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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 363.3 km/sec
density: 10.3 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B8
2005 UT Jul17
24-hr: B8
2005 UT Jul17
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 17 Jul 11
A new sunspot is emerging at the circled location. Credit: SDO/HMI
Sunspot number: 75
What is the sunspot number?
Updated 16 Jul 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 16 Jul 2011

The Radio Sun
10.7 cm flux: 94 sfu
explanation | more data
Updated 16 Jul 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 6.2 nT
Bz: 2.4 nT north
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 17 Jul 11
Solar wind flowing from the indicated coronal hole should reach Earth around July 19-20. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Jul 17 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 Jul 17 2200 UTC
0-24 hr
24-48 hr
10 %
20 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
25 %
01 %
01 %
01 %
01 %
Sunday, Jul. 17, 2011
What's up in space

Are we alone? Your iPhone has the answer. Download the all-new Drake Equation app to calculate the population of the Milky Way.

DrakeEQ for iPhone and iPad

DAWN ORBITS VESTA: NASA's ion-propelled Dawn spacecraft has entered orbit around giant asteroid Vesta. Because of uncertainties in Vesta's mass, mission scientists aren't sure exactly when Vesta's gravity captured Dawn. Best guess: sometime on July 16th. Stay tuned for updates and photos in the days ahead as Dawn begins a year-long study of the asteroid from close range.

Would you like to own a piece of Vesta? It's possible. Authentic Vesta meteorites are now available in the Space Weather Store.

AURORAS UNDERFOOT: Earth orbit is a great place to watch geomagnetic storms. On July 14th, astronauts onboard the International Space Station (ISS) witnessed a broad curtain of green auroras over the southern hemisphere. This is what aurora australis looks like from space:

The picture was taken by one of the crew of space shuttle Atlantis, now docked to the ISS for the last resupply mission of NASA's 30-year shuttle program. In addition to Southern Lights, the picture also frames Atlantis's port side wing and a segment of the boom sensor system attached to the shuttle's robotic arm. See also the panoramic shot.

The display was caused by a solar wind stream which hit Earth's magnetic field on July 12th. Note to astronauts: Another solar wind stream is heading for Earth, due to arrive on July 19th-20th. The crew of Atlantis should remain alert for auroras.

BONUS: The same display was seen from Earth's surface. Robert Schwarz sends two snapshots from the Amundsen-Scott South Pole Station in Antarctica. "Absolutely amazing," says Schwarz. "These were some of the best auroras I have ever seen."

SOLAR TRANSITS: To the dismay of sky watchers in Europe and North America, space shuttle Atlantis has not appeared very often in the night sky during the ongoing final mission of NASA's shuttle program. The apparitions have been taking place instead during broad daylight. French astrophotographer Thierry Legault sends this picture of Atlantis and the ISS passing directly in front of the sun on July 15th:

"We enjoyed a rare day with clear skies," says Legault. "Good seeing allowed me to capture many details of the docked spacecraft." A labeled close-up shows the crisp outlines of Atlantis, a Progress cargo ship, the space station's wide solar panels, and many of the station's research modules and crew quarters--all silhouetted by solar fire. Daytime apparitions aren't so bad, after all.

The shuttle is scheduled to return to Earth on Thursday, July 21st, never to fly again. Farewell, Atlantis, and thanks for all the transits!

more images: from Alan Friedman and Donna Massimo on the shore of Lake Ontario in Lyndonville, NY; from Catalin Paduraru of Curcani, Romania; from Leonardo Julio of Buenos Aires, Argentina; from Ehsan Rostamizadeh of Kerman,Iran

2011 Noctilucent Cloud Gallery
[previous years: 2003, 2004, 2005, 2006, 2007, 2008, 2009]

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

  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 July 17, 2011 there were 1237 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
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
1.1 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
2011 FZ2
Nov 7
75.9 LD
1.6 km
2005 YU55
Nov 8
0.8 LD
175 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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