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Solar wind
speed: 437.2 km/sec
density: 5.7 protons/cm3
explanation | more data
Updated: Today at 2350 UT
X-ray Solar Flares
6-hr max: B8
2204 UT Sep18
24-hr: C2
0631 UT Sep18
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 18 Sep 15
Sunspot AR2415 has a 'beta-gamma' magnetic field that harbors energy for M-class solar flares. Credit: SDO/HMI

Sunspot number: 72
What is the sunspot number?
Updated 18 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 18 Sep 2015


The Radio Sun
10.7 cm flux: 107 sfu
explanation | more data
Updated 18 Sep 2015

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/Ovation
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 3
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 7.7 nT
Bz: 3.6 nT south
explanation | more data
Updated: Today at 2351 UT
Coronal Holes: 18 Sep 15

Solar wind flowing from the indicated coronal hole is brushing against Earth's magnetic field today. 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 18 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 18 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
30 %
40 %
MINOR
10 %
20 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
10 %
MINOR
30 %
30 %
SEVERE
35 %
50 %
 
Friday, Sep. 18, 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

ACTIVE SUNSPOT: The magnetic field of sunspot AR2415 is strongly sheared with mixed polarities shoved into close, and explosive, proximity. Breaking and reconnection of magnetic field lines in the sunspot's core could produce an M-class solar flare on Sept. 18th. Solar flare alerts: text or voice

INCREDIBLE NEW PHOTOS OF PLUTO: NASA is still downloading images from the Pluto flyby two months ago. Some of the new arrivals, like this one received on Sept. 13th, are causing researchers to question what they thought they knew about the distant dwarf planet:

New Horizons snapped the picture looking back at Pluto about 15 minutes after its closest approach on July 14th. Backlit by the sun, Pluto's rugged, icy mountains tower over a vast frozen plain extending to the horizon. The backlighting highlights more than a dozen layers of haze in Pluto's tenuous but distended atmosphere.

The new pictures provide evidence for a remarkably Earth-like "hydrological" cycle on Pluto – but involving soft and exotic ices, including nitrogen, rather than water ice. There are signs of hazes, evaporation, precipitation, and flowing glaciers similar to the frozen streams on the margins of ice caps on Greenland and Antarctica.

"We did not expect to find hints of a nitrogen-based glacial cycle on Pluto operating in the frigid conditions of the outer solar system," says Alan Howard, a member of the mission's science team from the University of Virginia. "Driven by dim sunlight, this would be directly comparable to the hydrological cycle that feeds ice caps on Earth, where water is evaporated from the oceans, falls as snow, and returns to the seas through glacial flow."

"Pluto is surprisingly Earth-like in this regard," adds Alan Stern, principal investigator of the New Horizons mission, "and no one predicted it."

GIANT PROMINENCE: The biggest thing on the sun today is not a sunspot. While most sunspots are about the size of Earth, this enormous prominence measures dwarfs our planet:

Jett Aguilar took the picture from the Philippines. "Early this morning, the weather cooperated in Quezon City and I was able to get a clear image of the beautiful giant hedgerow prominence at the sun's eastern limb "

A "hedgerow prominence" is a massive cloud of plasma held aloft by solar magnetic fields. NASA and Japanese space telescopes have taken high resolution images 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


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. 18, 2015, the network reported 27 fireballs.
(26 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 18, 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 SB
Sep 18
10 LD
20 m
2015 RU36
Sep 26
14.7 LD
33 m
2015 RF36
Sep 30
14.6 LD
109 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
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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