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Solar wind
speed: 371.9 km/sec
density: 1.1 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: B6
2118 UT Sep17
24-hr: B6
2118 UT Sep17
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 17 Sep 13
The Earthside of the sun is very quiet. Solar activity remains low. Credit: SDO/HMI
Sunspot number: 23
What is the sunspot number?
Updated 17 Sep 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
17 Sep 2013

The Radio Sun
10.7 cm flux: 95 sfu
explanation | more data
Updated 17 Sep 2013

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 3
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 6.6 nT
Bz: 1.7 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 17 Sep 13
Solar wind flowing from this coronal hole could reach Earth on Sept. 22-23. 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: 09-02-2013 11:55:02
SPACE WEATHER
NOAA Forecasts
Updated at: 2013 Sep 17 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
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 Sep 17 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
35 %
25 %
MINOR
10 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
25 %
MINOR
35 %
35 %
SEVERE
45 %
25 %
 
Tuesday, Sep. 17, 2013
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

WATCH OUT FOR THE HARVEST MOON: According to folklore, this week's full Moon is the "Harvest Moon." Find out from Science@NASA what makes it special: full story, video.

LONELY SUNSPOT, QUIET SUN: The sunspot number has dropped to its lowest level of the year. Solitary sunspot AR1841 sits all alone at the center of an otherwise blank solar disk. It is quiet and poses no threat for strong flares:

NOAA forecasters estimate a scant 1% chance of M- or X-class solar flares during the next 24-48 hours. If the forecast holds, the sun will continue a spate of deep quiet that has lasted for more than a week, nearly-flatlining the sun's x-ray output.

The quiet spell is a bit strange because 2013 is supposed to be a year of solar maximum, with lots of flares and sunspots. Supporting this view are data from NASA-supported observatories which show that the sun's magnetic field is poised to flip--a long-held sign that Solar Max has arrived. Nevertheless, solar activity is low.

One possible explanation is that Solar Max is double-peaked and we are in the valley between peaks. If so, solar activity could surge again in late 2013-2014. No one can say for sure, though. Researchers have been studying sunspots for more than 400 years, and we still cannot predict the behavior of the solar cycle. Continued quiet or stormy space weather? Both are possible in the weeks and months ahead. Solar flare alerts: text, voice.

Realtime Space Weather Photo Gallery

 

ARCTIC AURORAS TONIGHT? NOAA forecasters estimate a 45% chance of polar geomagnetic storms on Sept. 17th in response to an incoming solar wind stream. When the solar wind arrives, Arctic skies could look like this:

The display was sparked by a similar solar wind stream on Sept. 13th. "As soon as it was dark enough to see the Lady Aurora, we went out to meet her," says photographer June Grønseth of Laukvik, Lofoten, Norway. "As always, it was a huge pleasure to see her dance, and just leave everything else behind."

Sky watchers around the Arctic Circle should be alert for "Lady Aurora" on Sept. 17th as the solar wind approaches. Aurora alerts: text, voice.

Realtime Aurora 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 September 17, 2013 there were 1428 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Size
2013 RS43
Sep 13
2.9 LD
18 m
2013 RT73
Sep 16
8.3 LD
49 m
2013 RM73
Sep 17
2.3 LD
20 m
2013 RF74
Sep 18
5.5 LD
25 m
2013 RZ53
Sep 18
0.6 LD
3 m
2000 DK79
Nov 10
49.1 LD
3.2 km
2011 JY1
Nov 13
8.2 LD
57 m
2001 AV43
Nov 18
3 LD
57 m
2010 CL19
Nov 25
37.6 LD
1.3 km
2013 NJ
Nov 26
2.5 LD
180 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
Space Weather Alerts
   
  more links...
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