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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 618.0 km/sec
density: 0.2 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: A6
2045 UT May31
24-hr: A6
2045 UT May31
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 31 May 10
All three sunspots on the Earth-facing side of the sun are rapidly fading away. Credit: SOHO/MDI
Sunspot number: 40
What is the sunspot number?
Updated 30 May 2010

Spotless Days
Current Stretch: 0 days
2010 total: 33 days (22%)
2009 total: 260 days (71%)
Since 2004: 801 days
Typical Solar Min: 486 days
explanation | more info
Updated 30 May 2010

The Radio Sun
10.7 cm flux: 73 sfu
explanation | more data
Updated 30 May 2010

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 4
explanation | more data
Interplanetary Mag. Field
Btotal: 5.5 nT
Bz: 4.9 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SDO/AIA
NOAA Forecasts
Updated at: 2010 May 31 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 May 31 2201 UTC
0-24 hr
24-48 hr
20 %
15 %
05 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
25 %
25 %
10 %
05 %
01 %
01 %
What's up in Space
May 31, 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.


AURORA WATCH: A solar wind stream is buffeting Earth's magnetic field, and NOAA forecasters estimate a 40% chance of geomagnetic activity during the next 24 hours. High latitude sky watchers should be alert for auroras.

HI-RES MAGNETIC FILAMENT: A long, dark magnetic filament is looping over the sun's northeastern limb today. Click on the image to see the structure in magnificent 4096x4096 resolution:

NASA's Solar Dynamics Observatory took the picture just a few hours ago using the highest-resolution cameras ever flown on a mission to study the sun. Plasma trapped inside the filament is dense and cool relative to the seething inferno below. If the filament collapses, as filaments often do, the plasma could hit the surface and explode, producing a Hyder flare or a coronal mass ejection (CME). Readers with solar telescopes are encouraged to monitor developments.

more images: from Robert Arnold of Isle of Skye, Scotland; from Steve Riegel of Santa Maria, CA; from Cai-Uso Wohler of Bispingen, Germany; from Rogerio Marcon of Campinas SP Brasil; from Alan Friedman of Buffalo, NY; from Matthias Juergens of Gnevsdorf, Germany;

JUPITER-ISS CONJUNCTION: On Saturday, May 29th, the International Space Station (ISS) had a conjunction with Jupiter ... in broad daylight. Amateur astronomer Anthony Ayiomamitis of Athens, Greece, recorded the flyby:

The trick, says Ayiomamitis, was focusing. "Focusing the telescope was very difficult against the mostly-blank blue sky. And there were no big sunspots I could use to fine-tune the focus by observing the sun. I got very lucky!"

His photo shows that with ISS construction now mostly complete the space station subtends an angle bigger than the biggest planet. "Jupiter has an apparent diameter of 37.5 arcseconds, which is second to the passing ISS at 42.1 arcseconds," he notes.

Last week he also photographed the space station transiting the sun. "Broad daylight is an interesting time for ISS photography," he says. Blue-sky transit forecasts may be found at

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 May 31, 2010 there were 1127 potentially hazardous asteroids.
May 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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