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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 594.9 km/sec
density: 2.1 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Aug18
24-hr: A0
0425 UT Aug18
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 18 Aug 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 17 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= 3 quiet
24-hr max: Kp= 5
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 5.3 nT
Bz: 0.6 nT north
explanation | more data
Updated: Today at 2247 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about Aug. 18th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2008 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: 2008 Aug 18 2201 UTC
0-24 hr
24-48 hr
35 %
10 %
10 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
50 %
15 %
15 %
05 %
01 %
01 %
What's up in Space
August 18, 2008
AURORA ALERTS: Did you miss the Northern Lights of August 9th? Next time get a wake-up call from Space Weather PHONE.  

AURORA WATCH: High latitude sky watchers, be alert for auroras tonight. Earth is entering a solar wind stream, and the encounter could spark geomagnetic storms: gallery.

WEEKEND ECLIPSE: On Saturday, Aug. 16th, Earth's shadow fell across the Moon producing a partial lunar eclipse visible from every continent except North America. Italian photographer Marco Fulle calls this photo of the event Miss Eclipse:

"Local students put on a show demonstrating how eclipses work," he explains. "As part of the project, they had to calculate the geometry of a simulated eclipse. The shadow made by their classroom globe, for instance, had to be 38 times the size of the globe itself to match Earth's actual shadow. Then they had to find a local building with the right orientation and architecture for shadow casting. The New Church of San Giovanni near Trieste, Italy, was selected for this purpose."

"The final result was a projected shadow so perfectly matching the real Earth one, that the student holding the globe seemed to be the real actor responsible of the ongoing eclipse," marvels Fulle.

Congratulations, Miss Eclipse, on a job well done! More information about the performance may be found on page 4 of the eclipse gallery:

Aug. 16th Lunar Eclipse Gallery
[Interactive Eclipse Map]

PERSEID ECHOES: In a remote corner of New Mexico, amateur astronomer Thomas Ashcraft has found that he can tell when a meteor is shooting overhead with his eyes closed. You can do it, too. Position your mouse over the image below. Close your eyes, and click:

Click to listen

Did you hear it? About 16 seconds into movie, a Perseid fireball split the screen and produced an eerie warbling sound.

"That sound was a radio echo, caused by distant radio stations bouncing off the meteor's trail," explains Ashcraft, who operates a combo all-sky camera and radio meteor monitoring station at his home in New Mexico. He recorded the fireball during the peak of the Perseid meteor shower on August 13th.

When meteors cut through Earth's atmosphere, they heat the air enough to break apart atoms and molecules, producing an electrically-charged plasma that reflects radio waves. Ashcraft's receivers picked up echoes at 61 MHz (TV channel 3) and 83 MHz (TV channel 6). "For full effect, try listening with stereo headphones," he advises (61 MHz is in the left channel, 83 MHz in the right). "My complete collection of Perseid echoes can be found here."

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

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, 2008 , there were 971 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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