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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 424.0 km/sec
density: 1.4 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Sep16
24-hr: A0
0535 UT Sep16
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 16 Sept. 09
The Earth-facing side of the sun is blank--no sunspots.. Photo credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 15 Sept 2009

Spotless Days
Current Stretch: 14 days
2009 total: 207 days (81%)
Since 2004: 718 days
Typical Solar Min: 485 days
explanation | more info
Updated 15 Sept 2009

Far side of the Sun:
This holographic image reveals a growing active region on the far side of the sun. It is located at latitude 30-deg south, making it a probable member of Solar Cycle 24. Image credit: Global Oscillation Network Group
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 4.8 nT
Bz: 1.7 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 as early as Sept. 17th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Sep 16 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: 2009 Sep 16 2201 UTC
0-24 hr
24-48 hr
15 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
05 %
01 %
01 %
01 %
01 %
What's up in Space
September 16, 2009

AURORA ALERT: Did you miss the Northern Lights? Next time get a wake-up call: Spaceweather PHONE.


IN SEARCH OF DARK ASTEROIDS: NASA is set to launch a sensitive new infrared space telescope to search for dark asteroids that could pose a threat to Earth. Get the full story from Science@NASA.

FARSIDE SUNSPOT: A big sunspot appears to be growing on the far side of the sun. Yesterday, the National Solar Observatory's GONG network detected helioseismic echoes from the sunspot's gathering magnetic field. Today, NASA's STEREO-B spacecraft is beaming back images of an active region peeking over the sun's far-eastern limb--exactly where GONG data predicted it would be:

Photo credit: STEREO-B Extreme UV Telescope

Irene Gonzalez-Hernandez, a solar physicist working on the GONG project, says "I believe this is a large active region belonging to new Solar Cycle 24. The sun's rotation should turn it toward Earth for direct viewing on Sept. 20th."

Until then, the sunspot number remains pegged at zero. Why? Because farside sunspots do not count. Back in the 19th century when the sunspot number was invented, astronomers had no way of monitoring events on the farside of the sun, so no provision was made for adding farside spots to the total. Fast forward to 2009: NASA has two spacecraft (STEREO-A and -B) maneuvering for a 360o view of the entire sun, and by the year 2011 no sunspot will escape their detection. A more modern way of counting sunspots may soon be required.

Readers, if you have a solar telescope, monitor the eastern limb for coming attractions.

MORNING SHOW: Around the world, today, early risers witnessed a beautiful sunrise display when Venus and the Moon rose side-by-side in the eastern sky just ahead of the sun. Azhy Chato Hasan sends this snapshot from Erbil city in the Kurdistan region of Iraq:

Photo details: Nikon D50, 70-300mm,f/5, 1 sec, 800 ISO

"The weather was perfect--no wind or dust, and very few clouds," says Hasan. "I found myself in the middle of a very quiet, tree-lined street and took the picture using my Nikon D50 digital camera. It was a bright and beautiful display."

more images: from Tamas Ladanyi of Veszprem (Hungary); from Michel Renaud of Boisbriand, Quebec, Canada; from Yuichi Takasaka of Yellowknife, Northwest Territories, Canada; from Zlatko Pasko of Stara Pazova, Serbia; from Adrian New of San Antonio, Texas; from P-M Hedén of Vallentuna, Sweden; from Mike Evans of San Diego, California; from Alan Dyer of Gleichen, Alberta, Canada; from Mike Rosset of Jacksonville, Florida; from John Elliott of Bellevue, Washington; from Martin Mc Kenna of Maghera, N. Ireland

Sept. 2009 Aurora Gallery
[previous Septembers: 2008, 2007, 2006, 2005, 2004, 2002, 2001]

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 September 16, 2009 there were 1070 potentially hazardous asteroids.
Sept. 2009 Earth-asteroid encounters:
Miss Distance
2009 QC35
Sept. 2
2.9 LD
35 m
2009 HD21
Sept. 29
22.9 LD
1.0 km
1998 FW4
Sept. 29
8.6 LD
550 m
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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