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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: 3.7 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: B3
2225 UT Aug18
24-hr: C4
0545 UT Aug18
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 18 Aug 10
Sunspots 1098 and 1100 are small and relatively quiet.
Resolutions: 4096, 1024, 512
Sunspot number: 26
What is the sunspot number?
Updated 17 Aug 2010

Spotless Days
Current Stretch: 0 days
2010 total: 35 days (15%)
2009 total: 260 days (71%)
Since 2004: 803 days
Typical Solar Min: 486 days
explanation | more info
Updated 17 Aug 2010

The Radio Sun
10.7 cm flux: 81 sfu
explanation | more data
Updated 17 Aug2010

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: 1 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole could reach Earth on or about Aug. 24th. Credit: SDO/AIA
NOAA Forecasts
Updated at: 2010 Aug 18 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 Aug 18 2201 UTC
0-24 hr
24-48 hr
10 %
10 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
10 %
10 %
01 %
01 %
01 %
01 %
What's up in Space
August 18, 2010

iPHONE VS ANDROID! Actually, it doesn't matter which phone you carry. Our cool, new app turns both smartphones into field-tested satellite trackers. Learn more.


WEAK IMPACT: There was no green snow in Antarctica last night. The CME expected to hit Earth's magnetic field on Aug. 17th either missed or delivered such a feeble blow that no one noticed the resulting geomagnetic disturbance. The next opportunity for auroras is Aug. 24th when an incoming solar wind stream could provoke polar geomagnetic storms. Stay tuned.

FARSIDE ERUPTION: This morning around 0500 UT, something exploded on the far side of the sun. NASA's STEREO-A spacecraft had a direct view of the blast, which produced a C4-class solar flare and hurled a bright coronal mass ejection (CME) over the sun's western limb:

Click to view a 0.7 MB movie of the CME

Based on STEREO-A imagery, the source of the eruption appears to be farside sunspot complex 1093-1099. Magnetic fields connecting the two sunspot groups became unstable and--bang! The blast was not directed toward Earth, so no geomagnetic storms are in the offing.

more images: from NASA's Solar Dynamics Observatory (SDO) in Earth orbit

RED SPOTS IN CONJUNCTION: What happens when a raging cyclone as wide as Earth bumps into another storm twice as large? The answer lies in the midnight sky. Two storms on Jupiter--the Great Red Spot and Oval BA--are having just such a close encounter. Amateur astronomer Anthony Wesley sends this picture from Exmouth, Australia:

The bigger storm is the Great Red Spot, which has been swirling around Jupiter for centuries. The smaller is upstart Oval BA, which formed less than ten years ago. Because the storms travel around Jupiter at different rates, they pass one another periodically, approximately every two years. And when they do ... not much happens. Previous encounters have shown, surprisingly, that the two colossal storms can converge and emerge in tact. Could this time be different?

"Oval BA and the Great Red Spot will be passing one another in the days ahead," says Wesley. "I plan to monitor developments."

more images: from Brian Combs of Buena Vista, GA; from Efrain Morales Rivera of Aguadilla, Puerto Rico; from Ralf Vandebergh of the Netherlands

2010 Perseid Photo Gallery
[meteor radar] [Perseid fireball cam]

August 2010 Northern Lights Gallery
[previous Augusts: 2009, 2008, 2007, 2006, 2005, 2004, 2003]

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 August 18, 2010 there were 1144 potentially hazardous asteroids.
Upcoming Earth-asteroid encounters:
Miss Distance
2002 CY46
Sep 2
63.8 LD
2.4 km
2010 LY63
Sep 7
56 LD
1.2 km
2009 SH2
Sep 30
7.1 LD
45 m
1998 UO1
Oct 1
32.1 LD
2.1 km
2005 GE59
Oct 1
77 LD
1.1 km
2001 WN5
Oct 10
41.8 LD
1.0 km
1999 VO6
Oct 14
34.3 LD
1.8 km
1998 TU3
Oct 17
69.1 LD
5.3 km
1998 MQ
Oct 23
77.7 LD
1.9 km
2007 RU17
Oct 29
40.6 LD
1.0 km
2003 UV11
Oct 30
5 LD
595 m
3838 Epona
Nov 7
76.8 LD
3.4 km
2005 QY151
Nov 16
77.7 LD
1.3 km
2008 KT
Nov 23
5.6 LD
10 m
2002 EZ16
Nov 30
73.9 LD
1.0 km
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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