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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 514.6 km/sec
density: 0.1 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: B4
1942 UT Mar18
24-hr: C1
0237 UT Mar18
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 18 Mar 12
New sunspot 1435 is growing rapidly and could soon pose a threat for solar flares. Credit: SDO/HMI
Sunspot number: 89
What is the sunspot number?
Updated 17 Mar 2012

Spotless Days
Current Stretch: 0 days
2012 total: 0 days (0%)
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 17 Mar 2012


The Radio Sun
10.7 cm flux: 102 sfu
explanation | more data
Updated 17 Mar 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 4
unsettled
explanation | more data
Interplanetary Mag. Field
Btotal: 4.1 nT
Bz: 1.1 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 18 Mar 12
Earth is inside a solar wind stream flowing from this coronal hole. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2012 Mar 18 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
15 %
15 %
CLASS X
05 %
05 %
Geomagnetic Storms:
Probabilities for significant disturbances in Earth's magnetic field are given for three activity levels: active, minor storm, severe storm
Updated at: 2012 Mar 18 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
30 %
05 %
MINOR
15 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
20 %
10 %
SEVERE
15 %
05 %
 
Sunday, Mar. 18, 2012
What's up in space
 

Don't just watch shooting stars. Wear them! Authentic meteorite jewelry for Valentine's Day is now available in the SpaceWeather Store.

 
Meteorite jewelry

FARSIDE CME: A spectacular CME rocketed away from the sun's northwestern limb during the early hours of March 18th: movie. The probable source was old sunspot AR1429, still active as it transits the far side of the sun. Earth will not be affected by the cloud.

ST. PATRICK'S DAY, SWEDEN-STYLE: "BBQ - check. Great mates - check. Guiness - check. Northern Lights - check. We had it all last night!" says Neal Cheeseman of Arvidsjaur, Sweden, who celebrated St. Patrick's Day as shown below:

"Happy St. Patricks Day (Sweden Style) everybody!"

The night after St. Patrick's Day might be just as green. NOAA forecasters estimate a 35% chance of high-latitude geomagnetic storms as a high-speed solar wind continues to buffet Earth's magnetic field. Aurora alerts: text, phone.

more images: from Jónína Óskarsdóttir of Faskrudsfjordur, Iceland; from Peter Scott of Durness, Scotland, UK; from Francis Anderson of Tuktoyaktuk, Northwest Territories Canada; from Chad Blakley of Abisko National Park, Sweden; from Iurie Belegurschi of Iceland; from Dirk Obudzinski of Cleary Summit, Alaska; from Petra Schneider of Reykjanes peninsula, Iceland; from Greg Kretovic of AuTrain, Michigan;

SCINTILLATION SQUIGGLES: Everyone knows that stars twinkle but planets do not. The reason has to do with angular size. Stars are distant pinpricks smaller than the thermal irregularities in Earth's atmosphere that refract their light. Each packet of air that passes in front of a star produces a well-defined change in color or brightness. Planets, on the other hand, are relatively nearby and wide; they span many atmospheric irregularities, which tends to smooth out the prismatic action.

Photographer Monika Landy-Gyebnar of Veszprem, Hungary, has found a kinetic way to demonstrate the effect. "When photographing a star or planet, kick the tripod during the exposure." She's applied this technique to many stars and planets, and the resulting collection of squiggles reveals the character of their twinkles:

"If we take a photo of a star with a shaking camera, the result is a wavy line with many colors," she points out. "If we photograph a planet, however, there is no change; the color and width of the squiggle are nearly constant."

The scintillation effect is greatest for stars near the horizon, which must shine through a greater distance of turbulent atmosphere. Angles noted in the image above are altitudes. The lowest-hanging stars display the strongest and most colorful twinkling.

"Demonstrating this is a 'must-do' thing when you give a lecture or show on astronomical observations for novices," she concludes. Observing tips and more of Landy-Gyebnar's "scintillation squiggles" may be found here.


February 2012 Aurora Gallery
[previous Februaries: 2011, 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 March 18, 2012 there were 1287 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2012 FG
Mar 14
1.6 LD
--
28 m
2012 EN5
Mar 15
1.4 LD
--
15 m
2012 EL8
Mar 16
7.3 LD
--
10 m
2011 YU62
Mar 16
73.4 LD
--
1.3 km
2012 FM
Mar 18
8.3 LD
--
26 m
2012 EO8
Mar 21
3.6 LD
--
58 m
2012 EK5
Mar 22
5.8 LD
--
33 m
2012 EG5
Apr 1
0.6 LD
--
62 m
1996 SK
Apr 18
67.2 LD
--
1.6 km
2007 HV4
Apr 19
4.8 LD
--
8 m
2011 WV134
Apr 28
38.6 LD
--
1.6 km
1992 JD
May 2
9.5 LD
--
43 m
2010 KK37
May 19
2.3 LD
--
31 m
4183 Cuno
May 20
47.4 LD
--
5.7 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.
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
Trade Show Displays
   
  more links...
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