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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 472.3 km/sec
density: 0.7 protons/cm3
explanation | more data
Updated: Today at 2242 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Dec23
24-hr: A0
2245 UT Dec23
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 23 Dec 07
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 23 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= 0 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:

Switch to: Europe, USA, New Zealand, Antarctica
Updated: 2007 Dec 23 2101 UT
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 3.4 nT
Bz: 1.0 nT north
explanation | more data
Updated: Today at 2247 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: 2007 Dec 23 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 23 2203 UTC
0-24 hr
24-48 hr
15 %
15 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
15 %
05 %
05 %
01 %
01 %

What's up in Space
December 23, 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.

MOON AND MARS: Please do not miss this: Tonight, just after sunset, the full Moon and Mars will rise in the east less than 2o apart. These are the two brightest objects in the evening sky; hanging so close together, they'll look absolutely dynamite. Bundle up and look: sky map.

URSID OUTBURST: "Initial reports from observers in Europe seem to confirm that an outburst of Ursids happened close to the predicted peak time," says forecaster Peter Jenniskens of the SETI Institute. "First reports put the rate around ZHR = 25/hr (predicted was 40 - 70/hr). The peak time may have been around 21:15 UTC (predicted 20.0 - 22.2 h UTC) on Dec. 22nd."

This bright Ursid flew overhead near Santa Cruz, California:

"This meteor appeared right in the center of the field of view," report photographers Brian Murahashi and Jim Albers. "Wow! There were bright pink and violet colors, multiple flares, and a persistent train, which we captured on our all sky camera."

The intensity and timing of the flurry is in good accord with predictions that Earth would run into a stream of dust from Comet 8P/Tuttle on Dec. 22nd. Now that the meteor shower is over, attention turns to the comet itself. After a 13.6 year absence, 8P/Tuttle is once again traveling through the inner solar system. At closest approach to Earth on Jan. 1st and 2nd, 2008, the comet, will brighten to 5th or 6th magnitude--a fine target for backyard telescopes and digital cameras.

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

SOLSTICE SUNRISE: Yesterday was the first day of summer in Brazil. Photographer Alexandre Amorim was up at dawn to catch the season's first sunrise on Santa Catarina's Island:

"The solstice sun was sandwiched between the uprights of our local dolmen," says Amorim. "With the Atlantic Ocean to the east, it is possible that ancient inhabitants of Santa Catarina's Island used this [rock tower] to mark the summer solstice. Today, the dolmen is useful to teach how the sun moves back and forth along the horizon in different seasons of the year."

more solstice sun photos: from Danilo Pivato of Rome, Italy; from Tom Soetaert of Lawrence, Kansas; from Doug Zubenel of Johnson County, Kansas; from Ivar Marthinusen of Skedsmokorset, Norway; from Cai-Uso Wohler of Bispingen, Germany.

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 23, 2007 there were 913 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
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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