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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 329.3 km/sec
density: 0.1 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: C2
2154 UT Jul27
24-hr: M1
1607 UT Jul27
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 27 Jul 11
New sunspots 1260 and 1261 pose a growing threat M-class flares. Credit: SDO/HMI
Sunspot number: 30
What is the sunspot number?
Updated 26 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 26 Jul 2011


The Radio Sun
10.7 cm flux: 94 sfu
explanation | more data
Updated 26 Jul 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 3.2 nT
Bz: 2.7 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 27 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 27 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
40 %
40 %
CLASS X
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 27 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 %
 
Wednesday, Jul. 27, 2011
What's up in space
 

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

 
Satellite flybys

SUNDIVING COMET MOVIE: A new video from NASA shows the sundiving comet of July 5th interacting with the sun's atmosphere as it evaporates above the stellar surface. Click here for action.

BIG SUNSPOTS: After more than a week of quiet, solar activity is picking up. NASA's Solar Dynamics Observatory is monitoring two big sunspot groups now emerging over the sun's eastern limb. Click on the image to view a 40-hour movie:

The leading sunspot group, AR1260, is crackling with M- and C-class solar flares among a quartet of Earth-sized cores. Not far behind, sunspot AR1261 is larger and may harbor energy for flares of its own. At the moment, these two sunspot groups are too far off disk-center to affect Earth, but this will change in the days ahead. Readers with solar telescopes are encouraged to monitor developments.

more images: from Pavol Rapavy of Observatory Rimavska Sobota, Slovakia; from Steve Wainwright of Gower S.Wales UK; from John Stetson of Falmouth, Maine; from Rogerio Marcon of Campinas SP Brasil; 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 27, 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
1994 CK1
Nov 16
68.8 LD
--
1.5 km
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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