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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 386.5 km/sec
density: 1.3 protons/cm3
explanation | more data
Updated: Today at 2341 UT
X-ray Solar Flares
6-hr max: C1
1836 UT Feb21
24-hr: C7
1012 UT Feb21
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 21 Feb 11
NOAA forecasters estimate a 60% chance of M-class flares from sunspot complex 1161-1162 during the next 24 hours. Credit: SDO/HMI
Sunspot number: 103
What is the sunspot number?
Updated 20 Feb 2011

Spotless Days
Current Stretch: 0 days
2011 total: 1 day (2%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 820 days
Typical Solar Min: 486 days

Updated 20 Feb 2011


The Radio Sun
10.7 cm flux: 105 sfu
explanation | more data
Updated 20 Feb 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 5.7 nT
Bz: 2 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 18 Feb 11
There are no large equatorial coronal holes on the Earth-side of the sun. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Feb 21 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
50 %
50 %
CLASS X
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 Feb 21 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
10 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
10 %
10 %
SEVERE
01 %
01 %
 
Monday, Feb. 21, 2011
What's up in space
 

They came from outer space--and you can have one! Genuine meteorites are now on sale in the Space Weather Store. They make a unique Valentine's gift.

 
Own your own meteorite

SPACE WEATHER IN A GADGET-DRIVEN WORLD: Authorities in Washington DC caused a stir over the weekend when they announced at the annual AAAS meeting that high-tech modern society is increasingly vulnerable to solar storms. "The last time we had a maximum in the solar cycle, the world was a very different place," noted NOAA administrator Jane Lubchenco. "Cell phones are now ubiquitous [and we] rely on them for so many different things." Others noted a myriad of GPS-dependent technologies that could be brought down by a strong solar flare. This is old news to many readers of spaceweather.com. Nevertheless, the web is abuzz with reports from the meeting.

BIG SUNSPOTS: Sunspot complex 1161-1162 quieted down over the weekend, producing few intense flares. Could it be the quiet before the storm? The tempestuous appearance of the region suggests more action could be in the offing. Rogerio Marcon sends this picture from his backyard observatory in Campinas SP Brasil:

Marcon recorded the image using an H-alpha filter tuned to the red glow of solar hydrogen. It reveals several dark magnetic cores, each larger than Earth itself, interconnected by turbulent arcs of magnetized plasma. Similar filters are now available in the Space Weather Store for readers who would like to see these 'spots with their own (safely filtered) eyes.

NOAA forecasters estimate a 60% chance of M-class solar flares during the next 24 hours. Stay tuned for action.

more images: from Pavol Rapavy of Observatory Rimavska Sobota, Slovakia; from Andy Burns of El Bosque, Sierra de Cadiz, Spain; from Raymond Lalonde of Cornwall, Ont, Canada; from Jan Timmermans of Valkenswaard, The Netherlands; from Luca Tesoro of Mercogliano (AV), Italy;

FLICKERING SOLAR SAIL: NASA has joined forces with Spaceweather.com to stage a solar sail photography competition. Top prize: $500. Peter Rosen hasn't won yet, but with this movie of NanoSail-D, he has definitely entered the contest:


Photo details: Canon EOS 5D Mk II, 85/1.2 lens @ 1.2, 55 one-sec exposures at ISO 3200.

Not to be confused with the airliner at the top of the photo, NanoSail-D is the star-like object below denoted by a cross. Watch the movie again and note how the sail flickers in the inset circle.

Rosen describes what happened: "I photographed NanoSail-D from Stockholm, Sweden, on Feb. 4th. The sail was very low on the horizon, but I was able to catch it using my Canon EOS 5D digital camera. I estimate its magnitude between +6 and +7."

"There are many other satellites in the field of view and some airplanes coming in for landing at the local airport," he continues. "NanoSail-D behaves very differently from other satellites as its visibility seems to pulsate in short flashes sometimes several per second. This image zooms in on the phenomenon. I wonder if it due to small changes in the sail's direction and thus reflectivity?"

Indeed, sunlight is almost certainly glinting off the sail's reflective fabric. Researchers believe these flickers could, from time to time, develop into spectacular flares, outshining the brightest stars and perhaps even exceeding the luminosity of Iridium flares. At the moment, these flares are unpredictable because the sail's orientation is not known precisely enough to forecast sun-glints. The only way to catch one is to go outside and look.

NanoSail-D flyby times: on the web, on your cell phone.

NEW: NanoSail-D Photo Gallery
[NASA: Solar Sail Stunner] [Photo Contest]


February 2011 Aurora Photo Gallery
[previous Februaries: 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 February 21, 2011 there were 1198 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 CD66
Feb 13
7.2 LD
--
18 m
2011 CL50
Feb 19
6.2 LD
--
13 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
2002 JC
Jun 1
57.5 LD
--
1.6 km
2009 BD
Jun 2
0.9 LD
--
9 m
2002 JB9
Jun 11
71.5 LD
--
3.2 km
2001 VH75
Jun 12
42.2 LD
--
1.1 km
2004 LO2
Jun 15
9.9 LD
--
48 m
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.
STEREO
  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
Heliophysics
  the underlying science of space weather
Conquest Graphics
  for out-of-this-world printing and graphics
Science Central
   
  more links...
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