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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 332.9 km/sec
density: 1.3 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B7
2300 UT Apr27
24-hr: C2
0233 UT Apr27
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 27 Apr 11
New sunspot 1199 is growing rapidly. Credit: SDO/HMI
Sunspot number: 57
What is the sunspot number?
Updated 26 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 26 Apr 2011


The Radio Sun
10.7 cm flux: 109 sfu
explanation | more data
Updated 26 Apr 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 1
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 4.3 nT
Bz: 2.7 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 27 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 27 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 27 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
 
Wednesday, Apr. 27, 2011
What's up in space
 

Are we alone? Your iPhone has the answer. Download the all-new Drake Equation app to calculate the population of the Milky Way.

 
DrakeEQ for iPhone and iPad

FAST GROWING SUNSPOT: New sunspot 1199 is growing rapidly in the sun's northern hemisphere, ballooning in area by more than a factor of five during the last 24 hours: movie. If the expansion continues apace, this active region could soon pose a threat for flares. Stay tuned.

STORMY SHUTTLE: The final flight of space shuttle Endeavour is nigh, but only if the clouds part. Jacob Kuiper sends this stormy picture from the Kennedy Space Center on April 26th:

"We are experiencing unstable weather conditions just three days ahead of the launch of Endeavour, currently scheduled for Friday, April 29th, at 3:47 pm EDT," says Kuiper. "Weather conditions in the coming 72 hours will change, but there could be more thunderstorms right up until the big moment."

WEATHER UPDATE (April 27 @ 11 am EDT): The latest forecast calls for an 80 percent chance of favorable conditions at launch time, according to Shuttle Weather Officer Kathy Winters. The only concern for launch may be the crosswinds at the Shuttle Landing Facility.

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.

'B' STANDS FOR ... BORING? On the Richter Scale of solar flares, B-class eruptions are weak and generally considered boring. Really? Consider the following B-class eruption recorded by NASA's Solar Dynamics Observatory (SDO) on April 23rd:

That wasn't boring. On the contrary, the blast hurled hundreds of thousands of tons of plasma above the stellar surface with a power akin to millions of atomic bombs. The only thing more amazing than the blast was its aftermath. For all that power, the explosion was insufficient to break the plasma free from the sun's grasp. Magnetic fields arcing above underlying sunspot 1193 held tight to the expanding gas and pulled it back down with a dynamic double bounce.

One of the most significant findings from SDO, barely a year after First Light, is that there are no truly boring solar flares. The observatory's Hubble-like cameras have revealed hidden power and fascination in even the smallest eruptions, leaving us waiting with anticipation for the next B-flare. Stay tuned.


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 27, 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
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
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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