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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 367.6 km/sec
density: 3.7 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: B7
1805 UT Dec09
24-hr: C3
1320 UT Dec09
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 09 Dec 11
The face of the sun is peppered with spots, but none poses a threat for strong solar flares. Credit: SDO/HMI
Sunspot number: 142
What is the sunspot number?
Updated 08 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 08 Dec 2011

The Radio Sun
10.7 cm flux: 145 sfu
explanation | more data
Updated 08 Dec 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 9.4 nT
Bz: 2.9 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 09 Dec 11
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Dec 09 2200 UTC
0-24 hr
24-48 hr
20 %
20 %
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 09 2200 UTC
0-24 hr
24-48 hr
05 %
13 %
01 %
03 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
20 %
13 %
15 %
08 %
05 %
Friday, Dec. 9, 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: 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 (map). 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. Get the full story from Science@NASA. [Live webcasts: Hong Kong; India; North Dakota; Nevada] [Eclipse animations: #1, #2]

...AND A TOTALLY DIFFERENT ECLIPSE: Last night, NASA's Solar Dynamics Observatory (SDO) observed an unusual event on the sun: An erupting cloud of plasma was eclipsed by a dark magnetic filament. Play the movie for a visual explanation:

The source of the explosion is a farside active region due to turn toward Earth in a few days. For now, though, the blast site lies just behind the sun's eastern limb--perfectly situated for this rare kind of eclipse. Note the filament of relatively cool dark material snaking across the sun's surface in the foreground. That filament partially blocks our view of hot plasma exploding behind it. By studying how the light of the explosion is filtered by the foreground material, SDO mission scientists might be able to learn something new about dark filaments on the sun.

PHOBOS GRUNT UPDATE: Russian Mars probe Phobos Grunt, stranded in Earth orbit since its main engines failed to fire after launch on Nov. 8th, is beginning to sink back into the atmosphere. Analysts expect re-entry to occur sometime in early to mid-January 2012. Until then, it is possible to see the doomed probe zipping brightly across the night sky. Kevin Fetter video-recorded this pass over his home in Brockville, Canada, on Dec. 8th:

In the video, Phobos Grunt was shining about as brightly as a 3rd-magnitude star, but it can get much brighter than that. Tom Smith watched it fly over Anaheim, California, during the early hours of Dec. 9th: "Phobos Grunt was brighter than the 1st-magnitude star Deneb and moving noticeably faster than the International Space Station," he reports.

Ready to see for yourself? Check SpaceWeather's online Satellite Tracker or your smartphone for Phobos Grunt flyby times.

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 seven 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 seven objects that hit Earth on the night of Dec. 8/9. 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 9, 2011 there were 1272 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
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.
  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
  the underlying science of space weather
Science Central
Trade Show Displays
  more links...
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