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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 308.1 km/sec
density: 0.1 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: C1
2014 UT Apr21
24-hr: C2
0132 UT Apr21
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 21 Apr 12
The solar disk is peppered with sunspots. Chance of M-flares today=30%. Credit: SDO/HMI
Sunspot number: 162
What is the sunspot number?
Updated 20 Apr 2012

Spotless Days
Current Stretch: 0 days
2012 total: 0 days (0%)
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 821 days
Typical Solar Min: 486 days

Updated 20 Apr 2012


The Radio Sun
10.7 cm flux: 142 sfu
explanation | more data
Updated 20 Apr 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 3
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 9.7 nT
Bz: 5.9 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 21 Apr 12
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2012 Apr 21 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
30 %
30 %
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: 2012 Apr 21 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
20 %
MINOR
10 %
10 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
25 %
25 %
MINOR
15 %
15 %
SEVERE
05 %
05 %
 
Saturday, Apr. 21, 2012
What's up in space
 

Can you drop a probe on a comet? A new iPhone game from NASA's Jet Propulsion Laboratory puts you in control of the Rosetta spacecraft as it prepares to intercept Comet 67P/Churyumov-Gerasimenko. Download it now.

 
Comet Quest for iOS

LYRID METEOR SHOWER: The annual Lyrid meteor shower peaks this weekend on the night of April 21-22 when Earth passes through a stream of debris from ancient Comet Thatcher. 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. This year's peak coincides with a new Moon, which has prompted NASA to attempt an unusual 3D meteor photography experiment. Browse the links for more information: observing tips, meteor radar, NASA chat, 3D meteors, Lyrid video.

SUNSPOT GENESIS: The solar disk is peppered with sunspots and at least three of them are crackling with C-class solar flares. Make that four. A new sunspot, AR1465, has just broken through the stellar surface to join the action. Cai-Uso Wohler photographed the emergence from his backyard observatory in Bispingen, Germany:

NOAA forecasters estimate a 30% chance of an M-class flare during the next 24 hours. As the youngest and least stable of the sunspots, AR1465 is the most likely source. Stay tuned for solar activity. Solar flare alerts: text, voice.

more images: from the Charlie Bates Solar Astronomy Project of Washington, DC; from Jim Werle of Henderson, Nevada; from Alan Friedman of Buffalo, NY; from Jett Aguilar of Quezon City, Philippines

INCOMING PLASMA CLOUDS: On April 18th and 19th, a series of minor CMEs puffed away from the sun. Three of them are heading in our general direction. Analysts at the Goddard Space Weather Lab have prepared an animated forecast track of the ensemble:

According to the forecast, the clouds are going to hit Mercury, Earth, Mars and rover Curiosity en route to Mars. The impact on our planet, on April 22nd around 00:50 UT, is expected to be minor with auroras likely only at higher latitudes. Aurora alerts: text, voice.

ARCTIC AURORA RECAP: As the midnight sun returns to the Arctic, northern sky watchers are looking back on the 2011-2012 aurora season with pleasure. "There has definitely been increased activity this season as the solar cycle heads toward a maximum in 2013," says photographer Ole C. Salomonsen. "To commemorate the season I have assembled a video from photos I took in northern parts of Norway, Finland and Sweden from fall 2011 to spring 2012." Click to play:

.

"This video marks the end of a very exciting aurora season for me," says Salomonsen. "It has made me very excited for the upcoming season (autumn 2012), and what it has to offer in terms of celestial lights and experiences!"

This doesn't mean that auroras are gone for everyone. The Arctic Circle may be brightening with summer sunlight, but lower latitudes still have enough darkness for Northern Lights. Indeed, upper-middle latitude sky watchers should be alert for auroras on April 20th. NOAA forcasters estimate a 35% chance of geomagnetic activity as Earth enters a region of negative polarity IMF.

  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, 2012 there were 1287 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2007 HV4
Apr 19
4.8 LD
--
8 m
2012 GP1
Apr 21
9 LD
--
26 m
2012 HN1
Apr 21
5.2 LD
--
18 m
2012 HE
Apr 22
6.9 LD
--
32 m
2012 HE2
Apr 24
8.9 LD
--
29 m
2012 HQ
Apr 24
9.8 LD
--
42 m
2012 HM
Apr 28
1.4 LD
--
68 m
2011 WV134
Apr 28
38.6 LD
--
1.6 km
1992 JD
May 2
9.5 LD
--
43 m
2010 KK37
May 19
2.3 LD
--
31 m
4183 Cuno
May 20
47.4 LD
--
5.7 km
2002 VX94
May 26
72.8 LD
--
1.1 km
2002 AC
Jun 16
62.2 LD
--
1.2 km
1999 BJ8
Jun 16
68.8 LD
--
1.1 km
2005 GO21
Jun 21
17.1 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
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  more links...
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