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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: 567.1 km/sec
density: 1.0 protons/cm3
explanation | more data
Updated: Today at 2244 UT
X-ray Solar Flares
6-hr max: B1
1920 UT Dec19
24-hr: B4
0045 UT Dec19
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 19 Dec 07
Sunspot 978 has rotated over the sun's western limb leaving the sun once again blank. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 19 Dec 2007
Far side of the Sun:
This holographic image reveals no sunspots on the farside of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 4
unsettled
explanation | more data
Current Auroral Oval:

Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Updated:
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 4.9 nT
Bz: 0.3 nT north
explanation | more data
Updated: Today at 2245 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: Hinode X-ray Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2007 Dec 19 2203 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: 2007 Dec 19 2203 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
30 %
30 %
MINOR
10 %
10 %
SEVERE
05 %
05 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
30 %
30 %
MINOR
15 %
15 %
SEVERE
05 %
05 %

What's up in Space
December 19, 2007
Where's Saturn? Is that a UFO--or the ISS? What's the name of that star? Get the answers from mySKY--a fun new astronomy helper from Meade.

NOON TRIANGLE: Don't look (because it would really hurt your eyes), but Mercury and Jupiter have gathered around the Sun to form a compact triangle in the noon sky. A coronagraph onboard the Solar and Heliospheric Observatory (SOHO) is monitoring the formation, which will persist for the rest of the week. Join SOHO for a ringside seat.

HISTORIC HALOS: On December 16th, the skies above Oslo, Norway, stunned onlookers with a display of ice halos that "looks set to go down in halo history as one of the greatest," says atmospheric optics expert Les Cowley.

Oslo resident Johannes Froyen describes the scene: "It was a beautiful day with tiny ice crystals falling from a clear sky. As I looked out my window, I was thrilled to see so many arcs and pillars of light." He took these pictures using a Nikon D70:

The cause of the display was sunlight shining through diamond dust--that is, tiny crystals of ice in the air near ground level. "Diamond dust makes the very best halos," says Cowley. "The Oslo display was widely seen and had several rare arcs. The bright V shaped halo touching the 22 degree halo is an upper tangent arc. Outside that, the brightly colored arc is actually two superimposed halos, a supralateral arc made by horizontal pencil-like crystals and a very rare 46 degree halo made by tumbling crystals."

"The season of diamond dust is upon us in the Northern Hemisphere," he says. "Check the sky during the icy dawns and days of the next few weeks!"

ANTICIPATION: Will it turn into a sunspot--or not? That's the question solar physicists around the world are asking themselves this week as a bright knot of reversed-polarity magnetism crosses the face of the sun. On the answer hinges the beginning of a new solar cycle.

Yesterday in Rockville, Maryland, Greg Piepol used his Coronado SolarMax90 to photograph the region of interest:

As explained in a recent story from Science@NASA, new sunspot cycles always begin with a high-latitude, reversed polarity sunspot. This little active region is both high-latitude and reversed polarity. All it has to do to trumpet the start of a new solar cycle is coelesce into a genuine sunspot.

"Hopefully this active region is the harbinger of good news for the new year!" says Piepol, who craves more solar activity than the low ebb we've been experiencing in 2007. Will a new-cycle spot emerge this week? Stay tuned.


2007 Geminid Meteor Gallery
[World Map of Geminid Sightings]
[IMO recap] [meteor alerts] [Night Sky Cameras]

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 19, 2007 there were 912 potentially hazardous asteroids.
Dec-Jan Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2007 XZ9
Dec. 1
8.1 LD
18
45 m
2007 VD184
Dec. 9
7.8 LD
18
95 m
3200 Phaethon
Dec. 10
47 LD
14
5 km
2007 XH16
Dec. 24
8.1 LD
13
565 m
2007 TU24
Jan. 29
1.4 LD
19
405 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 bureau for real-time monitoring of solar and geophysical events, research in solar-terrestrial physics, and forecasting solar and geophysical disturbances.
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.
Daily Sunspot Summaries
  From the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
  more links...
©2007, SpaceWeather.com -- This site is penned daily by Dr. Tony Phillips.
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