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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 395.6 km/sec
density: 6.5 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B2
2231 UT Jun20
24-hr: B4
0607 UT Jun20
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 20 Jun 11
All three of these sunspots are quiet and pose little threat for strong flares. Credit: SDO/HMI
Sunspot number: 47
What is the sunspot number?
Updated 19 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 19 Jun 2011

The Radio Sun
10.7 cm flux: 99 sfu
explanation | more data
Updated 19 Jun 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 3
explanation | more data
Interplanetary Mag. Field
Btotal: 6.9 nT
Bz: 1.6 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 20 Jun 11
A solar wind stream flowing from the indicated coronal hole could reach Earth on June 23rd. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Jun 20 2200 UTC
0-24 hr
24-48 hr
10 %
10 %
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 20 2200 UTC
0-24 hr
24-48 hr
20 %
10 %
05 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
25 %
15 %
10 %
01 %
01 %
01 %
Monday, Jun. 20, 2011
What's up in space

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

Satellite flybys

HANG AN EXPLOSION ON YOUR WALL: The solar super-explosion of June 7, 2011, has been turned into a unique metallic wall hanging now available from the Space Weather Store. Take a look.

SPACE STATION FLYBY: On June 12th through 17th, the ESA's Kepler robotic supply ship used its engines to boost the altitude of the International Space Station by a whopping 35 km, from 345 km to 380 km above Earth. Despite the record-setting increase in distance, the behemoth ISS was visible in detail last night when it orbited over Europe. Germany astronomer Dirk Ewers recorded the flyby through his 5-inch refracting telescope:

"I worried that the 10% increase in altitude would diminish the visibility of fine details," he says. "I needn't have worried. The space station looked crisp and clear as it sparkled in the full sunlight of the summer solstice."

Even the relatively small Kepler is visible in the video docked to one end of the space station's backbone. Not for long, though. Kepler is scheduled to undock on June 20th in preparation for a suicide plunge into the atmosphere over the Pacific Ocean on June 21st. Check the Kepler home page for updates.

ISS flyby predictions: Simple Satellite Tracker, Simple Flybys smartphone app

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

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

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 20, 2011 there were 1224 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
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.
  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
Conquest Graphics
  for out-of-this-world printing and graphics
Trade Show Displays
  more links...
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