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Solar wind
speed: 479.7 km/sec
density: 1.8 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: C3
1733 UT Jul12
24-hr: C3
1733 UT Jul12
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 12 July 13
Decaying sunspot complex AR1785-87 poses a slim threat for M-class solar flares. Credit: SDO/HMI
Sunspot number: 85
What is the sunspot number?
Updated 12 Jul 2013

Spotless Days
Current Stretch: 0 days
2013 total: 0 days (0%)
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

Update
12 Jul 2013

The Radio Sun
10.7 cm flux: 113 sfu
explanation | more data
Updated 12 Jul 2013

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 3
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 11.3 nT
Bz: 5.8 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 12 Jul 13
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.

Spaceweather.com is now posting daily satellite images of noctilucent clouds (NLCs), which hover over Earth's poles at the edge of space. The data come from NASA's AIM spacecraft. The north polar "daisy" pictured below is a composite of near-realtime images from AIM assembled by researchers at the University of Colorado's Laboratory for Atmospheric and Space Physics (LASP).
Noctilucent Clouds
Switch view: Europe, USA, Asia, Polar
Updated at: 07-12-2013 10:55:03
SPACE WEATHER
NOAA Forecasts
Updated at: 2013 Jul 12 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
10 %
10 %
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: 2013 Jul 12 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
35 %
35 %
MINOR
15 %
30 %
SEVERE
01 %
05 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
10 %
MINOR
30 %
25 %
SEVERE
40 %
65 %
 
Friday, Jul. 12, 2013
What's up in space
 

When is the best time to see auroras? Where is the best place to go? And how do you photograph them? These questions and more are answered in a new book, Northern Lights - a Guide, by Pal Brekke & Fredrik Broms.

 
Northern Lights - a Guide

CHANCE OF STORMS: NOAA forecasters estimate a 40% chance of polar geomagnetic storms on July 13th when a CME is expected to hit Earth's magnetic field. Computer models of the incoming CME anticipate a sharp increase in solar wind plasma density around the time of the crossing. This could spark bright auroras at high latitudes. Aurora alerts: text, voice.

WEAK IMPACT, BRIGHT LIGHTS: A weak CME impact on July 9th gave sky watchers more than they bargained for. Although the blow was feeble, both ends of the Earth lit up with auroras that persisted for nearly two days. Minoru Yoneto photographed the display from Queenstown, New Zealand:

"I did not expect to see big, bright Southern Lights from such a weak CME impact," says Yoneto. "Yet they were definitely present on July 10th." Sky watchers in Canada and northern-tier US states from Michigan to Washington saw similar displays right up until sunrise on July 11th.

The CME was effective in sparking high-latitude auroras because its wake contained a south-pointing magnetic field--a.k.a. "negative Bz". This opened a crack in Earth's magnetosphere, allowing solar wind to pour in and fuel the Northern and Southern Lights.

The moral to this story: Even weak CMEs can trigger bright auroras if the CME is dragging behind it a south-pointing magnetic field. The next CME is due on JUly 13th. Stay tuned. Aurora alerts: text, voice.

Realtime Aurora Photo Gallery

GREEN SKIES OVER TEXAS: Not all colorful lights in the sky are the aurora borealis. Astrophotographer Kenneth Edwards discovered this for himself on July 4th when he was taking a long exposure of the Milky Way over Big Bend National Park, Texas:

"For the long 4th of July weekend I went with my daughter to Big Bend National Park to try some time lapse photography of the Milky Way," says Edwards. "After getting back home, I was creating a time lapse video when I noticed the green colors. They were not visible to the naked eye but it sure was clear in the pictures and videos."

The green light is called "airglow." Airglow is a luminous bubble that surounds our entire planet, fringing the top of the atmosphere with aurora-like color. Although airglow resembles the aurora borealis, its underlying physics is different. Airglow is caused by an assortment of chemical reactions in the upper atmosphere driven mainly by solar ultraviolet radiation; auroras, on the other hand, are ignited by gusts of solar wind.

Green airglow is best photographed from extremely dark sites on nights when the Moon is new or below the horizon. It often shows up in long exposures of the Milky Way: more airglow.

Realtime Space Weather Photo Gallery


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


Realtime Comet Photo 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 12, 2013 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Size
2013 NH4
Jul 6
4.3 LD
30 m
2013 NJ4
Jul 7
3.9 LD
14 m
2001 PJ9
Jul 17
29.2 LD
1.1 km
2006 BL8
Jul 26
9.3 LD
48 m
2003 DZ15
Jul 29
7.6 LD
153 m
2005 WK4
Aug 9
8.1 LD
420 m
1999 CF9
Aug 23
24.7 LD
1.1 km
2002 JR9
Aug 31
63.5 LD
1.4 km
1992 SL
Sep 23
70 LD
1.1 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
Space Weather Alerts
   
  more links...
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