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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 419.2 km/sec
density: 1.1 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: C4
2218 UT Jul18
24-hr: C4
2218 UT Jul18
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 18 Jul 12
Sunspot 1520 poses a threat for M-class solar flares. As the sunspot turns away from Earth, however, the chances of a geoeffective eruption are decreasing. Credit: SDO/HMI
Sunspot number: 87
What is the sunspot number?
Updated 17 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 17 Jul 2012


The Radio Sun
10.7 cm flux: 138 sfu
explanation | more data
Updated 17 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: 4.7 nT
Bz: 2.3 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 18 Jul 12
A solar wind stream flowing from this coronal hole should reach Earth on or about July 21st. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2012 Jul 18 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
30 %
10 %
CLASS X
10 %
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 18 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
15 %
15 %
MINOR
10 %
10 %
SEVERE
05 %
05 %
 
Wednesday, Jul. 18, 2012
What's up in space
 

Hang the Transit of Venus on your wall! Hubble-quality images from NASA's Solar Dynamics Observatory are now available as metallic posters in the Space Weather Store.

 
Venus Transit metal posters

MARTIAN MARATHON: More than 8 years after landing on the Red Planet, Mars rover Opportunity is still running. Indeed, mission planners say the tireless robot is poised to complete a full marathon--the first ever long-distance race on an alien planet. [full story] [video]

SLOW EXPLOSION: Sunspot complex AR1520-1521 erupted on July 17th, producing an M1-class flare that unfolded slowly over a period of hours. Slow explosions often produce CMEs, and this one was no exception. Click on the image to view a movie of the bright, massive cloud recorded by the Solar and Heliospheric Observatory:

According to a forecast track prepared by analysts at the Goddard Space Weather Lab, the CME will hit Venus on July 19th and could deliver a glancing blow to Earth on July 20th. The impact could re-energize but not rival the spectacular light show of July 14th through 16th. Aurora alerts: text, voice.

Realtime Space Weather Photo Gallery

NOCTILUCENT CLOUDS IN MOTION: "Last night some nice noctilucent clouds appeared over Stockholm," reports Swedish photographer Peter Rosen. "Watching NLCs this summer has made me take an interest in their intricate movements--so I decided to create some close-up timelapse movies using a telephoto lens." Click on the image to set the scene in motion:

"What looked like a serene view from a distance behaves more like a stormy sea with wave after wave rolling in," he observes.

When NLCs first appeared in the 19th century, the mysterious clouds were confined to the Arctic, most often seen in the same places as Northern Lights. In recent years, however, their "habitat" has been expanding, rippling as far south as Colorado, Virginia, Kansas, and Utah. There is growing evidence that the expansion is a sign of climate change, although this remains controversial.

Whatever the reason for the expansion, it means the "stormy sea" could be coming to a sky near you. Observing tips: Look west 30 to 60 minutes after sunset when the sun has dipped 6o to 16o below the horizon. If you see electric-blue waves spreading across the sky, you've probably spotted a noctilucent cloud.

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 18, 2012 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2003 KU2
Jul 15
40.2 LD
--
1.3 km
2004 EW9
Jul 16
46.8 LD
--
2.1 km
2002 AM31
Jul 22
13.7 LD
--
1.0 km
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
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
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  more links...
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