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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 514.3 km/sec
density: 2.1 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: B1
2108 UT Feb01
24-hr: B3
0013 UT Feb01
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 01 Feb 11
Sunspot 1150 is still growing, but otherwise remains quiet---no big flares. Credit: SDO/HMI
Sunspot number: 21
What is the sunspot number?
Updated 31 Jan 2011

Spotless Days
Current Stretch: 0 days
2011 total: 1 day (3%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 820 days
Typical Solar Min: 486 days

Updated 31 Jan 2011

The Radio Sun
10.7 cm flux: 81 sfu
explanation | more data
Updated 31 Jan 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 4
explanation | more data
Interplanetary Mag. Field
Btotal: 3.5 nT
Bz: 0.1 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 01 Feb 10
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about Feb. 3rd. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Feb 01 2200 UTC
0-24 hr
24-48 hr
05 %
05 %
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 Feb 01 2200 UTC
0-24 hr
24-48 hr
60 %
35 %
10 %
50 %
05 %
15 %
High latitudes
0-24 hr
24-48 hr
60 %
20 %
20 %
60 %
10 %
20 %
Tuesday, Feb. 1, 2011
What's up in space

Metallic photos of the sun by renowned photographer Greg Piepol bring together the best of art and science. Buy one or a whole set. They make a stellar gift.

Metallic pictures of the Sun

SOLAR SAIL FLARES: NASA's first Earth-orbiting solar sail, NanoSail-D, is circling our planet and attracting the attention of sky watchers. Occasionally, sunlight glinting from the sail's reflective fabric produces a flash of light in the night sky. These "solar sail flares" are expected to grow brighter as NanoSail-D descends in the weeks ahead. Get the full story from Science@NASA.

AURORA-BURST: According to the official forecast, the odds of geomagnetic activity on Jan. 31st were less than 10%. That was good enough for Kjetil Skogli of Troms, Norway. "We went out to look in spite of the low expectations--and there it was!" An aurora-burst was in progress directly overhead:

"We didnt have to wait at all," says Skogli. "The show started right away and lasted for more than an hour with a lot of moving green curtains and rays."

The unexpected display was caused by a disturbance in the interplanetary magnetic field (IMF) near Earth. The IMF tilted south, opening a hole in Earth's magnetosphere. Solar wind poured in and ignited the auroras.

More auroras are in the offing. A solar wind stream is heading for Earth, due to arrive on Feb. 2nd and 3rd. NOAA forecasters peg the chances of geomagnetic activity on those dates at 20% to 35%--much better odds than Skogli had. High-latitude sky watchers should be alert for auroras.

January 2011 Aurora Photo Gallery
[previous Januaries: 2010, 2009, 2008, 2007, 2005, 2004]

SNOW SPIRALS: As a winter storm of historic proportions prepares to sweep across the USA later this week, midwesterners should be alert for some unaccustomed sights. One of them is snow spirals. Michael French photographed this specimen in Frederick, Maryland, on Jan. 29th:

"I call them Karra Spirals, after my wife Karra Strickland who discovered them in our yard," says French. "They were all over town, spiraling down the braided metal guy-wires on telephone poles. Here's the curious thing: The wires were spun clockwise, while the snow formations were spun anti-clockwise. The hardened snow spirals were rotated opposite of the metal wire's weave. We also noticed that spirals near the top of the wires were longer (~1 meter) than spirals at the bottom (0.1 - 0.3 meters)--perhaps because of gravity?"

Indeed, the changing wavelength of the spiral suggests gravity played a role in their formation. This could be how heavy snow sags under its own weight when it clings to a braided wire. Why the spirals should oppose the braid, however, is not obvious. Readers with explanations are invited to submit them for consideration.

Solar Eclipse Photo Gallery
[NASA: Hinode Observes Annular Solar Eclipse]

  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 February 1, 2011 there were 1191 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 BW11
Jan 25
0.3 LD
9 m
2011 AL37
Jan 26
2.2 LD
60 m
2011 BF10
Jan 30
9.1 LD
14 m
2011 BG24
Jan 30
5.9 LD
23 m
2011 BE24
Feb 3
9.3 LD
35 m
2003 YG118
Feb 20
67.7 LD
1.8 km
2000 PN9
Mar 10
45.5 LD
2.6 km
2002 DB4
Apr 15
62.5 LD
2.2 km
2008 UC202
Apr 27
8.9 LD
10 m
2009 UK20
May 2
8.6 LD
23 m
2008 FU6
May 5
75.5 LD
1.2 km
2003 YT1
May 5
65.3 LD
2.5 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
  more links...
©2010 All rights reserved. This site is penned daily by Dr. Tony Phillips.
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