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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 593.2 km/sec
density: 3.8 protons/cm3
explanation | more data
Updated: Today at 2244 UT
X-ray Solar Flares
6-hr max: B5
2240 UT Dec17
24-hr: C2
0715 UT Dec17
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 17 Dec 07
Sunspot 978 vanishing over the sun's western limb. Credit: SOHO/MDI
Sunspot number: 28
What is the sunspot number?
Updated 15 Dec 2007
Far side of the Sun:
This holographic image reveals one possible sunspot on the farside of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 4
explanation | more data
Current Auroral Oval:

Switch to: Europe, USA, New Zealand, Antarctica
Updated: 2007 Dec 17 2109 UT
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 7.1 nT
Bz: 4.3 nT south
explanation | more data
Updated: Today at 2245 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on Dec. 17th or 18th. Credit: Hinode X-ray Telescope
NOAA Forecasts
Updated at: 2007 Dec 17 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 17 2203 UTC
0-24 hr
24-48 hr
50 %
50 %
20 %
20 %
05 %
05 %
High latitudes
0-24 hr
24-48 hr
50 %
50 %
25 %
25 %
10 %
10 %

What's up in Space
December 17, 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.

AURORA WATCH: Sky watchers, be alert for auroras. Earth is entering a solar wind stream and this is causing high-latitude geomagnetic storms.

CLOSE ENCOUNTER: Ready your telescopes! On Tuesday evening, Dec. 18th, Mars makes its closest approach to Earth until the year 2016. At a distance of only 55 million miles, Mars outshines every star in the night sky (it is slightly brighter than Sirius) and draws attention to itself with its distinctive red color. Plus, it looks great through a backyard telescope:

Peter Garbett of Sharnbrook, UK, took this picture a few nights ago using his 14-inch Celestron. "It was so cold outside my finger froze to the telescope tube," he says, "but it was worth it!"

Even colder than England is the Martian north pole. Temperature: -230 F. The blue polar clouds in Garbett's photo are a result of this low temperature; they are filled with tiny crystals of water and carbon dioxide ice that scatter blue wavelengths of sunlight. This "North Polar Hood" is one of the most striking aspects of Mars in the eyepiece. Ready to look? Train your optics on the bright red "star" rising in the east after sunset: sky map.

more images: from Dan Petersen of Racine, Wisconsin; from Sean Walker of Chester, New Hampshire; from Wah! of Hung Hom, Hong Kong; from Richard Smedley of Broken Arrow, Oklahoma; from Sadegh Ghomizadeh of Tehran, Iran; from Geoff Chester of Alexandria, Virginia.

GREAT GEMINIDS: The reports are in and the verdict is ... the Geminids were a blast after all. The shower peaked on Dec. 14th and 15th with as many as 140 meteors per hour. Many were fireballs. This Geminid near Warsaw, Poland, lit up the night like a full Moon:

Click to view the complete 2.8 MB movie

"The meteoroid fragmented into 4 pieces and observers heard a sonic boom similar to distant thunder," says Jarosław Dygos of the Polish Fireball Network whose TV camera recorded the explosion. "Look at the halo around the fireball," he points out. That was caused by meteor-light passing through ice crystals in the clouds--"beautiful!"

Just as the shower was dying down on Dec. 16th, a strange sound echoed from the loudspeaker of Thomas Ashcraft's radio telescope in New Mexico. "A bright fireball was flying overhead," he says. The sound was a distant TV transmitter reflected from the fireball's ionized trail. He combined footage of the fireball with a recording of the echo to produce this movie. Don't forget to turn up the volume.

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 17, 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 XH16
Dec. 24
8.1 LD
565 m
2007 TU24
Jan. 29
1.4 LD
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, -- This site is penned daily by Dr. Tony Phillips.
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