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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 332.8 km/sec
density: 4.6 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: C1
1919 UT Apr17
24-hr: C1
1415 UT Apr17
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 17 Apr 11
Sunspots 1190 and 1193 have "beta-gamma" magnetic fields that harbor energy for M-class flares. Credit: SDO/HMI
Sunspot number: 97
What is the sunspot number?
Updated 16 Apr 2011

Spotless Days
Current Stretch: 0 days
2011 total: 1 day (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 820 days
Typical Solar Min: 486 days

Updated 16 Apr 2011


The Radio Sun
10.7 cm flux: 119 sfu
explanation | more data
Updated 16 Apr 2011

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: 3.1 nT
Bz: 2.8 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 17 Apr 11
A solar wind stream flowing from the indicated coronal hole should reach Earth sometime around April 20th. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Apr 17 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: 2011 Apr 17 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
 
Sunday, Apr. 17, 2011
What's up in space
 

They came from outer space--and you can have one! Genuine meteorites are now on sale in the Space Weather Store.

 
Own your own meteorite

SPROUTING GRASS MOON: According to folklore, tonight's full Moon has a special name--the "Sprouting Grass Moon" because it shines down on the new grasses of northern spring. Fun: Go outside after dark and look at the ground. Does the grass look green or blue? The answer may surprise you.

STRANGE BEAUTY: It's been almost a year since NASA's Solar Dynamics Observatory began taking pictures of the sun. As the first anniversary of First Light approaches on April 21st, researchers are taking stock of the observatory's many accomplishments. One of the most profound results turns out to be aesthetic: the sun is more beautiful than anyone imagined. Consider the following extreme ultraviolet image, taken just hours ago, of the magnetic canopy of sunspot complex 1191-1193:

This stunning snapshot is actually routine material for SDO. The observatory produces a daily torrent of beauty that, even now, mission scientists haven't grown used to. Normally unflappable researchers are frequently caught staring slack-jawed at SDO movies. And when they're done, they don't have the vocabulary to describe what they have seen. Many of the phenomena SDO catches have no textbook names. SDO's starscapes may turn out to be as prized to poets, artists, and writers as they are to no-nonsense solar physicists. See for yourself.

SUN-EARTH CONNECTION: Even a small solar flare can reach out and touch the Earth. On April 16th, sunspot 1190 produced a relatively minor C5-class flare. X-rays from the distant explosion broke apart molecules in Earth's upper atmosphere, creating a wave of ionization over Europe. Researcher Rob Stammes detected the sudden ionospheric disturbance or "SID" using a very low frequency radio receiver at the Polar Light Center in Lofoten, Norway:

The wave of ionization allowed signals from a terrestrial radio station to bounce over the horizon into Stamme's 23.4 kHz VLF antenna. That's what's shown in the upper panel. Now consider the lower panel: "There was also a small increase in radio noise directly from the flare itself at 56.25 MHz," points out Stammes. "Contact with the sun at VLF and VHF radio frequencies at the same moment gives me important information."

Readers, would you like to be in radio contact with the sun? Visit NASA's RadioJove web site for instructions.


April 2011 Aurora Gallery
[previous Aprils: 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002]

  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 17, 2011 there were 1218 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 GP59
Apr 15
1.4 LD
--
58 m
2002 DB4
Apr 15
62.5 LD
--
2.2 km
2011 GE
Apr 13
4.8 LD
--
28 m
2011 GP59
Apr 15
1.4 LD
--
58 m
2002 DB4
Apr 15
62.5 LD
--
2.2 km
2011 GJ3
Apr 27
7.7 LD
--
24 m
2008 UC202
Apr 27
8.9 LD
--
10 m
2009 UK20
May 2
8.6 LD
--
23 m
2008 FU6
May 5
75.5 LD
--
1.2 km
2003 YT1
May 5
65.3 LD
--
2.5 km
2011 GJ3
Apr 27
7.7 LD
--
24 m
2008 UC202
Apr 27
8.9 LD
--
10 m
2009 UK20
May 2
8.6 LD
--
23 m
2008 FU6
May 5
75.5 LD
--
1.2 km
2003 YT1
May 5
65.3 LD
--
2.5 km
2002 JC
Jun 1
57.5 LD
--
1.6 km
2009 BD
Jun 2
0.9 LD
--
9 m
2002 JB9
Jun 11
71.5 LD
--
3.2 km
2001 VH75
Jun 12
42.2 LD
--
1.1 km
2004 LO2
Jun 15
9.9 LD
--
48 m
2001 QP181
Jul 2
35.1 LD
--
1.0 km
2011 GA55
Jul 6
63.9 LD
--
1.0 km
2011 EZ78
Jul 10
37.3 LD
--
1.5 km
2003 YS117
Jul 14
73.9 LD
--
1.0 km
2007 DD
Jul 23
9.3 LD
--
31 m
2002 JC
Jun 1
57.5 LD
--
1.6 km
2009 BD
Jun 2
0.9 LD
--
9 m
2002 JB9
Jun 11
71.5 LD
--
3.2 km
2001 VH75
Jun 12
42.2 LD
--
1.1 km
2004 LO2
Jun 15
9.9 LD
--
48 m
2001 QP181
Jul 2
35.1 LD
--
1.0 km
2011 GA55
Jul 6
63.9 LD
--
1.0 km
2011 EZ78
Jul 10
37.3 LD
--
1.5 km
2003 YS117
Jul 14
73.9 LD
--
1.0 km
2007 DD
Jul 23
9.3 LD
--
31 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
Conquest Graphics
  for out-of-this-world printing and graphics
Science Central
   
  more links...
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