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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 392.1 km/sec
density: 0.7 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: C4
1727 UT Jul31
24-hr: C6
0000 UT Jul31
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 31 Jul 12
Sunspot AR1532 is decaying and poses a declining threat for M-class solar flares. Credit: SDO/HMI
Sunspot number: 106
What is the sunspot number?
Updated 31 Jul 2012

Spotless Days
Current Stretch: 0 days
2012 total: 0 days (0%)
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 821 days
Typical Solar Min: 486 days

Updated 31 Jul 2012


The Radio Sun
10.7 cm flux: 136 sfu
explanation | more data
Updated 31 Jul 2012

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: 3.2 nT
Bz: 2.3 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 31 Jul 12
A medium-speed solar wind stream flowing from this coronal hole is buffeting Earth's magnetic field. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2012 Jul 31 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
35 %
35 %
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: 2012 Jul 31 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
20 %
MINOR
01 %
10 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
15 %
25 %
SEVERE
05 %
30 %
 
Tuesday, Jul. 31, 2012
What's up in space
 

Listen to radar echoes from satellites and meteors, live on listener-supported Space Weather Radio.

 
Spaceweather Radio is on the air

STRANGE BUT TRUE: CURIOSITY'S SKY CRANE: How do you deposit a massive SUV-sized nuclear-powered rover to the surface of an alien planet without making an SUV-sized crater? NASA's solution for Curiosity will be attempted for the first time on August 5/6 when they gently lower the rover to the red sands of Mars using a Sky Crane. [full story] [video: Mars Landing Sky Show]

EARLY PERSEID METEORS: Earth is entering a broad stream of debris from Comet Swift-Tuttle, source of the annual Perseid meteor shower. Meteoroids in the outskirts of the stream are now hitting Earth's atmosphere, producing as many as 10-15 meteors per hour according to worldwide counts from the International Meteor Organization. NASA's network of all-sky meteor cameras captured 17 Perseid fireballs on the nights of July 28th through 30th. Here are their orbits:

The position of Earth is denoted by the red starburst; all of the meteoroid orbits intersect at that point. The purple line traces the orbit of the parent Comet Swift-Tuttle. Fortunately, the comet itself does not intersect Earth.

In the days ahead, Earth will plunge deeper into the meteoroid stream, and meteor rates will increase accordingly. Forecasters expect the shower to peak on August 12-13 with as many as 100+ meteors per hour visible from dark-sky sites. Monitor the realtime meteor gallery for sightings.

Realtime Meteor Photo Gallery

SUBSIDING MAELSTROM: Sunspot AR1532 has been active, producing an M-class flare almost every day since it appeared last Friday. On July 28th, amateur astronomer Viljo Nylund of Finland photographed the maelstrom of hot plasma surrounding the sunspot's dark core:

Nylund used an H-alpha telescope tuned to the red glow of solar hydrogen. "The area around AR1532 looked very active and interesting, so I decided to try my luck. I made an inverted version of the image to highlight the 3D feel."

The maelstrom might be subsiding. A full day has gone by without a significant flare, and the active region's underlying spotted area is decreasing. NOAA forecasters estimate the chances of an M-class flare today to be 35%. Solar flare alerts: text, voice.

Realtime Space Weather Photo Gallery


Realtime Noctilucent Cloud Photo Gallery
[previous years: 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2011]

  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 31, 2012 there were 1324 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2002 AM31
Jul 22
13.7 LD
--
1.0 km
2012 OQ
Jul 24
7.7 LD
--
190 m
2012 OU1
Jul 25
8.5 LD
--
54 m
37655 Illapa
Aug 12
37 LD
--
1.2 km
2000 ET70
Aug 21
58.5 LD
--
1.1 km
1998 TU3
Aug 25
49.2 LD
--
4.9 km
2009 AV
Aug 26
62.8 LD
--
1.1 km
1998 UO1
Oct 4
60.1 LD
--
2.1 km
2005 GQ21
Oct 12
77 LD
--
1.0 km
1998 ST49
Oct 18
28.7 LD
--
1.3 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
Trade Show Displays
   
  more links...
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