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Solar wind
speed: 535.6 km/sec
density: 1.4 protons/cm3
explanation | more data
Updated: Today at 2351 UT
X-ray Solar Flares
6-hr max: M2
1803 UT Sep20
24-hr: M2
1803 UT Sep20
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 20 Sep 15
Sunspot AR2415 has a 'beta-gamma' magnetic field that harbors energy for M-class solar flares. Credit: SDO/HMI

Sunspot number: 61
What is the sunspot number?
Updated 20 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 20 Sep 2015


The Radio Sun
10.7 cm flux: 106 sfu
explanation | more data
Updated 20 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= 7
strong
explanation | more data
Interplanetary Mag. Field
Btotal: 6.5 nT
Bz: 0.6 nT north
explanation | more data
Updated: Today at 2351 UT
Coronal Holes: 20 Sep 15

There are no large coronal holes on the Earthside of the sun. 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 20 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
40 %
40 %
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 20 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
40 %
25 %
MINOR
20 %
10 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
15 %
MINOR
30 %
30 %
SEVERE
50 %
35 %
 
Sunday, Sep. 20, 2015
What's up in space
 

On Sept. 27th, the Harvest Moon will pass through the shadow of Earth, turning the lunar disk a lovely shade of celestial red. Catch it live on the Internet, courtesy of the Coca-Cola Space Science Center in Columbus, Georgia.

 
Eclipse Webcast

CME IMPACT SPARKS STRONG GEOMAGNETIC STORM: Arriving a full day earlier than expected, a CME hit Earth's magnetic field on Sept. 20th at approximately 0600 UT. The impact sparked a strong G3-class geomagnetic storm and bright auroras over high-latitude regions of North America. "It was a great light show," reports Todd Salat, who sends this picture from his backyard garden in Anchorage, Alaska:

"At first, I was planning to go watch the auroras from the nearby mountains, but decided to stay home because of this late but great six-foot tall sunflower!"says Salat. "I figured it was a unique opportunity to shoot the auroras over Helianthus."

The storm is subsiding now, but it could flare up again as Earth passes through the wake of the CME. NOAA forecasters estimate a 50% chance of more geomagnetic storming on Sept. 20-21. Aurora alerts: text or voice

Realtime Aurora Photo Gallery

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."

Realtime Space Weather 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. 20, 2015, the network reported 11 fireballs.
(11 sporadics)

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 20, 2015 there were 1611 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Size
2015 SA
Sep 15
2.9 LD
38 m
2004 TR12
Sep 15
58.8 LD
1.0 km
2015 SH
Sep 15
2.5 LD
11 m
2015 SB
Sep 18
10 LD
20 m
2015 SM
Sep 18
4 LD
9 m
2015 SM
Sep 19
4 LD
9 m
2015 SE
Sep 20
4.2 LD
23 m
2015 SU
Sep 23
14.8 LD
36 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
2015 SR
Oct 3
14.7 LD
56 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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