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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 464.8 km/sec
density: 6.2 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: B2
1822 UT Jun21
24-hr: C7
0326 UT Jun21
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 21 Jun 11
Sunspot 1236 produced a C7-class solar flare on June 21st. Credit: SDO/HMI
Sunspot number: 43
What is the sunspot number?
Updated 20 Jun 2011

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

Updated 20 Jun 2011


The Radio Sun
10.7 cm flux: 96 sfu
explanation | more data
Updated 20 Jun 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= 3
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 3.3 nT
Bz: 0.8 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 21 Jun 11
A solar wind stream flowing from the indicated coronal hole could reach Earth on June 23rd. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Jun 21 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
05 %
05 %
CLASS X
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 Jun 21 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
25 %
MINOR
01 %
30 %
SEVERE
01 %
15 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
20 %
MINOR
01 %
35 %
SEVERE
01 %
25 %
 
Tuesday, Jun. 21, 2011
What's up in space
 

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

 
Satellite flybys

CHANGE OF SEASONS: Today marks the beginning of northern summer. The change of seasons occurs on June 21st at precisely 17:16 UT (1:16 p.m. EDT) when the sun reaches its highest point on the celestial sphere. Because Earth's seasons are reversed in the two hemispheres, today is also the beginning of southern winter. Happy Solstice!

INCOMING: Magnetic fields above sunspot complex 1236 erupted during the early hours of June 21st, producing a C7-class solar flare and a full-halo CME. The expanding cloud is heading almost directly toward Earth:

UPDATE: According to analysts at the GSFC Space Weather Lab, the CME left the sun traveling 800 km/s and it will reach Earth on June 23rd at 23:22 UT (plus or minus 7 hours). A very cool 3D heliospheric model shows the cloud sweeping past our planet. The impact is expected to trigger a G2-class (Kp=6) geomagnetic storm.

High-latitude sky watchers should be alert for auroras on June 23rd and 24. The season favors southern hemisphere observers, where solstice skies are winter-dark. Aurora alerts: text, voice.

June 2011 Aurora Gallery
[Aurora alerts: text, voice] [previous Junes: 2010, 2008, 2001]

SOLSTICE SOLARGRAPHS: Last December, the staff of the Philippus Lansbergen Observatory in Middelburg, the Netherlands, invited members of the general public to join them for a solargraph-making party. A solargraph is a simple pinhole camera made from a soda or beer can lined with a piece of photographic paper. About a 100 cans were deployed around the observatory and, six months later, here are the results:

Each blue square shows the daily path of the sun across the skies of the Netherlands. The lowest arcs were traced by the winter sun of Dec. 2010. The highest arc was made by the sun just yesterday, June 19th, only two days before the 2011 summer solstice. Occasional gaps are caused by clouds.

"As you can see," says a member of the observatory staff, "we had one of the sunniest springs ever in our province. It was even sunnier than in southern Spain!"

6-month Solargraph How-to Guides: #1, #2, #3


June 15th Lunar Eclipse Gallery


Midnight Solar Eclipse Gallery
[NASA: A Rare Eclipse of the Midnight Sun]

  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 June 21, 2011 there were 1224 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 LT17
Jun 15
4.6 LD
--
180 m
2004 LO2
Jun 15
9.9 LD
--
48 m
2011 GA55
Jul 6
64.1 LD
--
1.0 km
2011 EZ78
Jul 10
37.3 LD
--
1.6 km
2003 YS117
Jul 14
73.9 LD
--
1.0 km
2007 DD
Jul 23
9.3 LD
--
31 m
2009 AV
Aug 22
49.7 LD
--
1.1 km
2003 QC10
Sep 18
50 LD
--
1.2 km
2004 SV55
Sep 19
67.5 LD
--
1.2 km
2007 TD
Sep 23
3.8 LD
--
58 m
2002 AG29
Oct 9
77.1 LD
--
1.0 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
Science Central
 
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  more links...
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