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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 509.0 km/sec
density: 1.3 protons/cm3
explanation | more data
Updated: Today at 2245 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Jan21
24-hr: A0
2245 UT Jan21
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 21 Jan 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 21 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: 4.0 nT
Bz: 0.5 nT south
explanation | more data
Updated: Today at 2246 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: Hinode X-Ray Telescope.
NOAA Forecasts
Updated at: 2008 Jan 21 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 21 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 21, 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.

MOTHER OF PEARL! This weekend, Scandinavians witnessed a veritable storm of nacreous clouds. "It was a stunning display," says Håkon Dahle who snapped this picture from Fjellhamar, Norway:

Photo details: Nikon D70, ISO 200, 1/60s exposure

"The show lasted about an hour," adds Johannes Lillegaard Frøyen of nearby Oslo. "I was walking along a frozen lake. The clouds were so bright, they reflected from the ice and made the solid lake resemble a wavy ocean. I took these pictures using my Nikon D70."

Nacreus clouds--also known as "Mother of Pearl" clouds--exist way above ordinary clouds and weather at altitudes 9 to 16 miles high. Their tiny ice crystals, which give them their iridescent colors, need exceptionally low temperatures of minus 85 Celsius (-120 F) to form. Because of these extremes, nacreus clouds are rare. Nevertheless, they have appeared two nights in a row over Scandinavia, raising hopes for more tonight. Photographers, ready your cameras!

more images: from Kalinka Irina Martín Iglesias of Tunhovdfjorden, Buskerud, Norway; from Tor Einar Aslesen of Oslo, Norway; from Ragnar Johnskås of Ringsaker, Norway; from Lars Helge Stølen of Sande i Vestfold, Norway; from David Milton of Angered, Sweden; from Morten Ross of Sandbukta, Norway; from Derick Rethans of Skien, Telemark, Norway; from Toby Rutland of Gothenburg, Sweden.

HOLMES AND ALGOL: Moonlight may spoil the show, but for astrophotographers with clear skies, it's worth a shot: Comet 17P Holmes is passing directly in front of variable star Algol. Tom J. Martinez of Cleveland, Missouri, photographed the pair converging on Jan. 14th:

Full Moon inserted to show the angular scale of the comet: photo details.

Tonight, Algol shines through some of the thickest parts of the comet's atmosphere, prompting reader Doug Zubenel to wonder "will we see a halo around Algol?" Here on Earth tiny grains of dust and crystals of ice in the air produce halos around bright stars and planets. Perhaps comet dust will do the same to Algol.

Probably not--but its something fun to look for on a cold moonlit night. After sunset, slew your telescope to Algol and let the hunt begin: sky map.

Comet 17P/Holmes Photo Gallery
[World Map of Comet Sightings]
[sky map] [ephemeris] [3D orbit] [comet binoculars]

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 21, 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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