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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 463.6 km/sec
density: 5.9 protons/cm3
explanation | more data
Updated: Today at 2244 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Aug13
24-hr: A0
0125 UT Aug13
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 13 Aug 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 13 Aug. 2008
Far side of the Sun:
This holographic image reveals no sunspots on the far side of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 1.3 nT
Bz: 0.5 nT north
explanation | more data
Updated: Today at 2246 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2008 Aug 13 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: 2008 Aug 13 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
August 13, 2008
AURORA ALERTS: Did you miss the Northern Lights of July 12th? Next time get a wake-up call from Space Weather PHONE.  

TIGER STRIPES: High-resolution images of tiger stripes on Enceladus have just arrived from Saturn. The photos, taken by NASA's Cassini probe, reveal a sharply grooved landscape littered with blocks of ice. Researchers are working now to match up features in the photos with geysers of icy water seen in earlier flybys. Stay tuned for updates and, meanwhile, take a look at the images.

DON'T STOP WATCHING: The Perseid meteor shower is still active. International observers counted 100 meteors per hour at maximum on August 13th: data. The shower is presumably declining now, not to zero. Some 20 to 40 meteors per hour may yet be seen during the dark hours before dawn on Thursday, Aug. 14th.

Earlier today, an exploding Perseid fireball left this smoky trail of debris over Pauleasca, Romania:

"I missed the fireball itself, but photographed the debris twisting in the wind," says photographer Vlad Dumitrescu. "Later, the trail made a loop and encircled the Pleiades. Here is the entire sequence."

2008 Perseid Meteor Gallery
[Previous Perseids: 2007, 2006, 2005, 2004, 2002, 2001 ]

MAMMATUS CLOUDS: It is a curious fact of Nature that the underbelly of an exhausted thunderstorm resembles the underbelly of a cow. These are called mammatus clouds:

Andy Jarosz took the picture just hours ago in rain-soaked St Albans, UK. It was once thought that this type of cloud signaled the approach of bad weather, but new research shows the opposite is true. Mammatus clouds are most often seen when storms are breaking up. Indeed, "these appeared at the end of a very stormy day," he says.

What exactly causes mammatus clouds? It's a big undulating mystery. For details, see "The Mysteries of Mammatus Clouds," D. M. Schultz et al, Journal of the Atmospheric Sciences, Volume 63, Issue 10 (October 2006).

August 2008 Aurora Gallery
[Aurora Alerts] [Previous Augusts: '07, 06, 05, 04, 03, 02]

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 13, 2008 , there were 972 potentially hazardous asteroids.
August 2008 Earth-asteroid encounters:
Miss Distance
54509 YORP
Aug. 1
67 LD
130 m
2008 PK9
Aug. 11
11 LD
50 m
2008 ON10
Aug. 11
12 LD
50 m
2001 RT17
Aug. 14
69 LD
1.2 km
1991 VH
Aug. 15
18 LD
1.8 km
2008 MZ
Aug. 31
60 LD
1.1 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 bureau for real-time monitoring of solar and geophysical events, research in solar-terrestrial physics, and forecasting solar and geophysical disturbances.
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.
Daily Sunspot Summaries
  From the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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