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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 414.1 km/sec
density: 1.4 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B2
2020 UT Dec17
24-hr: B7
1510 UT Dec17
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 17 Dec. 09
Sunspot 1035 poses a threat for M-class solar flares. It is a member of new Solar Cycle 24. Credit: SOHO/MDI
Sunspot number: 30
What is the sunspot number?
Updated 16 Dec 2009

Spotless Days
Current Stretch: 0 days
2009 total: 259 days (74%)
Since 2004: 770 days
Typical Solar Min: 485 days
explanation | more info
Updated 16 Dec 2009

Far side of the Sun:
This holographic image reveals no sunspots on the far side of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 1
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 4.1 nT
Bz: 1.1 nT north
explanation | more data
Updated: Today at 2345 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Dec 17 2201 UTC
0-24 hr
24-48 hr
10 %
10 %
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: 2009 Dec 17 2201 UTC
0-24 hr
24-48 hr
05 %
15 %
01 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
05 %
20 %
01 %
10 %
01 %
01 %
What's up in Space
December 17, 2009

ASTRONOMY ALERTS: Looking for a unique and affordable gift? Give the heavens for Christmas at Spaceweather PHONE.


WHEN AURORAS COLLIDE: A continent-wide network of all-sky cameras has photographed a never before seen phenomenon: colliding auroras that produce explosions of light. The must-see images have solved a long-standing mystery of Northern Lights. Get the full story from Science@NASA.

CURIOUS EVENTS IN NEBRASKA: "Last night, Dec. 16th at 9 p.m. CST, a very bright meteor lit up the completely overcast sky like lightning in southeast Nebraska," reports Trooper Jerry Chab of the Nebraska State Patrol. "It flashed for approximately 2 seconds and was followed by sonic booms and ground shaking, which prompted many calls by the public to law enforcement in a three county wide area." Meanwhile, the USGS says there was a magnitude 3.5 earthquake near Auburn, Nebraska, at 8:53 pm, about the same time and place as the fireball. This map shows the nominal epicenter:

"If the earthquake is confirmed, as it appears to be, I think we have the most cosmic of coincidences: A large fireball around the same time of an earthquake," says Chab. "I am simply amazed!"

One possible interpretation of these events is that a small asteroid hit Earth's atmosphere and caused the ground to shake when it exploded in mid-air. However, the timing might not be right. The quake seems to have preceded the fireball. Several readers have pointed out studies that associate lightning-like phenomena with earthquakes: #1, #2, #3. So, the earthquake might be responsible for both the shaking and the light show. Or it might be a big coincidence just as Chab suggests.

More reports could help sort out the possibilities. Readers in Nebraska with photos or eyewitness accounts are encouraged to submit their observations.

Eyewitness Fireball-Quake Reports
[Related news reports: #1, #2 ]

THREE DAYS ON THE SUN: Three days ago, the surface of the sun was calm and almost featureless. Then sunspot 1035 burst onto the scene. A movie from the Solar and Heliospheric Observatory shows developments from Dec. 14th to the present:

The recently invisible spot is now nine times wider than Earth and crackling with C-class solar flares. A series of eruptions on Dec. 16th sent two and perhaps three coronal mass ejections (CMEs) in the general direction of our planet. High-latitude sky watchers should be alert for auroras when the clouds arrive beginning on Dec. 18th or 19th.

(updated) more images: from Richard Best of Lewes, Sussex, England; from A. Berry and J. Stetson of South Portland,Maine; from John C McConnell of Maghaberry Northern Ireland; from Karzaman Ahmad of Langkawi National Observatory, Malaysia; from Monty Leventhal OAM of Sydney, Australia; from Michael Rosolina of White Sulphur Springs, WV; from Gianfranco Meregalli of Milano, Italy; from Mustafa Erol of Antalya/Turkey; from Fabio Mariuzza of Biauzzo, Italy; from Stephen Ames of Hodgenville, KY;

2009 Geminid Meteor Gallery
[sky map] [meteor radar] [Geminid counts]

December Northern Lights Gallery
[previous Decembers: 2008, 2007, 2006, 2005, 2001, 2000]

Explore the Sunspot Cycle

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 17, 2009 there were 1089 potentially hazardous asteroids.
Dec. 2009 Earth-asteroid encounters:
Miss Distance
2009 WV25
Dec. 1
2.9 LD
65 m
2009 WA52
Dec. 5
8.2 LD
23 m
2002 WP
Dec. 6
71.2 LD
950 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 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 and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Daily Sunspot Summaries
  from the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
Science Central
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.













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