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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 351.7 km/sec
density: 0.1 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: C2
2253 UT Nov07
24-hr: C3
0310 UT Nov07
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 07 Nov 11
Sunspot 1339 has a delta-class magnetic field that harbors energy for X-class solar flares. Credit: SDO/HMI
Sunspot number: 144
What is the sunspot number?
Updated 06 Nov 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 06 Nov 2011

The Radio Sun
10.7 cm flux: 177 sfu
explanation | more data
Updated 06 Nov 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 3
explanation | more data
Interplanetary Mag. Field
Btotal: 8.3 nT
Bz: 1.1 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 07 Nov 11
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Nov 07 2200 UTC
0-24 hr
24-48 hr
70 %
70 %
10 %
10 %
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 Nov 07 2200 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
Monday, Nov. 7, 2011
What's up in space

Turn your cell phone into a field-tested satellite tracker. Works for Android and iPhone.

Satellite flybys

CHANCE OF FLARES: Big sunspot 1339 has quieted since a flurry of M-flares on Saturday, but the active region still poses a threat for strong eruptions. NOAA forecasters estimate a 70% chance of M-flares and a 10% chance of X-flares during the next 24 hours. Solar flare alerts: text, voice.

ASTEROID FLYBY: NASA radars are monitoring 2005 YU55, an asteroid the size of an aircraft carrier, as it heads for a Nov. 8th flyby of the Earth-Moon system. There is no danger to our planet. At closest approach on Tuesday at 3:28 pm PST (23:28 UT), the 400m-wide space rock will be 324,600 kilometers away, about 85% the distance from Earth to the Moon.

Professional astronomers are eagerly anticipating the flyby as the asteroid presents an exceptionally strong radar target. Powerful transmitters at Goldstone and Arecibo will ping the space rock as it passes by, revealing the asteroid's shape and texture in crisp detail, and pinpointing its orbit for future flyby calculations. A movie from JPL explains:

Asteroids this big have passed by Earth at similar distances many times before, but this is the first time astronomers have known about the flyby in advance. For instance, a similar encounter occurred in 1976 when 2010 XC15 split the distance between Earth and the Moon. Researchers didn't discover that space rock until 24 years after the flyby. The Nov. 8, 2011, passage of 2005 YU55 thus represents a rare opportunity for asteroid research.

Experienced amateur astronomers should be able to photograph 2005 YU55 as it zips through the constellations Aquila and Pegasus glowing like an 11th magnitude star. Even under the full moonlight of Nov. 8th, such a bright asteroid is within reach of mid-sized backyard telescopes. The timing of the flyby favors observers in western Europe and eastern parts of North America. Check Sky & Telescope for observing tips or go straight to JPL for the object's ephemeris.

FINE SUNSPOT: The emergence of giant sunspot AR1339 has had an unexpected effect on Earth. Instead of a rash of geomagnetic storms, there has been a rash of fine photography. Kamila M of Puławy, Poland, framed the sunspot in black and white at sunset on Nov. 6th:

The color version is not bad either. "It was a fight with the light!" says Kamila.

The sheer size of the sunspot (it is three times wider than Earth and almost ten times as long) makes it an easy target not only for backyard solar telescopes but also for off-the-shelf digital cameras. A bit of natural filtering provided by sunset clouds and haze is all a photographer needs to turn a gnarly-edged sunspot into art. Browse the links below for more examples.

fine sunspot shots: from Jim Saueressig II of Burlington, Kansas; from Marek Nikodem of Szubin, Poland;

October 2011 Aurora Gallery
[previous Octobers: 2010, 2009, 2008, 2007, 2006, 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 November 7, 2011 there were 1256 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 FZ2
Nov 7
75.9 LD
1.6 km
2005 YU55
Nov 8
0.8 LD
400 m
2011 UT91
Nov 15
9.9 LD
109 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
1.6 km
1999 XP35
Dec 20
77.5 LD
1.0 km
2000 YA
Dec 26
2.9 LD
80 m
2011 SL102
Dec 28
75.9 LD
1.1 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
Trade Show Displays
  more links...
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