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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 371.8 km/sec
density: 5.2 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B1
1717 UT Jul06
24-hr: B1
0225 UT Jul06
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 06 Jul 11
Sunspot 1244 has a beta-gamma magnetic field that poses a slim threat for M-class solar flares. Credit: SDO/HMI
Sunspot number: 30
What is the sunspot number?
Updated 05 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 05 Jul 2011

The Radio Sun
10.7 cm flux: 85 sfu
explanation | more data
Updated 05 Jul 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 3
explanation | more data
Interplanetary Mag. Field
Btotal: 5.4 nT
Bz: 0.1 nT north
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 06 Jul 11
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about July 9th. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Jul 06 2200 UTC
0-24 hr
24-48 hr
05 %
05 %
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 06 2200 UTC
0-24 hr
24-48 hr
15 %
35 %
05 %
10 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
40 %
10 %
15 %
01 %
05 %
Wednesday, Jul. 6, 2011
What's up in space

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

Satellite flybys

MINOR STORM WATCH: NOAA forecasters estimate a 10% chance of minor geomagnetic storms on July 7th in response to an incoming CME. High-latitude sky watchers should be alert for auroras.

SUNDIVING COMET: Today, the solar system has one less comet. During the late hours of July 5th, an icy unnamed comet dove into the sun and disintegrated. The comet's last hours were recorded by coronagraphs onboard the the Solar and Heliospheric Observatory (SOHO):

The comet was probably a member of the Kreutz sungrazer family. Named after a 19th century German astronomer who studied them in detail, Kreutz sungrazers are fragments from the breakup of a giant comet at least 2000 years ago. Several of these fragments pass by the sun and disintegrate every day. Most are too small to see but occasionally a big fragment like this one attracts attention.

NASA's STEREO-A and -B spacecraft also recorded the event, and they are beaming their data back to Earth now. In a few days we'll have high-res movies of a comet's death plunge from three points of view: SOHO, STEREO-A and STEREO-B. Stay tuned.

ELECTRIC BLUE CLOUDS: When noctilucent clouds (NLCs) first appeared in the 19th century, they were a high-latitude phenomenon. You had to travel toward the poles to see their electric-blue glow. Not anymore. Just this past weekend, NLCs spilled over the Canadian border into the lower United States as far south as Denver, Colorado. Flying 33,000 feet over the Mile High City on July 2nd, Brian Whittaker snapped this picture from the window of a passenger jet:

Whittaker is a long time observer of NLCs from planes flying much further north. "I was amazed to see them at 39 degrees latitude over the USA," he says.

Another long time observer, University of Colorado atmospheric sciences professor Richard A. Keen was located just underneath the storm clouds in Whittaker's photo. "Rats!" says Keen. "I was watching for NLCs, but all I saw was rain."

During the peak of the display on July 1-2, NLCs were seen in Washington state, Oregon, Montana, North and South Dakota, Minnesota, Colorado and Kansas. Keen notes that the sightings in Colorado (lat 39.8N) and Kansas (lat 38.9N) are among the most southerly sightings ever. "The lowest-latitude sighting I know of was by Craig Coutlee in Ignacio, Colorado on June 22, 1999, the same day as my sighting near Boulder," recalls Keen. "Craig was at 37.1N latitude, just north of New Mexico."

The latest outbreak continues a trend in recent years of NLCs spreading to ever-lower latitudes. Is this a sign of climate change? Some researchers think so. Sky watchers everywhere are encouraged to be alert for electric blue just after sunset or before sunrise; observing tips may be found in the 2011 NLC gallery.

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]

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 July 6, 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
1.1 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
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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