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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 454.4 km/sec
density: 2.8 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Sep04
24-hr: A0
1650 UT Sep04
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 04 Sept. 09
The sun is blank--no sunspots.. Photo credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 03 Sept 2009

Spotless Days
Current Stretch: 2 days
2009 total: 195 days (79%)
Since 2004: 706 days
Typical Solar Min: 485 days
explanation | more info
Updated 03 Sept 2009

Far side of the Sun:
This holographic image reveals a possible sunspot on the far side of the sun--but it is not real. It is a noisy artifact of the data processing. The sun remains blank. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 2.2 nT
Bz: 0.4 nT north
explanation | more data
Updated: Today at 2345 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: 2009 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: 2009 Sep 04 2201 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
10 %
05 %
01 %
01 %
01 %
01 %
What's up in Space
September 4, 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.


ARE SUNSPOTS DISAPPEARING? The sun is in the pits of the deepest solar minimum in nearly a century. Weeks and sometimes whole months go by without even a single tiny sunspot. Are sunspots disappearing? Experts discuss the question in today's story from Science@NASA.

BUZZING ANDROMEDA: Residents of the Andromeda galaxy experienced a close encounter on Sept. 3rd. That's when Ugur Ikizler of Bursa, Turkey, photographed a spaceship streaking past the great spiral:

Photo details: Canon Rebel XT, Hutech modified, ISO 800, 39 sec

It was the International Space Station (ISS).

The International Space Station is streaking among the stars of the night sky with space shuttle Discovery in tow. Discovery is visiting the ISS to deliver a load of laboratory equipment. The new hardware will kickstart onboard research in low-gravity fluid physics, crystal growth and semiconductor development, among other things. Buzzing Andromeda was purely extracurricular.

What will the two spaceships encounter next? See for yourself. The Simple Satellite Tracker tells when to look.

SOLAR MINIMUM VS. GLOBAL WARMING: From 2002 to 2008, decreasing solar irradiance has countered much anthropogenic warming of Earth's surface. That's the conclusion of researchers Judith Lean (NRL) and David Rind (NASA/GISS), who have just published a new analysis of global temperatures in the Geophysical Research Letters. Lean and Rind considered four drivers of climate change: solar activity, volcanic eruptions, ENSO (El Nino), and the accumulation of greenhouse gases. The following plot shows how much each has contributed to the changing temperature of Earth's surface since 1980:

Volcanic aerosols are a source of cooling; ENSO and greenhouse gases cause heating; the solar cycle can go either way. When added together, these factors can account for 76% of the variance in Earth's surface temperature over the past ~30 years, according to the analysis of Lean and Rind.

Several aspects of their model attract attention: "The warmest year on record, 1998, coincides with the 'super-El Nino' of 1997-98," points out Lean. "The ESNO is capable of producing significant spikes in the temperature record." Solar minimum has the opposite effect: "A 0.1% decrease in the sun's irradiance has counteracted some of the warming action of greenhouse gases from 2002 - 2008," she notes. "This is the reason for the well-known 'flat' temperature trend of recent years."

What's next? Ultimately, the authors say, temperatures will begin rising again as greenhouse gases accumulate and solar activity resumes with the coming of the next solar cycle. Of couse, the solar cycle could be out of whack; if solar minimum deepens and persists, no one is certain what will happen. Lean and Rind reveal their predictions for the future here.

Reference: Lean, J. L., and D. H. Rind (2009), How will Earth's surface temperature change in future decades?, Geophys. Res. Lett., 36, L15708

August 2009 Aurora Gallery
[previous Augusts: 2008, 2007, 2006, 2005, 2004, 2003, 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 4, 2009 there were 1068 potentially hazardous asteroids.
August 2009 Earth-asteroid encounters:
Miss Distance
2009 MC9
Aug. 7
70.3 LD
1.2 km
2009 OF
Aug. 8
15.4 LD
220 m
2007 RQ17
Aug. 9
8.4 LD
130 m
2000 LC16
Aug. 17
75.6 LD
2.0 km
2006 SV19
Aug. 21
59.2 LD
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.
  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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