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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 345.3 km/sec
density: 2.3 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: B8
2112 UT Apr28
24-hr: C2
1158 UT Apr28
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 28 Apr 11
A new sunspot is emerging at the circled location. Credit: SDO/HMI
Sunspot number: 39
What is the sunspot number?
Updated 27 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 27 Apr 2011


The Radio Sun
10.7 cm flux: 108 sfu
explanation | more data
Updated 27 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: 4.6 nT
Bz: 3.1 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 28 Apr 11
A solar wind stream flowing from the indicated coronal hole should reach Earth on April 30th or May 1st. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Apr 28 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
05 %
05 %
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: 2011 Apr 28 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
35 %
MINOR
01 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
35 %
MINOR
01 %
05 %
SEVERE
01 %
01 %
 
Thursday, Apr. 28, 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

VOYAGER'S SURPRISING MESSAGE TO E.T.: NASA's Voyager probes are at the edge of the solar system carrying a message to possible extraterrestrial civilizations. Highlights include greetings from humans and whales, some of Earth's greatest music, and the brainwaves of a young woman in love. Get the full story from Science@NASA.

CORONAL HOLE: NASA's Solar Dynamics Observatory is monitoring a hole in the sun's atmosphere--a "coronal hole." It is the dark region circled in this extreme ultraviolet image taken during the early hours of April 28th:


Above: A composite 171-193-211 Angstrom EUV image from SDO. April 28 @ 06:28 UT

Coronal holes are places where the sun's magnetic field opens up and allows the solar wind to escape. A stream of solar wind flowing from this coronal hole is expected to reach Earth on April 30th-May 1st. NOAA forecasters estimate a 35% chance of geomagnetic activity at that time.

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

KENNEDY WILDFIRE: Forecasters say there is an 80% chance of favorable weather for Friday's scheduled launch of space shuttle Endeavour. The dark clouds over Kennedy Space Center that briefly worried onlookers yesterday were not rain, but smoke:

"Around noon on April 27th, smoke from a nearby wildfire appeared over the launch site," says photographer Jacob Kuiper, one of hundres of journalists on hand to cover the shuttle's liftoff. "The fire spread rapidly, driven by strong southerly winds along the Florida coastline. At one point, huge smoke clouds covered more than half of the skies over KSC. It was a dramatic scene."

Firefighters have the blaze under control, and it is not expected to interfere with an on-time liftoff at 3:47 pm EDT on April 29th.

Endeavour is poised to begin a two week mission to the International Space Station. There it will deliver the Alpha Magnetic Spectrometer--a $1.5 billion cosmic ray detector that could reveal the nature of dark matter and find whole galaxies made of antimatter. The shuttle crew will also test a new automated rendevous system named, appropriately, STORMM, that will help future spacecraft dock to the ISS after the shuttle program is over.

Get ready for Endeavour's last flight: Turn your cell phone into a field-tested shuttle tracker.

  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 28, 2011 there were 1218 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 GJ3
Apr 27
7.7 LD
--
25 m
2008 UC202
Apr 27
8.9 LD
--
10 m
2011 HJ
Apr 28
5.3 LD
--
28 m
2011 HP4
May 1
3.3 LD
--
14 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
--
10 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
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
2009 AV
Aug 22
49.7 LD
--
1.1 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
Conquest Graphics
  for out-of-this-world printing and graphics
Science Central
  cloud server 2
  more links...
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