT on Sunday, July 4th. The Progress 38 had earlier failed to latch onto the ISS when TV signals from a transmitter in the space station's Zvezda module interfered with the automated docking system. Get the full story from NASA.

4TH OF JULY FIREWORKS: It has been a busy weekend on the sun. So far the Solar and Heliospheric Observatory (SOHO) has recorded no fewer than five CMEs blasting out of the sun's atmosphere. Click on the image to set the clouds in motion:

Movies: 3 MB gif, 1.5 MB gif, 1.0 MB iPad, 0.6 MB iPhone

The two brightest CMEs, pictured above, were caused by eruptions of unrelated magnetic filaments on opposite sides of the sun. The origin of the other three CMEs in the movie remains uncertain. None of the clouds appears to be heading toward Earth; the display was photogenic, but not geoeffective.

Stay tuned for follow-up movies from the Solar Dynamics Observatory, which should reveal some of the blast sites in greater detail.

NOCTILUCENT DAWN: This morning's sunrise over the UK was highlighted by an unusual color: electric blue. "We had a bright display of noctilucent clouds on July 4th," reports Pete Lawrence, who sends this snapshot from the south coast of England.

"This is the first really vivid electric blue display for me this year," says Lawrence. "I'm keeping my fingers crossed for more in the coming days."

He's likely to get his wish. Summer is the season for NLCs, and the recent solstice has kicked off a period of high activity. Indeed, the mysterious clouds were so bright over Northern Ireland on July 3rd, they could be seen reflecting from the River Bann. In Sweden, photographer P-M Hedén made a time-lapse movie of the clouds "rumbling in" over a busy horse pasture outside Vallentuna. "They were all over the sky--even in the south!" he says. High-latitude sky watchers should remain alert for electric blue.

Observing tips: Look west 30 to 60 minutes after sunset or before sunrise when the sun is 6o to 16o below the horizon. If you see luminous blue-white tendrils spreading across the sky, you may have spotted a noctilucent cloud.

more images: from Hazel Mulheron of Widley, Hampshire; from Grant Privett of Fovant, Wiltshire, UK; from Martin Stirland of Winterton On Sea, Norfolk, England; from Ken Osborne of Nr Ilminster, Somerset;

Lunar Eclipse Photo Gallery
[Science@NASA: Big Lunar Eclipse] [astronomy alerts]

May 2010 Aurora Gallery
[previous Mays: 2008, 2005, 2004, 2003, 2002] [aurora alerts]

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 July 4, 2010 there were 1138 potentially hazardous asteroids.
June-July 2010 Earth-asteroid encounters:
Miss Distance
2010 JR34
May 14
5.8 LD
12 m
2003 HR32
May 17
55.2 LD
1.0 km
2010 JN71
May 26
8.2 LD
245 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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