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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 409.0 km/sec
density: 4.2 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: B4
2114 UT Jul18
24-hr: C1
1029 UT Jul18
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 18 Jul 11
New sunspot 1257 poses a threat for C-class solar flares. Credit: SDO/HMI
Sunspot number: 101
What is the sunspot number?
Updated 17 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 17 Jul 2011

The Radio Sun
10.7 cm flux: 104 sfu
explanation | more data
Updated 17 Jul 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: 8.3 nT
Bz: 0.0 nT
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 18 Jul 11
Solar wind flowing from the indicated coronal hole could reach Earth as early as July 19-20. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Jul 18 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 18 2200 UTC
0-24 hr
24-48 hr
25 %
30 %
01 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
30 %
35 %
01 %
10 %
01 %
01 %
Monday, Jul. 18, 2011
What's up in space

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

Satellite flybys

AURORA WATCH: High-latitude sky watchers should be alert for auroras. Earth is entering a solar wind stream that could trigger minor geomagnetic storms on July 19th and 20th. Observers in the southern hemisphere with winter-dark midnight skies are favored.

FIRST CLOSE-UP OF VESTA: Mission scientists have confirmed that Dawn is indeed in orbit around Vesta. The giant asteroid's gravity captured the spaceship during the early hours of July 16th. In return, Dawn's cameras captured the first close-up image of Vesta, just released by NASA:

The image taken for navigation purposes shows Vesta in greater detail than ever before. For comparison, take a look at previous best images of Vesta taken by the Hubble telescope in 1996.

Vesta is 530 kilometers in diameter and the second most massive object in the asteroid belt. Ground- and space-based telescopes have been photographing the ancient asteroid for two centuries, but they have not been able to see much detail on its surface. Dawn will change all that as it orbits Vesta for a full year, taking increasingly close pictures of "arguably the oldest extant primordial surface in the solar system," says Dawn principal investigator Christopher Russell of UCLA.

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

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 transit 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; from Jay Lawson of Fallon, Nevada; from John Stetson of Kennebunk, Maine; from Martin Gembec of Mikulasovice, Czech Republic; from Blake Estes of Santa Barbara, California; from Jim Haklar of Edison, New Jersey

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 18, 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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