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Solar wind
speed: 412.1 km/sec
density: 4.7 protons/cm3
explanation | more data
Updated: Today at 2350 UT
X-ray Solar Flares
6-hr max: C6
2115 UT Sep17
24-hr: M1
0940 UT Sep17
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 17 Sep 15
Sunspot AR2415 has a 'beta-gamma' magnetic field that harbors energy for M-class solar flares. Credit: SDO/HMI

Sunspot number: 67
What is the sunspot number?
Updated 17 Sep 2015

Spotless Days
Current Stretch: 0 days
2015 total: 0 days (0%)

2014 total: 1 day (<1%)
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%)

Updated 17 Sep 2015


The Radio Sun
10.7 cm flux: 109 sfu
explanation | more data
Updated 17 Sep 2015

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/Ovation
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 4
unsettled
explanation | more data
Interplanetary Mag. Field
Btotal: 5.7 nT
Bz: 0.3 nT north
explanation | more data
Updated: Today at 2350 UT
Coronal Holes: 16 Sep 15

Solar wind flowing from this broad northern coronal hole should reach Earth on Sept. 16-18. Credit: SDO/AIA.
Noctilucent Clouds The northern season for NLCs is finished. According to NASA's AIM spacecraft, the last clouds were observed over Greenland on Aug. 27th. Now the waiting begins for the southern season expected to begin in November.
Switch view: Europe, USA, Asia, Polar
Updated at: 09-01-2015 09:00:00
SPACE WEATHER
NOAA Forecasts
Updated at: 2015 Sep 17 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
25 %
25 %
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: 2015 Sep 17 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
25 %
MINOR
05 %
10 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
15 %
MINOR
25 %
30 %
SEVERE
25 %
35 %
 
Thursday, Sep. 17, 2015
What's up in space
 

Learn to photograph Northern Lights like a pro. Sign up for Peter Rosen's Aurora Photo Courses in Abisko National Park, winner of the TripAdvisor Certificate of Excellence Award 2015.

 
Lapland tours

INCREASING CHANCE OF FLARES: Sunspot AR2415 is increasingly active on Sept.17th and appears poised to produce a moderately strong M-class solar flare. Any eruptions today would be geoeffective because the sunspot is facing Earth. Solar flare alerts: text or voice

SOLARSAURUS: An enormous cloud of plasma is rotating into view over the sun's eastern limb. Astrophotographer Alan Friedman calls it "solarsaurus." He took this picture from his backyard in Buffalo, NY, on Sept. 16th:

The dino-shaped cloud is held above the surface of the sun by solar magnetic fields. Stretching more than 600,000 km from end to end, it is truly enormous, by far the largest structure on the sun today.

Astronomers call this kind of magnetized cloud a "hedgerow prominence." NASA and Japanese space telescopes have taken high resolution images of of similar prominences and seen some amazing things such as (1) tadpole-shaped plumes that float up from the base of the prominence; (2) narrow streams of plasma that descend from the top like waterfalls; and (3) swirls and vortices that resemble van Gogh's Starry Night.

Got a solar telescope? Take a look!

Realtime Space Weather Photo Gallery

DRONE-BOW: To see a rainbow, all you need are sunlight and falling rain. Correction: that's all you need to see half a rainbow. Typical rainbows are at least 50% hidden below the horizon.To see a complete rainbow, you also need a drone. Witness this picture taken by a drone over the Netherlands on Sept. 16th:

The drone's master is photographer Martijn Harleman. He explains what happened: "Just after a short rain shower, the sun peeked through. With still some drops still falling I quickly launched my drone. As the drone ascended, the full circle showed up. I stitched together 17 pictures to capture (almost) the whole phenomenon."

The drone view illustrates another common yet frequently overlooked aspect of rainbows. They are double. The interior or "primary rainbow" is caused by one reflection inside raindrops. The exterior or "secondary rainbow" is caused by two reflections. Turns out, you can learn a lot about rainbows by flying a drone.

Realtime Space Weather Photo Gallery

SUNDIVING COMET DESTROYED: The solar system now has one less comet. Earlier today, a sundiving comet discovered on Sept. 15th by Worachate Boonplod, a science writer from Thailand, passed too close to the sun and apparently evaporated. A coronagraph onboard the Solar and Heliospheric Observatory (SOHO) recorded the death plunge:

One comet went in, no comets came out. Fierce heat from the sun likely evaporated the comet's fragile ices, transforming it into a diaphanous cloud of gas and dust.

Sundiving comets are more common than you might think. SOHO has found more than 3000 of them. Most are members of the Kreutz family. Kreutz sungrazers are fragments from the breakup of a single giant comet many centuries ago. They get their name from 19th century German astronomer Heinrich Kreutz, who studied them in detail. Kreutz fragments pass by the sun and disintegrate almost every day. Most, measuring less than a few meters across, are too small to see, but occasionally a bigger fragment like this one attracts attention.


Realtime Aurora Photo Gallery


Realtime Sprite Photo Gallery


Realtime NLC Photo Gallery

  All Sky Fireball Network

Every night, a network of NASA all-sky cameras scans the skies above the United States for meteoritic fireballs. Automated software maintained by NASA's Meteoroid Environment Office calculates their orbits, velocity, penetration depth in Earth's atmosphere and many other characteristics. Daily results are presented here on Spaceweather.com.

On Sep. 17, 2015, the network reported 28 fireballs.
(27 sporadics, 1 September epsilon Perseid)

In this diagram of the inner solar system, all of the fireball orbits intersect at a single point--Earth. The orbits are color-coded by velocity, from slow (red) to fast (blue). [Larger image] [movies]

  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, 2015 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Size
2015 RW35
Sep 13
2.1 LD
6 m
2014 KS76
Sep 14
8.7 LD
22 m
2015 SA
Sep 15
2.9 LD
39 m
2004 TR12
Sep 15
58.8 LD
1.0 km
2015 RU36
Sep 26
14.7 LD
33 m
2015 RF36
Sep 30
14.6 LD
101 m
2000 SM10
Oct 2
11.7 LD
65 m
2000 FL10
Oct 10
65.7 LD
1.9 km
2011 QD48
Oct 17
67.5 LD
1.0 km
2014 UR
Oct 18
3.8 LD
21 m
2011 SE97
Oct 18
11.9 LD
50 m
2001 UY4
Oct 21
58.2 LD
1.0 km
2005 UL5
Nov 20
5.9 LD
390 m
2003 EB50
Nov 29
48.8 LD
2.2 km
2007 BG29
Dec 1
54.1 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
Columbia Northern High School
  Web-based high school science course with free enrollment
Aspendell California
   
  more links...
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