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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 372.6 km/sec
density: 0.4 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: B2
1714 UT Mar18
24-hr: B5
0405 UT Mar18
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 18 Mar 11
Sunspot 1173 is growing slowly. So far it poses no threat for strong flares. Credit: SDO/HMI
Sunspot number: 45
What is the sunspot number?
Updated 17 Mar 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 17 Mar 2011


The Radio Sun
10.7 cm flux: 90 sfu
explanation | more data
Updated 17 Mar 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: 3.8 nT
Bz: 1.1 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 18 Mar 11
There are no large coronal holes on the Earth-side of the sun. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Mar 18 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
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 Mar 18 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
 
Friday, Mar. 18, 2011
What's up in space
 

Turn your cell phone into a field-tested satellite tracker. Works for Android and iPhone.

 
Satellite flybys

HISTORIC FIRST: For the first time ever, a spacecraft has gone into orbit around Mercury. NASA's MESSENGER probe is now circling the solar system's innermost planet, poised to reveal a world that is both akin to Earth and shockingly alien. Get the full story from Science@NASA.

MAGNETIC FILAMENT: A long and sinuous filament of magnetism is snaking over the sun's western limb. NASA's Solar Dynamics Observatory captured the 200,000 km-long structure in mid-twist on the morning of March 18th:

Long filaments like this one are often unstable. If this one erupts, it could hurl pieces of itself toward Earth. More likely, the filament will continue to wind over the western limb, active but intact. Either way it's a good show. Readers with solar telescopes are encouraged to monitor developments.

PARTING SHOT: Departing sunspot 1169 erupted during the late hours of March 16th and hurled a spectacular coronal mass ejection (CME) over the sun's western limb. Click on the image to play a movie of the expanding cloud:

Only a week ago, sunspot 1169 was squarely facing our planet. If the eruption had occurred then, we'd be expecting bright auroras and geomagnetic storms before the weekend. Instead, this CME will sail wide right of Earth with negligible effect. Maybe next time.

more images: from John Nassr of Baguio, Philippines; from Monty Leventhal OAM of Sydney. Australia.


March 2011 Aurora Photo Gallery
[previous Marches: 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 March 18, 2011 there were 1204 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 EB74
Mar 16
0.9 LD
--
18 m
2011 BE38
Apr 10
48 LD
--
1.0 km
2002 DB4
Apr 15
62.5 LD
--
2.2 km
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
--
1.1 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
   
  more links...
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