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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 557.9 km/sec
density: 1.8 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Sep04
24-hr: A0
1310 UT Sep04
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 04 Sep 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 03 Sept. 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= 2 quiet
24-hr max: Kp= 6
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 3.5 nT
Bz: 1.0 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 Sep 04 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 Sep 04 2201 UTC
0-24 hr
24-48 hr
50 %
25 %
25 %
15 %
10 %
05 %
High latitudes
0-24 hr
24-48 hr
50 %
30 %
30 %
20 %
15 %
10 %
What's up in Space
September 4, 2008
AURORA ALERTS: Did you miss the Northern Lights of August 9th? Next time get a wake-up call from Space Weather PHONE.  

JULES VERNE: Europe's robotic cargo carrier, ATV Jules Verne, is scheduled to undock from the International Space Station on Sept. 5th. The ATV is wrapping up a successful five-month mission, delivering supplies, reboosting the ISS, and serving as an impromptu bedroom for the ISS crew. On Sept. 29th, ESA mission controllers plan to send Jules Verne into Earth's atmosphere where it will disintegrate as a fireball over the Pacific Ocean. Stay tuned to the Satellite Tracker for viewing opportunities.

AURORA ALERT: A solar wind stream is buffeting Earth's magnetic field and causing auroras around the Arctic Circle. "Lights danced most of the night until the sky got cloudy at 2:30 a.m.," reports Yuichi Takasaka, who sends this picture from Yellowknife in the Northwest Territories of Canada:

The coronal hole on the sun responsible for this activity is a broad one, which means the solar wind could blow unabated for days. NOAA forecasters estimate a 10% chance of geomagnetic storms during the next 24 hours; high-latitude sky watchers should remain alert for auroras.

September 2008 Aurora Gallery
[Past Septembers: 2007, 2006, 2005, 2004, 2002, 2001]

AUGUST SUNSPOTS: Contrary to reports, August 2008 was not the first month since June 1913 without a sunspot. August did have a sunspot, and here it is:

This is a bipolar active region that appeared on Aug. 21st. Pavol Rapavy took the picture from his backyard observatory in Rimavska Sobota, Slovakia. Because the sunspot lasted a short time, NOAA did not assign it a number. Nevertheless, the solar index World Data Center in Belgium recognizes the spot with a non-zero sunspot count on Aug. 21st and 22nd.

There has been much speculation in the solar "blogosphere" about the length of the ongoing solar minimum. The sun has been mostly blank for a long time and people are wondering when the next solar cycle is going to begin. Some observers claim we're entering a climate-altering minimum of historic proportions.

There's no evidence to back up these claims. As far as anyone can tell, the ongoing solar minimum is historically normal. New cycle spots are slowly beginning to appear and, indeed, the disputed sunspot of August is one of them. Its magnetic polarity places it in Solar Cycle 24 expected to peak in 2011 or 2012. If the sun remains blank for another year, it's time to re-think our assurances, but for now, all is well.

Who knew the blank sun could be so interesting?

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 4, 2008 , there were 977 potentially hazardous asteroids.
Sept. 2008 Earth-asteroid encounters:
Miss Distance
2003 WT153
Sept. 7
5.8 LD
11 m
1996 HW1
Sept. 12
53 LD
3.7 km
2003 SW130
Sept. 19
8.6 LD
7 m
1998 UO1
Sept. 26
25 LD
2.0 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.
  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
  a one-stop web hub for all things scientific
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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