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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 346.9 km/sec
density: 0.3 protons/cm3
explanation | more data
Updated: Today at 2255 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Dec25
24-hr: A0
2245 UT Dec25
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 25 Dec 07
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 25 Dec 2007
Far side of the Sun:
This holographic image reveals sunspot 978 still intact on the far side of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 1
explanation | more data
Current Auroral Oval:

Switch to: Europe, USA, New Zealand, Antarctica
Updated: 2007 Dec 25 2127 UT
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 3.7 nT
Bz: 2.3 nT north
explanation | more data
Updated: Today at 2256 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: Hinode X-ray Telescope
NOAA Forecasts
Updated at: 2007 Dec 25 2203 UTC
0-24 hr
24-48 hr
01 %
01 %
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 25 2203 UTC
0-24 hr
24-48 hr
10 %
10 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
05 %
05 %
01 %
01 %

What's up in Space
December 25, 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.

THE WORLD AT NIGHT: "I'm pleased to announce a new web site, The World Night At Night," says Iranian photographer and science journalist Babak A. Tafreshi. "It is a photo-collection of the world's most beautiful and historic sites against the nighttime backdrop of stars, planets and celestial events. The eternally peaceful sky looks the same above all nations, attesting to the truly unified nature of Earth as a planet rather than an amalgam of human-drawn territories." The site's galleries are a Christmas treat.

SOLAR ACTIVITY: Sometimes the best solar activity is a sunrise. Consider this one photographed by Xiaowen Yang of Beidaihe Qinghuangdao, China, on Dec. 23rd:

The sun's strange shape is not a flaw in Yang's camera; it's a mirage caused by a gradient in air temperature above the water. Moments before this photo was taken, the spellbound fisherman witnessed an even stranger shape: the omega sun once popularized by science fiction writer Jules Verne. Click to browse the complete sunrise sequence: #1, #2, #3, #4.

Because the sun is so utterly blank and quiet--no sunspots!--sunrises and sunsets are the only solar activity we're likely to see for the rest of the week. A beach is the best place to look.

DIAMOND DUST: Imagine tossing a handful of diamonds into the air and watching them fall back to Earth, tumbling in the sunlight and glittering with all the colors of the rainbow. That's essentially what happened outside Ivar Marthinusen's house in Skedsmokorset, Norway, on Dec. 21st:

Each colored speck in this picture is a mote of diamond dust. "These are jewel-like crystals of ice flashing prismatic colors," explains atmospheric optics expert Les Cowley. Diamond dust crystals form on cold days in the air near ground level. "They are close and we see the individual glints and can even wave our arms to stir them about."

The truly wonderful thing about diamond dust crystals is that when millions of them get together, they can make spectacular halos around the sun. Indeed, "some very nice halos appeared on Dec. 21st," says Marthinusen. "For a while the 22 degree, 46 degree, upper tangent arc and sundogs were all visible."

"The season of diamond dust is upon us in the Northern Hemisphere," adds Cowley. "So check the sky during the icy dawns and days of the next few weeks!"

Comet 8P/Tuttle Photo Gallery
[World Map of Comet Sightings]
[sky map] [comet cameras] [ephemeris] [orbit]

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 25, 2007 there were 912 potentially hazardous asteroids.
Dec-Jan Earth-asteroid encounters:
Miss Distance
2007 XZ9
Dec. 1
8.1 LD
45 m
2007 VD184
Dec. 9
7.8 LD
95 m
3200 Phaethon
Dec. 10
47 LD
5 km
2007 YN1
Dec. 15
1.0 LD
45 m
2007 XH16
Dec. 24
8.1 LD
565 m
2007 TU24
Jan. 29
1.4 LD
400 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, -- This site is penned daily by Dr. Tony Phillips.
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