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Solar wind
speed: 513.5 km/sec
density: 1.3 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: C5
2002 UT Apr21
24-hr: C5
2002 UT Apr21
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 21 Apr 14
Sunspots AR2034, AR2035 and AR2036 have 'beta-gamma' magnetic fields that harbor energy for M-class solar flares. Credit: SDO/HMI
Sunspot number: 192
What is the sunspot number?
Updated 21 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
21 Apr 2014

The Radio Sun
10.7 cm flux: 169 sfu
explanation | more data
Updated 21 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= 4
unsettled
explanation | more data
Interplanetary Mag. Field
Btotal: 5.4 nT
Bz: 2.9 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 21 Apr 14
There are no large 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 21 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
50 %
40 %
CLASS X
10 %
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: 2014 Apr 21 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
30 %
20 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
30 %
30 %
SEVERE
35 %
25 %
 
Monday, Apr. 21, 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

LYRID METEOR SHOWER: Earth is approaching a stream of debris from ancient Comet Thatcher, source of the annual Lyrid Meteor Shower. Usually the shower is mild (10-20 meteors per hour) but unmapped filaments of dust in the comet's tail sometimes trigger outbursts ten times stronger. Forecasters expect this year's peak, however strong it may be, to occur on April 22nd. [meteor gallery]

PEEP-O-NAUTS TAKE RISKY TRIP TO THE EDGE OF SPACE: Yesterday, the students of Earth to Sky Calculus launched a pair of suborbital helium balloons to the stratosphere. One payload carried a radiation sensor to measure the effects of the Easter geomagnetic storm on Earth's upper atmosphere. The other payload carried a colony of halobacteria in an experiment to find out if the extremophiles could live at the edge of space. In honor of the holiday, the students launched some peeps as halobacteria companions. As this movie shows, it's risky being a peep-o-naut:

The near-miss only 2000 ft. above the launch site almost brought an explosive end to the mission. Fortunately, the two balloons carried on to the stratosphere, gathering data on the solar storm in progress during the flight. Here is what peeps look like at the edge of space. Later, the peeps and halobacteria parachuted to Earth, landing in a tree in the Inyo Mountains of central California. Student adventurers recovered the payload and they are studying the data now.

Realtime Space Weather Photo Gallery

GEOMAGNETIC UNREST: As predicted, a CME struck Earth's magnetic field on Easter Sundy. Gusty solar wind conditions in the CME's wake are sparking auroras around the Arctic Circle. Last night, Northern Lights descended as far south as Isabel, South Dakota:

"The aurora grew and sent pulsing pillars across the northern sky above Isabel Lake," says photographer Christian Begeman. "The show only lasted about 10 to 15 minutes. Just 45 minutes later, there was only a faint coloring in the sky."

Meanwhile in the southern hemisphere, the aurora australis reached as far north as Yallingup, Australia. "It was amazing to witness such a rare display from Western Australia!" says photographer Steve Brooks.

NOAA forecasters estimate a 60% chance of geomagnetic activity on April 21st as the solar wind continues to blow. High-latitude sky watchers should remain alert for auroras Aurora alerts: text, voice

Realtime Aurora Photo Gallery


Realtime Eclipse 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. 20, 2014, the network reported 9 fireballs.
(8 sporadics, 1 April Lyrid)

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 21, 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
2014 HW
Apr 27
2.1 LD
9 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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