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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 444.2 km/sec
density: 7.2 protons/cm3
explanation | more data
Updated: Today at 2145 UT
X-ray Solar Flares
6-hr max: A0
2145 UT Jan23
24-hr: A0
0350 UT Jan23
explanation | more data
Updated: Today at: 2145 UT
Daily Sun: 23 Jan 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 22 Jan 2008
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= 1 quiet
24-hr max: Kp= 1
explanation | more data
Current Auroral Oval:

Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 3.7 nT
Bz: 1.7 nT south
explanation | more data
Updated: Today at 2146 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: 2008 Jan 22 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: 2008 Jan 22 2203 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
10 %
10 %
05 %
05 %
01 %
01 %

What's up in Space
January 23, 2008
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.

MERCURY FLYBY: Last week's historic flyby of Mercury by NASA's MESSENGER spacecraft gathered 500 megabytes of data and more than a thousand high-resolution photos covering nearly six million square miles of previously unseen terrain. "Discoveries are at hand," say members of the mission science team. Click here for a hint of things to come.

NACREOUS CLOUDS: People across Scandinavia are still talking about a stunning display of nacreous clouds that rolled over the Arctic Circle on Jan. 19th and 20th. "I have never seen such huge, colourful, mutating clouds," says Kalinka Irina Martín Iglesias who sends this picture from Tunhovdfjorden, Norway:

The display was so bright, she actually used sunglasses as a filter for one of four lovely snapshots.

Nacreous clouds float high above ordinary clouds at altitudes ranging from 9 to 16 miles. Their tiny ice crystals, which diffract sunlight to produce iridescent colors, need exceptionally low temperatures of minus 120 F to form. Because of these extremes, nacreous clouds are rare. Nevertheless, they have appeared several times this season over Scandinavia, raising hopes for more as the cold of winter deepens. The best time to look is around dusk and dawn.

more images: from Richt de Jong of Ørje, Norway; from Johannes Lillegaard Frøyen of Bogstad, Oslo, Norway; from Håkon Dahle of Fjellhamar, Norway; from David Milton of Angered, Sweden.

FORGET THE SKIING... Look for the halos! Ski slopes are excellent places to spot sundogs and other luminous ice halos, which appear when sunlight shines through ice crystals in the air.

Spaceweather reader Mike Conlan sends this report: "Last week, I was skiing on Blackcomb Mountain in Whistler, British Columbia, when I noticed a peculiar bright light below the sun with 'sundogs' on either side of it: photo. A snow storm was diminishing with about 60 km/h winds, so there was a large amount of small-particle snow blowing around." (continued below)

"My friends and I sat and watched the sundogs directly in front of us from the top of the world for quite a while! Luckily I was skiing with my Nikon D200 to capture this unique sight."

The lights that mesmerized Conlan's party are called subparhelia. "Ski slopes let us look downward to see halos normally located below the horizon," says atmospheric optics expert Les Cowley. "Here we have sub-horizon halos made by six-sided plate crystals."

People often think that 'sub-sundogs' are somehow reflections of true sundogs above. Not so, says Cowley. "They are not reflections of the sundogs but are formed by rays following sundog paths that, inside the crystal, happen to collide and reflect from a vertical crystal facet. The subsun directly below the sun can often also be seen on airplane journeys."

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. [comment]
On January 23, 2008 there were 921 potentially hazardous asteroids.
Jan. 2008 Earth-asteroid encounters:
Miss Distance
2005 WJ56
Jan. 10
10.9 LD
1.2 km
2008 AF3
Jan. 13
1.0 LD
27 m
1685 Toro
Jan. 24
76 LD
6.2 km
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...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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