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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 291.7 km/sec
density: 0.4 protons/cm3
explanation | more data
Updated: Today at 2331 UT
X-ray Solar Flares
6-hr max: C2
1822 UT Sep01
24-hr: C2
1822 UT Sep01
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 01 Sep 11
The sun is peppered with sunspot groups, several posing a threat for C-class flares. Credit: SDO/HMI
Sunspot number: 121
What is the sunspot number?
Updated 31 Aug 2011

Spotless Days
Current Stretch: 0 days
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 821 days
Typical Solar Min: 486 days

Updated 31 Aug 2011

The Radio Sun
10.7 cm flux: 109 sfu
explanation | more data
Updated 31 Aug 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 1
explanation | more data
Interplanetary Mag. Field
Btotal: 2.7 nT
Bz: 2.4 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 01 Sep 11
A solar wind stream flowing from the indicated coronal hole could reach Earth on or about Sept. 4th. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Sep 01 2200 UTC
0-24 hr
24-48 hr
15 %
15 %
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: 2011 Sep 01 2200 UTC
0-24 hr
24-48 hr
10 %
20 %
01 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
25 %
01 %
10 %
01 %
01 %
Thursday, Sep. 1, 2011
What's up in space

Are we alone? Your iPhone has the answer. Download the all-new Drake Equation app to calculate the population of the Milky Way.

DrakeEQ for iPhone and iPad

LOTS OF SUNSPOTS, NOT MUCH ACTIVITY: The solar disk is peppered with sunspot groups, at least eight of them. None of them, however, are producing strong flares. Solar activity remains generally low.

GIANT SINE WAVE: Imagine a sine wave 400,000 km long. Today, NASA's Solar Dynamics Observatory is monitoring just such a structure. It's an enormous filament of magnetism slithering over the sun's northeastern limb:

One of the wave troughs appears to be passing through the core of sunspot 1283. If so, an eruption of the sunspot could have an interesting ripple effect on the greater filament, perhaps even causing it to collapse. Readers with solar telescopes are encouraged to monitor this region so full of possibilities. (Note: An earlier version of this news item mislabeled the sunspot--it said "1282" when in fact "1283" is the correct active region.)

A COMET AMONG THE STARS: As September begins, green Comet Garradd is gliding across the star fields of the Milky Way in the early evening sky. The icy visitor from tthe outer solar system is not yet visible to the naked eye, but it looks great through amateur telescopes (recommended: The Comet Hunter). Maximilian Teodorescu sends this picture from his backyard observatory in Comana, Romania:

"I took the picture using my 8-inch telescope--a 34 minute exposure at ISO 6400," says Teodorescu. "The comet looks so nice in front of the Milky Way."

Astrophotographer Pete Lawrence of Selsey UK points out that Comet Garradd is approaching Brocchi's Cluster--also known as "the Coathanger." Lawrence photographed the approach on August 31st. "The best night for a photo opportunity between Garradd and The Coathanger is on the 2nd of September leading into the morning of the 3rd, when the comet will pass very close to the hook of the hanger."

At the moment, Comet Garradd is a purely telescopic object. It is, however, approaching the sun and brightening. Recent projections place it at peak magnitude 6, on the threshold of naked-eye visibility, in February 2012. Because Comet Garradd is a first-time visitor to the inner solar system, it could behave in unexpected ways, perhaps exceeding those expectations. Stay tuned--and meanwhile browse the image links below.

more images: from Parks Squyres of SaddleBrooke, Arizona; from Chris Schur of Payson, Arizona; from Tamas Abraham of Zsambek, Hungary

comet links: finder charts, 3D orbit.

August 2011 Aurora Gallery
[previous Augusts: 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002]

  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 1, 2011 there were 1244 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 QF48
Aug 27
3.4 LD
36 m
2003 QC10
Sep 18
50 LD
1.2 km
2004 SV55
Sep 19
67.5 LD
1.2 km
2007 TD
Sep 23
3.8 LD
58 m
2002 AG29
Oct 9
77.1 LD
1.0 km
2000 OJ8
Oct 13
49.8 LD
2.5 km
2009 TM8
Oct 17
1.1 LD
8 m
2011 FZ2
Nov 7
75.9 LD
1.6 km
2005 YU55
Nov 8
0.8 LD
175 m
1994 CK1
Nov 16
68.8 LD
1.5 km
1996 FG3
Nov 23
39.5 LD
1.1 km
2003 WM7
Dec 9
47.6 LD
1.5 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 web 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 Dynamics Observatory
  Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever.
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Solar and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
Daily Sunspot Summaries
  from the NOAA Space Environment Center
  the underlying science of space weather
Science Central
Conquest Graphics
  for out-of-this-world printing and graphics
Trade Show Displays
  more links...
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