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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
SPACE WEATHER
Current conditions
Solar wind
speed: 401.9 km/sec
density: 1.4 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: C5
1855 UT Dec18
24-hr: C5
1855 UT Dec18
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 18 Dec. 09
Sunspot 1035 is a member of new Solar Cycle 24. Credit: SOHO/MDI
Sunspot number: 24
What is the sunspot number?
Updated 17 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 17 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
quiet
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Interplanetary Mag. Field
Btotal: 5.6 nT
Bz: 1.9 nT south
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
SPACE WEATHER
NOAA Forecasts
Updated at: 2009 Dec 18 2201 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: 2009 Dec 18 2201 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
45 %
MINOR
05 %
15 %
SEVERE
01 %
05 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
50 %
MINOR
10 %
20 %
SEVERE
01 %
10 %
What's up in Space
December 18, 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.

GREAT SUNSPOT: Sunspot 1035 is putting on a good show. There are two planet-sized cores connected by sinuous magnetic filaments more than 100,000 km long, all surrounded by a seething froth of hot plasma. "It's great," says Paul Haese, who sends this picture from his backyard observatory in Blackwood, Australia:

"This is the best spot of the new solar cycle so far," he says. "I photographed it this morning using a Coronado Solarmax 60."

On Dec. 16th, magnetic fields around the sunspot erupted and hurled a coronal mass ejection toward Earth. The billion-ton cloud is still en route. High-latitude sky watchers should be alert for auroras when it arrives on Dec. 18th or 19th.

more images: from Matt Wastell of Paddington, Brisbane, Australia; from Pete Lawrence of Selsey, West Sussex, UK; from Fulvio Mete of Rome, Italy; 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;

CURIOUS EVENTS IN NEBRASKA: Earthquakes don't rock Nebraska very often. In fact, seismically speaking, it is one of the quietest places in North America. Nevertheless, on Dec. 16th at 8:54 pm CST, USGS seismographs detected a magnitude 3.5 temblor centered near Auburn, Nebraska:


Click to view earthquake details and Nebraska seismic probabilities

"It sounded like those loud grain haulers that drive by, but about five times louder," reports Laurie Riley, who lives near the epicenter. "The whole house shook. My kids came running down stairs – they were scared. It even moved my car, [which was parked outside on icy ground]."

And then the really curious thing happened.

Minutes after the quake, around 9 pm CST, lightning-like flashes lit up the skies around the area of the quake. Telephones in police departments and TV stations rang with reports of bright lights, loud rumbles and shaking ground. Sky watchers, not only in southeastern Nebraska, but also in neighboring Oklahoma, Missouri and Kansas, saw a "bright fireball" with "green streamers" moving from northwest to southeast.

Could these events be connected? Nebraska State Trooper Jerry Chab, an experienced amateur astronomer who witnessed the lights and was one of the first to report them, says no. "I think we have the most cosmic of coincidences: A bright [meteoritic] fireball around the same time as an earthquake." Indeed, eyewitness descriptions of the fireball are consistent with a meteoroid disintegrating in the atmosphere. On the other hand, several readers have pointed out scientific studies that associate lightning-like phenomena (including ball lightning) with earthquakes: #1, #2, #3. The fireball, they suggest, might have been a rare manifestation of "earthquake lightning."

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

Eyewitness Fireball-Quake Reports


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 18, 2009 there were 1089 potentially hazardous asteroids.
Dec. 2009 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2009 WV25
Dec. 1
2.9 LD
16
65 m
2009 WA52
Dec. 5
8.2 LD
20
23 m
2002 WP
Dec. 6
71.2 LD
16
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.
STEREO
  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...
   
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