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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 599.5 km/sec
density: 6.9 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B6
1939 UT Feb04
24-hr: B9
1220 UT Feb04
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 04 Feb 11
New sunspot 1152 is growing rapidly, but it does not yet pose a threat for strong flares. Credit: SDO/HMI
Sunspot number: 32
What is the sunspot number?
Updated 03 Feb 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 03 Feb 2011

The Radio Sun
10.7 cm flux: 80 sfu
explanation | more data
Updated 03 Feb 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 6 storm
24-hr max: Kp= 6
explanation | more data
Interplanetary Mag. Field
Btotal: 11.5 nT
Bz: 4.3 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 04 Feb 11
A solar wind stream flowing from the indicated coronal hole should reach Earth on Feb. 4th. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Feb 04 2200 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: 2011 Feb 04 2200 UTC
0-24 hr
24-48 hr
40 %
20 %
25 %
05 %
05 %
01 %
High latitudes
0-24 hr
24-48 hr
50 %
20 %
20 %
10 %
10 %
01 %
Friday, Feb. 4, 2011
What's up in space

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Satellite flybys

AURORA ALERT: A solar wind stream hit Earth's magnetic field during the late hours of Feb. 4th, sparking a G2-class (Kp=6) geomagnetic storm, in progress. High-latitude sky watchers should be alert for auroras, especially during the hours around local midnight.

Current aurora images: from Cristina Albuerne of Gimsøy, Lofoten, Norway; from Beate Kiil Karlsen of Norway;

CLOSE-APPROACHING ASTEROID: A small (4-5 meter) asteroid discovered earlier today by R. A. Kowalski of the Catalina Sky Survey will pass by Earth on Feb. 4th around 19:40UT at a distance of 11855 km. 2011 CQ1 will not hit Earth, but it will pass well inside the Clarke Belt of geosynchronous satellites. [more]

AFTER THE STORM: US skies are clearing in the aftermath of this week's monster winter storm. But "clear" is not the same as "empty." Sky watchers are seeing an unusual number of sundogs. Doug Koehler photographed these yesterday in Davenport, Iowa:

"These brilliant sundogs appeared in the early morning sub-zero fog just off the Mississippi river," says Koehler. "They lasted about 20 minutes before fading away. The camera doesn't do justice to how colorful they were."

Sundogs and their cousins, sun pillars, are caused by ice crystals in the air. And if there's one thing North Americans have a lot of, it's icy air. Indeed, the dog and pillar show is likely to continue for at least six more weeks.

more images: from Dave Merritt of Middletown, Indiana; from Sid Murthy of Laramie, Wyoming; from Patty of Davenport, Iowa

SOLAR SAIL FLARES: NASA's new solar sail, NanoSail-D, is circling Earth and attracting the attention of sky watchers--especially when it flares. Sunlight glinting off the sail's reflective fabric can rival the brightest stars, making a sudden and luminous streak across the night sky. Here it is over Rautalampi, Finland, on Jan. 30th:

Photo details: Nikon D70s, 18 mm/f/3.5, ISO 1600, 30 sec exposures

"At its peak, the flare was magnitude +3.5, easily seen with the naked eye," says photographer Vesa Vauhkonen. "I was able to photograph the event using an ordinary digital camera (a Nikon D70s)."

On the same night, NanoSail-D flared even more brightly over Helsinki, Finland. A meteor camera operated by Esko Lyytinen caught the sail flashing almost three times brighter than a 1st magnitude star: image.

Future flares could dwarf these. NanoSail-D is skimming the top of Earth's atmosphere and slowly descending as it circles the planet. As the spacecraft gets closer to Earth and aerodynamic forces flatten the fabric into an ever-better reflector, flares are likely to intensify, theoretically exceeding the brightness of Venus as much as 100-fold (5 magnitudes). Photograph one of those and you just might win $500.

more images: from Enzo De Bernardini of Buenos Aires, Argentina; from Arto Oksanen of Jyväskylä, Finland; from Mika Järvinen of Finland

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

  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 4, 2011 there were 1191 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
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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