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Solar wind
speed: 489.0 km/sec
density: 3.5 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: C1
2002 UT Apr18
24-hr: M7
1303 UT Apr18
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 18 Apr 14
Sunspots AR2035, AR2036 and AR2037 have 'beta-gamma' magnetic fields that harbor energy for M-class solar flares. Credit: SDO/HMI
Sunspot number: 296
What is the sunspot number?
Updated 18 Apr 2014

Spotless Days
Current Stretch: 0 days
2014 total: 0 days (0%)
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%)

Update
18 Apr 2014

The Radio Sun
10.7 cm flux: 179 sfu
explanation | more data
Updated 18 Apr 2014

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 9.1 nT
Bz: 6.4 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 18 Apr 14
There are no large equatorial coronal holes on the Earthside of the sun. Credit: SDO/AIA.

Spaceweather.com posts 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: 02-28-2014 16:55:02
SPACE WEATHER
NOAA Forecasts
Updated at: 2014 Apr 18 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
60 %
60 %
CLASS X
10 %
10 %
Geomagnetic Storms:
Probabilities for significant disturbances in Earth's magnetic field are given for three activity levels: active, minor storm, severe storm
Updated at: 2014 Apr 18 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
40 %
40 %
MINOR
15 %
35 %
SEVERE
01 %
10 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
05 %
MINOR
25 %
20 %
SEVERE
55 %
75 %
 
Friday, Apr. 18, 2014
What's up in space
 

When is the best time to see auroras? Where is the best place to go? And how do you photograph them? These questions and more are answered in a new book, Northern Lights - a Guide, by Pal Brekke & Fredrik Broms.

 
Northern Lights - a Guide

NASA SPACECRAFT HITS THE MOON: There's a new crater on the Moon. NASA's LADEE spacecraft, on a mission since Sept. 2013 to study the lunar atmosphere, has crashed. This event was deliberate. LADEE was near the end of its planned mission and the grazing impact gave researchers a chance to study "lunar air" very close to the Moon's surface: full story.

M7-CLASS SOLAR FLARE (UPDATED): Sunspot AR2036 erupted today, April 18th, at 1307 UT, producing a strong M7-class solar flare. NASA's Solar Dynamics Observatory recorded the extreme ultraviolet flash:

An S1-class radiation storm is underway in the aftermath of the flare. However, this is a relatively minor storm which poses minimal threat to satellites and aircraft.

Of greater interest is a CME that emerged from the blast site. The Solar and Heliospheric Observatory recorded the storm cloud racing away from the sun at aproximately 800 km/s:

This CME could deliver a glancing blow to Earth's magnetic field on or about April 20th. Two or three minor CMEs are expected to preceed this on April 18th-19th, and the combined impacts could generate a geomagnetic storm during the weekend. High-latitude sky watchers should be alert for auroras. Solar flare alerts: text, voice

Realtime Space Weather Photo Gallery

THE TURQUOISE FRINGE: Lunar eclipses are supposed to be red, yet when the Moon passed through Earth's amber shadow on April 15th, many observers witnessed a softly-glowing band of turquoise blue. Robert and Elisabeth Slobins send this picture of the phenomenon from Fort Myers, Florida:

The source of the turquoise is ozone. Prof. Richard Keen, an atmospheric scientist from the University of Colorado explains: "During a lunar eclipse, most of the light illuminating the Moon passes through the stratosphere, and is reddened by scattering. However, light passing through the upper stratosphere penetrates the ozone layer, which absorbs red light and actually makes the passing light ray bluer!" This can be seen, he says, as a turquoise fringe around the red.

For years, Keen has been using lunar eclipses to probe the transparency of the stratosphere. When the stratosphere is clogged with volcanic ash and other aerosols, lunar eclipses tend to be dark red. The bright orange color of the April 15th eclipse, along with the ready visibility of the turquoise fringe, suggests that the stratosphere is clear. This is a key finding for climate change models.

To see the effects of ozone on the eclipse, you have to be looking at just the right moment. Readers are invited to browse the gallery for more examples:

Realtime Eclipse Photo Gallery


Realtime Aurora Photo Gallery


Realtime Mars 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. 17, 2014, the network reported 6 fireballs.
(6 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, 2014 there were 1465 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Size
2007 TV18
Apr 18
7.4 LD
88 m
2014 GG49
Apr 19
3.9 LD
31 m
2007 HB15
Apr 28
6.7 LD
12 m
2010 JO33
May 17
4 LD
43 m
2005 UK1
May 20
36.7 LD
1.1 km
1997 WS22
May 21
47.1 LD
1.5 km
2002 JC
May 24
48.7 LD
1.4 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
Space Weather Alerts
   
  more links...
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