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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 305.5 km/sec
density: 3.4 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: B5
1723 UT Dec08
24-hr: C1
0159 UT Dec08
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 08 Dec 11
Two new active regions (circled above) are emerging over the eastern limb. Credit: SDO/HMI
Sunspot number: 122
What is the sunspot number?
Updated 07 Dec 2011

Spotless Days
Current Stretch: 0 days
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 07 Dec 2011


The Radio Sun
10.7 cm flux: 149 sfu
explanation | more data
Updated 07 Dec 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: 4.2 nT
Bz: 3.1 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 08 Dec 11
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Dec 08 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
10 %
10 %
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 Dec 08 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
10 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
 
Thursday, Dec. 8, 2011
What's up in space
 

Don't just watch shooting stars. Wear them! Authentic meteorite jewelry for Christmas is now available in the SpaceWeather Store.

 
Meteorite jewelry

TOTAL LUNAR ECLIPSE: Mark your calendar. On Saturday, Dec. 10th, the full Moon will glide through the coppery shadow of Earth, producing a total lunar eclipse visible from the Pacific side of our planet. For residents of the western USA and Canada, the event unfolds at dawn and will be magnified to super-sized proportions by the Moon illusion. [Science@NASA: full story, video]

SOLAR ACTIVITY: After days of quiet, two new active regions are rotating over the sun's eastern limb, heralding a possible uptick in solar activity. One of them erupted during the late hours of Dec. 7th, shown here in a movie from NASA's Solar Dynamics Observatory:

The untwisting magnetic filament hurled a fragment of itself into space but Earth was not in the line of fire.

The potential of these regions for more eruptions will become clearer as they turn toward Earth in the days ahead. For now, NOAA forecasters estimate a 20% chance of M-class solar flares during the next 24 hours. Solar flare alerts: text, phone.

CONGESTED INTERSECTION: Ranging in size from microscopic space dust to mountainous asteroids, trillions of meteoroids zing through the inner solar system on a daily basis. What are the odds that five of them would cross the same point in space? Pretty good, actually. In fact, it happened just last night. Regard the following orbit diagram, then read on for an expanation:

These are the orbits of five objects that hit Earth on the night of Dec. 7/8. NASA’s All Sky Fireball Network recorded the meteoroids as they disintegrated in the atmosphere over the United States, each one producing a bright fireball. Note how all the orbits converge on a single point--our planet.

Every night the network's cameras scan the skies over the United States, forming an inventory of what hits the atmosphere. Combining images from multiple cameras, network software rapidly calculates the basic parameters of each interloper: orbit, speed, disintegration height, and more. At the moment, cameras are located in only four states (New Mexico, Alabama, Georgia, Tennessee), but the network is expanding to provide even better coverage. Soon we'll see just how congested our intersection in space really is. Stay tuned.

  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 December 8, 2011 there were 1272 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 WV74
Dec 2
2.3 LD
--
13 m
2011 WU74
Dec 4
4.2 LD
--
23 m
2003 XV
Dec 7
1.1 LD
--
21 m
2003 WM7
Dec 9
47.6 LD
--
1.6 km
2000 YA
Dec 26
2.9 LD
--
80 m
2011 SL102
Dec 28
75.9 LD
--
1.0 km
2011 WS95
Dec 28
7.2 LD
--
49 m
1991 VK
Jan 25
25.3 LD
--
1.9 km
433 Eros
Jan 31
69.5 LD
--
8.5 km
2009 AV
Feb 16
44.9 LD
--
1.2 km
2000 ET70
Feb 19
17.7 LD
--
1.0 km
2011 CP4
Feb 23
9.1 LD
--
255 m
2008 EJ85
Mar 6
9.1 LD
--
44 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
Science Central
Trade Show Displays
   
  more links...
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