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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 383.0 km/sec
density: 5.7 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: B1
2015 UT May11
24-hr: B1
2015 UT May11
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 11 May 10
There are no sunspots on the Earth-facing side of the sun. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 10 May 2010

Spotless Days
Current Stretch: 2 days
2010 total: 23 days (18%)
2009 total: 260 days (71%)
Since 2004: 793 days
Typical Solar Min: 485 days
explanation | more info
Updated 10 May 2010

The Radio Sun
10.7 cm flux: 74 sfu
explanation | more data
Updated 10 May 2010

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 3
explanation | more data
Interplanetary Mag. Field
Btotal: 4.4 nT
Bz: 0.2 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2010 May 11 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 11 2201 UTC
0-24 hr
24-48 hr
30 %
25 %
10 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
35 %
30 %
15 %
10 %
01 %
01 %
What's up in Space
May 11, 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.


SPACE STATION FLYBYS: This week, the International Space Station (ISS) is making a series of bright evening flybys over North America. If you live in this part of the world, check the Simple Satellite Tracker for viewing times. And don't forget, there's an app for that, too.

ISS photos: from Jason Brotski of Dunbar, Wisconsin; from Mark Humpage of Walcote, UK; from Ralf Vandebergh of the Netherlands

PARTING SHOT: The "Mother's Day Flare Show" came to an end on May 9th when active sunspot 1069 rotated over the sun's western horizon. But wait--there's more to see. Even after the sunspot departed, it continued to hurl material up and over the limb. Click on the arrow to view a parting shot:

Movies: 1 MB mpg (web), 0.7 MB m4v (iPad), 0.2 MB m4v (iPhone)

NASA's Solar Dynamics Observatory recorded the eruption using the Atmospheric Imaging Assembly (AIA), a bank of telescopes that views the sun at multiple extreme ultraviolet wavelengths. The AIA's 171 Å filter (false-color blue) traces magnetized gas with temperatures around a million degrees K. This means the eruption you just witnessed was hot.

Can't get enough? Watch more SDO movies here and here.

IONOSPHERIC DISTURBANCE: On May 5th, a pair of solar flares bathed Earth's upper atmosphere in X-rays and caused a double-wave of ionization to sweep over the Americas. This improved the propagation of low-frequency radio signals, which use the ionosphere as a reflector to skip over the horizon. Rogerio Marcon of Campinas SP Brasil was monitoring a 24 kHz aviation beacon when the flares occurred, and he recorded a double-surge in the beacon's signal strength:

Each of the spikes is called a "SID," short for sudden ionospheric disturbance. One was produced by a C9-class flare at 11:52 UT; the other by a slightly stronger M1-class flare at 17:19 UT. The two SIDs ride atop a slower undulation in radio signals caused by the daily rising and setting of the sun. In terms of radio propagation, the two flares were as significant as the sunrise itself!

With solar activity on the rise, sudden ionospheric disturbances will become more common. Interested? Stanford University tells you how to build your own SID monitor.

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 11, 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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