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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 363.7 km/sec
density: 4.9 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B6
1705 UT Jul16
24-hr: B6
1705 UT Jul16
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 16 Jul 11
The sun is peppered with spots, but none of them poses a threat for strong flares. Credit: SDO/HMI
Sunspot number: 90
What is the sunspot number?
Updated 15 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 15 Jul 2011

The Radio Sun
10.7 cm flux: 94 sfu
explanation | more data
Updated 15 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: 4.6 nT
Bz: 1 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 16 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 16 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 Jul 16 2200 UTC
0-24 hr
24-48 hr
05 %
10 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
10 %
15 %
01 %
01 %
01 %
01 %
Saturday, Jul. 16, 2011
What's up in space

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

Satellite flybys

CLOSE ENCOUNTER WITH VESTA: This weekend, NASA's Dawn spacecraft is entering orbit around Vesta for a year-long study of the giant asteroid. Dawn's cameras are expected to reveal a primitive world of desolate beauty from close range. As close as Dawn will be, however, you can be even closer; it's actually possible to hold a piece of Vesta in your hand. 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."

SPOOKY COMMUNICATION: "The skies over the Spanish island of La Palma offer many beauties, but on July 4th I witnessed something unusual: a ghostly green laser beam crossing the Milky Way," reports Jan Hattenbach from the Canary Islands. "I have learned that it was part of an experiment in quantum communication." Scroll past the laser for more information:

"Rupert Ursin of the Institute for Quantum Optics and Quantum Information at the Austrian Academy of Sciences explained to me that the laser was part of an inter-island quantum-cryptography experiment," says Hattenbach. "Physicists send entangled UV-photons from the Roque de los Muchachos observatory (ORM) on La Palma to the European Space Agency's Optical Ground Station 144 km away on the island of Tenerife. The goal is to demonstrate the feasibility of quantum communication over very long distances in space--e.g., to the International Space Station or other satellites.

"While the UV photons are invisible to the human eye, the green laser is not: it is used as a tracking laser or a giant laser pointer. It remained visible even in broad twilight - and made a good show together with the milky way, the morning zodiacal light and Jupiter."

Sending coded information via entangled photons? If the idea disturbs you, you're in good company. Einstein himself ridiculed the notion as "spooky action at a distance." Experiments like this one, however, show that it is possible.

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 16, 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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