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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 380.5 km/sec
density: 0.4 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B3
1910 UT Jun28
24-hr: B9
1321 UT Jun28
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 28 Jun 11
New sunspots are emerging at the circled locations. They are small and pose little threat for strong flares. Credit: SDO/HMI
Sunspot number: 30
What is the sunspot number?
Updated 27 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 27 Jun 2011

The Radio Sun
10.7 cm flux: 89 sfu
explanation | more data
Updated 27 Jun 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 5.1 nT
Bz: 3.5 nT north
explanation | more data
Updated: Today at 2344 UT
Coronal Holes: 28 Jun 11
A solar wind stream flowing from the indicated coronal hole should reach Earth on ~July 2nd.. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Jun 28 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 Jun 28 2200 UTC
0-24 hr
24-48 hr
10 %
10 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
10 %
10 %
01 %
01 %
01 %
01 %
Tuesday, Jun. 28, 2011
What's up in space

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

Satellite flybys

QUIET SUN: June is going to end on a quiet note. Solar activity is very low with only a few small scattered sunspots posing no threat for strong flares.

ASTEROID FLYBY: Asteroid 2011 MD flew past Earth on Monday, June 27th. At closest approach the ~10-meter space rock was only 12,000 kilometers (7,500 miles) above the planet's surface. NASA analysts said there was no chance it would strike Earth, and indeed it didn't.

Astronomers around the world monitored the flyby. Using a remotely-controled telescope in Cerro Tololo, Chile, Joe Pollock of Appalachian State University obtained this light curve:

"The brightness variations are due to the asteroid's spin," explains Pollock. "It appears to be rotating with a 23.3 or 11.6 minute period."

UPDATE: A dramatic video recorded by Andre Paquette of Ottawa, Canada, shows the brightness of the asteroid oscillating as it races among the stars. "My light curve is a good match to Cerro Tololo's," says Paquette.

more flyby movies and images: from Jure Skvarc of the Črni Vrh Observatory in Slovenia; from Marco Langbroek of Sierra Stars Obs., California; from Efrain Morales Rivera of Aguadilla, Puerto Rico; from Nick Howes of Siding Spring Australia; from Rafael Ferrando of the Observatory Pla d'Arguines in Segorbe, Spain; from Libor Vyskocil of the Observatory Upice in the Czech Republic; from Nick James of Chelmsford, UK; from Rolando Ligustri of Talmassons Observatory, Italy;

ELECTRIC BLUE STORKS: Electric-blue noctilucent clouds are rippling over Europe this week. In Poland, that means sky watchers should be alert for the silhouettes of storks:

Marek Nikodem of Szubin, Poland, caught this specimen backlit by night-shining clouds on June 26th. "Each year in late spring-early summer, thousands of storks (Ciconia ciconia) arrive in Poland for nesting," he says. "Their arrival coincides with the summer onset of noctilucent clouds. Whenever young storks are born in the heavens, we can admire the NLCs!"

Noctilucent clouds form at the very top of Earth's atmosphere, at the edge of space itself where meteoroids can seed the formation of tiny ice crystals. When summer sunlight strikes these crystals--voila!--the sky glows electric blue. High-latitude observers should look for these strange clouds just after sunset or before sunrise; observing tips may be found in the 2009 NLC gallery.

more images: from Ivo Dinsbergs of Riga, Latvia; from John Houghton of Newtown Linford, Leicestershire; from Aurimas Dirse of Vilnius, Lithuania; from Barbara Grudzinska of Warsaw, Poland; from Richard Fleet of Pewsey Vale, Wiltshire, England;

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

June 15th Lunar Eclipse Gallery

  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 28, 2011 there were 1237 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 MD
Jun 27
0.05 LD
10 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
2003 BK47
Jul 26
77.6 LD
1.0 km
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
2000 OJ8
Oct 13
49.8 LD
2.5 km
2009 TM8
Oct 17
1.1 LD
8 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.
  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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