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Solar wind
speed: 472.7 km/sec
density: 3.7 protons/cm3
explanation | more data
Updated: Today at 2348 UT
X-ray Solar Flares
6-hr max: C2
1825 UT Apr18
24-hr: C5
1419 UT Apr18
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 18 Apr 15
Sunspot AR2321 has a 'beta-gamma' magnetic field that harbors energy for M-class solar flares. Credit: SDO/HMI

Sunspot number: 93
What is the sunspot number?
Updated 18 Apr 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 Apr 2015


The Radio Sun
10.7 cm flux: 150 sfu
explanation | more data
Updated 18 Apr 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: 3.7 nT
Bz: 1.6 nT south
explanation | more data
Updated: Today at 2348 UT
Coronal Holes: 18 Apr 15

Solar wind flowing from the indicated coronal hole should reach Earth on April 21-22. Credit: SDO/AIA.
Noctilucent Clouds The southern season for NLCs has come to an end. The last clouds were observed by NASA's AIM spacecraft on Feb. 20, 2015. Now attention shifts to the northern hemisphere, where the first clouds of 2015 should appear in mid-May.
Switch view: Ross Ice Shelf, Antarctic Penninsula, East Antarctica, Polar
Updated at: 02-28-2015 02:55:03
SPACE WEATHER
NOAA Forecasts
Updated at: 2015 Apr 18 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
20 %
20 %
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: 2015 Apr 18 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
30 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
30 %
30 %
SEVERE
25 %
35 %
 
Saturday, Apr. 18, 2015
What's up in space
 

Come to Tromsø and share Marianne's passion for rural photography: Chasethelighttours.co.uk invites you to experience "Heaven on Earth" with an aurora, fjord, fishing, whale watching, photography or sightseeing tour.

 
Chase the Light Tours

CHANCE OF EARTH-DIRECTED FLARES: Solar activity is low, but sunspot AR2321 is poised to break the quiet. The sprawling sunspot group is directly facing Earth and has an unstable 'beta-gamma' magnetic field that harbors energy for significant eruptions. NOAA forecasters estimate 40% chance of M-flares and a 10% chance of X-flares during the next 24 hours. Solar flare alerts: text, voice.

SUBSIDING STORM: Earth is exiting a stream of high-speed solar wind that has been blowing around our planet for days. During the period of peak gustiness on April 16-17, a G2-class geomagnetic storm broke out, sparking bright auroras over Scandinavia, Canada, and northern-tier US states. Kameron Barge photographed the colorful lights over Glacier National Park in Montana:

"The sky was calm and clear--perfect conditions for this brilliant display of dancing lights," says Barge. Elsewhere in the USA, auroras were sighted as far south as Wyoming, Washington, Michigan, Minnesota, and Idaho.

The auroras will fade this weekend as Earth moves out of the solar wind stream. However, we should keep in mind that intermittent flare-ups are possible even as the solar wind subsides. NOAA forecasters estimate a 40% chance of renewed geomagnetic storms during the next 24 hours. Aurora alerts: text, voice.

Realtime Aurora Photo Gallery

CORONAL HOLE: NASA's Solar Dynamics Observatory (SDO) is monitoring a hole in the sun's atmosphere--a "coronal hole." It is colored deep-blue in this extreme UV image of the sun taken by SDO on April 17th:

Coronal holes are places where the sun's magnetic field opens up and allows solar wind to escape. In the image, above, the sun's magnetic field is traced by white loops. Arrows show the flow of material out of the hole.

Holes in the sun's atmosphere are not unusual; they appear several times each month. A stream of solar wind flowing from this particular coronal hole will probably reach Earth on April 21-22. This means we could have auroras for Earth Day. Stay tuned. Aurora alerts: text, voice

Realtime Space Weather Photo Gallery


Realtime Eclipse Photo Gallery


Realtime Comet 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 Apr. 18, 2015, the network reported 9 fireballs.
(9 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 April 18, 2015 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Size
2015 GK
Apr 13
2.8 LD
30 m
2015 HH
Apr 14
11.7 LD
25 m
2015 HJ
Apr 14
9.3 LD
16 m
2015 GA1
Apr 16
2.5 LD
21 m
2015 GL13
Apr 16
0.5 LD
8 m
2015 GY12
Apr 19
13.7 LD
31 m
2015 GB14
Apr 28
8.9 LD
39 m
5381 Sekhmet
May 17
62.8 LD
2.1 km
2005 XL80
Jun 4
38.1 LD
1.0 km
2012 XB112
Jun 11
10.1 LD
2 m
2005 VN5
Jul 7
12.6 LD
18 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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