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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 306.0 km/sec
density: 2.0 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: C3
2037 UT Jul28
24-hr: C5
1212 UT Jul28
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 28 Jul 11
NOAA forecasters estimate a 40% chance of M-class flares from one of the three emerging sunspot groups during the next 24 hours. . Credit: SDO/HMI
Sunspot number: 54
What is the sunspot number?
Updated 27 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 27 Jul 2011


The Radio Sun
10.7 cm flux: 99 sfu
explanation | more data
Updated 27 Jul 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 3.5 nT
Bz: 3.2 nT north
explanation | more data
Updated: Today at 2344 UT
Coronal Holes: 28 Jul 11
A solar wind stream flowing from this coronal hole could reach Earth on July 30th or 31st. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Jul 28 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
40 %
40 %
CLASS X
05 %
05 %
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 28 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
 
Thursday, Jul. 28, 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

DISINTEGRATING COMET MOVIE: Note to comets: Stay away from the sun. On July 5th, an icy comet dove into the sun and disintegrated. New footage just released by NASA shows the final stages of the death plunge.

BIG SUNSPOTS: NOAA forecasters estimate a 40% chance of M-class solar flares today. The source would be one of three big sunspots emerging along the sun's northeastern limb. Click on the image to view a 3-day movie from NASA's Solar Dynamics Observatory:

Among the three, the leading sunspot AR1260 is most active. It has produced more than a dozen C-class flares in the past 24 hours, more than doubling the total for the entire month of July so far. New sunspot AR1262, however, could eventually cause more trouble. Magnetograms of the active region reveal a delta-class magnetic field that harbors energy for powerful X-class eruptions. Readers with solar telescopes are encouraged to monitor developments.

more images: from Achim Marian Lucian of Targu Jiu, Gorj, Romania; from Peter Desypris of Island of Syros, Greece; from Gianfranco Meregalli of Milano Italy; from Ron Cottrell of Kitt Peak National Observatory; from John Minnerath of Crowheart, Wyoming; from Cai-Uso Wohler of Bispingen, Germany

NOCTILUCENT CLOUDS: "The morning of July 26th was electric blue!" says Heiko Ulbricht of Freital, Saxony, Germany. "I woke up at 3 clock, looked out my bedroom window to the north and saw a stunning display of noctilucent clouds." Moments later, he dashed outside with a camera to record the view:

July has been an odd time for noctilucent clouds (NLCs). The month began with an extravagant display that stretched as far south as Colorado and Kansas--odd because NLCs are usually confined to higher latitudes. The event seemed to herald a period of widespread sightings. Observers were disappointed, though, when the clouds quickly retreated to their usual northern habitat. Could this German apparition signal renewed activity? Sky watchers at all latitudes should be alert for electric-blue ripples around sunrise and sunset. Observing tips may be found in the gallery.

more images: from Timo Newton-Syms of Helsinki, Finland

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 28, 2011 there were 1237 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
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.
STEREO
  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
Heliophysics
  the underlying science of space weather
Science Central
 
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