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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 351.0 km/sec
density: 6.7 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: A3
1850 UT May10
24-hr: B1
1105 UT May10
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 10 May 10
Active sunspot 1069 has rotated over the sun's western limb, leaving the Earth-facing side of the sun spotless. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 09 May 2010

Spotless Days
Current Stretch: 1 days
2010 total: 22 days (17%)
2009 total: 260 days (71%)
Since 2004: 792 days
Typical Solar Min: 485 days
explanation | more info
Updated 09 May 2010

The Radio Sun
10.7 cm flux: 79 sfu
explanation | more data
Updated 09 May 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: 2.1 nT
Bz: -0.0 nT
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 10 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 10 2201 UTC
0-24 hr
24-48 hr
25 %
30 %
05 %
10 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
30 %
35 %
10 %
15 %
01 %
01 %
What's up in Space
May 10, 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 OUTLOOK: High latitude sky watchers should be alert for auroras on May 11th. That's when a disturbance in the solar wind (a "co-rotating interaction region") is expected to move past our planet and possibly disturb polar magnetic fields. NOAA forecasters estimate a 30% chance of geomagnetic activity.

AMAZING ERUPTIONS: This weekend, magnetic fields around sunspot 1069 became unstable and erupted--over and over again. On May 8th alone, the active region produced more than half a dozen flares. NASA's Solar Dynamics Observatory (SDO) video-recorded each of the explosions with a clarity ten times better than HDTV. Click on the image to view a sample "first look" movie:

Movies: 1.8 MB mpg (web), 0.7 MB m4v (iPad), 0.3 MB m4v (iPhone)

On the Richter scale of solar flares, the eruption you just witnessed registered C2.4. In years past, solar physicists regarded C-flares as minor events, but SDO is revealing them to be quite spectacular. Plasma plumes accelerating out of the blast site are filled with magnetized gas hotter than 80,000 K and are big enough to swallow Earth itself. Earth was not, however, in the line of fire, so we will feel no geomagnetic effects from these events.

Here are three more highlights from May 8th: C1.8-flare, C9-flare, B7-flare. These were selected from the Lockheed Martin Solar and Astrophysics Laboratory's excellent latest events web site.

Instigating sunspot 1069 has rotated over the sun's western horizon, out of sight of Earth and SDO, so the show is over for now. It probably won't be long, however, before SDO turns another "minor" eruption into a jaw-dropping spectacle. Stay tuned.

BONUS: SDO also observed a pair of impressive eruptions on May 5th: This one sent a "solar tsunami" rippling through the sun's atmosphere and this one propelled a massive magnetic filament off the sun's southwestern limb.

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 10, 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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