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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
SPACE WEATHER
Current conditions
Solar wind
speed: 399.1 km/sec
density: 4.1 protons/cm3
explanation | more data
Updated: Today at 2245 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Aug21
24-hr: A0
2245 UT Aug21
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 21 Aug 08
For the first time in a month, a new sunspot is emerging. The relatively small spot poses no threat for solar flares. Credit: SOHO/MDI
Sunspot number: 11
What is the sunspot number?
Updated 21 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= 3
quiet
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 2.5 nT
Bz: 0.9 nT south
explanation | more data
Updated: Today at 2246 UT
Coronal Holes:
Earth is exiting a solar wind stream flowing from the indicated coronal hole. Credit: Hinode X-Ray Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2008 Aug 21 2201 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
CLASS X
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 21 2201 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
What's up in Space
August 21, 2008
AURORA ALERTS: Did you miss the Northern Lights of August 9th? Next time get a wake-up call from Space Weather PHONE.  

LIVING WITH A STAR: What if you woke up one morning and found your whole planet had been swallowed by the atmosphere of a star? Don't laugh, it could happen to you, and NASA has a special program to deal with it: full story.

NEW SUNSPOTS: A new sunspot is emerging near the sun's eastern limb. Pavol Rapavy sends this picture, taken just hours ago, from his backyard observatory in Rimavska Sobota, Slovakia:

These spots aren't large, but they are noteworthy as the first sunspots in more than a month. Moreover, they are growing rapidly, offering an opportunity for onlookers to witness sunspot genesis in action. If you have a solar telescope, take a look.

more images: from Pete Lawrence of Selsey, West Sussex, UK

OZONE FRINGE: When you think of a lunar eclipse, the color that comes to mind is red. The core of Earth's shadow is reddened by atmospheric scattering, and when that shadow falls across the Moon, the lunar landscape turns as red as a sunset. Yet telescopic observers of the Aug. 16th lunar eclipse saw another hue--turquoise:

This photo, taken by Theodoros Jiaourtsis of Nea Moudania, Greece, using an 8-inch telescope and a Canon 350D digital camera, shows how the inner red shadow has a pale blue-green circumference.

The source of the turquoise is ozone. Eclipse researcher Dr. Richard Keen of the University of Colorado explains: "Most of the light illuminating the moon passes through the stratosphere, and is reddened by scattering. However, light passing through the upper stratosphere penetrates the ozone layer, which absorbs red light and actually makes the passing light ray bluer!" This can be seen, he says, as a turquoise fringe around the red.

Browse the gallery for more ozone:

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

       
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 21, 2008 , there were 971 potentially hazardous asteroids.
August 2008 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
54509 YORP
Aug. 1
67 LD
22
130 m
2008 PK9
Aug. 11
11 LD
18
50 m
2008 ON10
Aug. 11
12 LD
19
50 m
2001 RT17
Aug. 14
69 LD
17
1.2 km
1991 VH
Aug. 15
18 LD
15
1.8 km
2008 MZ
Aug. 31
60 LD
17
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, SpaceWeather.com -- This site is penned daily by Dr. Tony Phillips.
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