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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: 422.6 km/sec
density: 2.2 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Aug23
24-hr: A0
0335 UT Aug23
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 23 Aug 09
The sun is blank--no sunspots. Photo credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 22 Aug 2009

Spotless Days
Current Stretch: 43 days
2009 total: 185 days (79%)
Since 2004: 696 days
Typical Solar Min: 485 days
explanation | more info
Updated 22 Aug 2009

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= 0 quiet
24-hr max: Kp= 3
quiet
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Interplanetary Mag. Field
Btotal: 2.3 nT
Bz: 0.5 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
There are no coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2009 Aug 23 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: 2009 Aug 23 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 23, 2009

AURORA ALERT: Did you miss the Northern Lights? In July they descended as far south as Nebraska. Next time get a wake-up call: Spaceweather PHONE.

 

QUIET SUN: Today marks the 44th consecutive day without spots on the sun--one of the longest quiet spells of the current solar minimum. In early July, sunspot 1024 seemed to herald the long-awaited onset of Solar Cycle 24, but shortly after that apparition, sunspot production turned off again. Deep solar minimum continues...

ARE SUNSPOTS DISAPPEARING? Sunspots are made of magnetism. The "firmament" of a sunspot is not matter but rather a strong magnetic field that appears dark because it blocks the upflow of heat from the sun's fiery depths. Without magnetism, there would be no sunspots.

That's what makes the following graph a little troubling:

According to Bill Livingston and Matt Penn of the National Solar Observatory in Tucson, Arizona, sunspot magnetic fields are waning. The two respected solar astronomers have been measuring solar magnetism since 1992. Their technique is based on Zeeman splitting of infrared spectral lines emitted by iron atoms in the vicinity of sunspots. Extrapolating their data into the future suggests that sunspots could completely disappear within decades. That would be a bummer for Spaceweather.com.

Don't count out sunspots just yet, however. While the data of Livingston and Penn are widely thought to be correct, far-reaching extrapolations may be premature. This type of measurement is relatively new, and the data reaches back less than 17 years. "Whether this is an omen of long-term sunspot decline, analogous to the Maunder Minimum, remains to be seen," they caution in a recent EOS article.

One thing is certain. Solar Minimum is a lot more interesting than it sounds: more.

JUPITER UPDATE: A little more than a month after a mystery-object crashed into Jupiter, the debris cloud is still visible in backyard telescopes. Amateur astronomer Brian Combs of Buena Vista, Georgia, took this picture on August 19th:

When Australian astrophotographer Anthony Wesley discovered the debris cloud on July 19th, it was about the size of many other small storms dotting Jupiter's upper atmosphere. Since then, the compact black mark has expanded into an enormous swirl rivaling the girth of the Great Red Spot itself. Unfortunately, as the cloud has expanded it has also faded, and its pale markings could soon disappear altogether. Continued monitoring is encouraged.

more images: from Abe Megahed of Madison, Wisconsin; from Ralf Vandebergh of the Netherlands


August 2009 Aurora Gallery
[previous Augusts: 2008, 2007, 2006, 2005, 2004, 2003, 2002, 2001]


2009 Perseid Photo Gallery
[Science@NASA: The Perseids are Coming, Horse Flies and Meteors]


Explore the Sunspot Cycle

       
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 23, 2009 there were 1068 potentially hazardous asteroids.
August 2009 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2009 MC9
Aug. 7
70.3 LD
16
1.2 km
2009 OF
Aug. 8
15.4 LD
18
220 m
2007 RQ17
Aug. 9
8.4 LD
17
130 m
2000 LC16
Aug. 17
75.6 LD
14
2.0 km
2006 SV19
Aug. 21
59.2 LD
16
1.3 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.
STEREO
  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...
   
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