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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 376.1 km/sec
density: 4.6 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: C2
2230 UT Jan17
24-hr: C2
2230 UT Jan17
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 17 Jan. 10
Sunspot 1040 is a member of new Solar Cycle 24. Image credit: SOHO/MDI
Sunspot number: 24
What is the sunspot number?
Updated 16 Jan 2010

Spotless Days
Current Stretch: 0 days
2010 total: 1 day (6%)
2009 total: 260 days (71%)
Since 2004: 772 days
Typical Solar Min: 485 days
explanation | more info
Updated 16 Jan 2010

The Radio Sun
10.7 cm flux: 84 sfu
explanation | more data
Updated 16 Jan 2010

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= 0 quiet
24-hr max: Kp= 1
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 4.1 nT
Bz: 1.7 nT north
explanation | more data
Updated: Today at 2345 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about Jan. 19th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2010 Jan 17 2201 UTC
0-24 hr
24-48 hr
10 %
15 %
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: 2010 Jan 17 2201 UTC
0-24 hr
24-48 hr
10 %
15 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
20 %
01 %
01 %
01 %
01 %
What's up in Space
January 17, 2010

SATELLITE FLYBYS APP: Turn your iPhone or iPod into a field-tested satellite tracker! presents the Satellite Flybys app.


SUNSET CONJUNCTION: When the sun goes down tonight, step outside and look southwest. Jupiter and the 6% crescent Moon are having an eye-catching close encounter. Catch them if you can before the sky fades completely black. A bright conjunction framed by twilight blue is an especially beautiful sight. [sky map]

RING OF FIRE: Last Friday when the Moon passed in front of the sun, the lunar diameter was a little too small to completely cover the star behind it. The mismatch produced a lovely ring of fire:

"I took this picture from the shore of Weishan Lake in the Shandong Province of China," says Xiang Zhan. "We had some clouds, but fortunately the sun was able to shine through the veil. The golden ring was very beautiful over the frozen lake below."

The Moon was so small because it was near the far point of its elliptical orbit around Earth. It was, in other words, an "apogee Moon" about 10% too small for totality. The diminished diameter did not, however, diminish the beauty of the event. Browse the gallery for proof:

UPDATED: Solar Eclipse Photo Gallery
[World Map of Eclipse Sightings]

A BURST OF NORTHERN LIGHTS: On Jan. 15th, a burst of Northern Lights startled observers around the Arctic Circle. "The sky exploded over my head!" reports Øystein Lunde Ingvaldsen, who sends this picture from Bø in Vesterålen, Norway:

"The Northern Lights were insane," he says. "To record them, I used a Nikon D300 set at ISO1600 (f/3.5) for a 10 second exposure."

Arctic photographers may wish to take note of those settings, because more auroras are on the way. A solar wind stream is heading toward Earth and it could spark polar geomagnetic storms when it arrives on Jan. 18th or 19th. Be alert for auroras!

The display could intensify even more on Jan. 18th and 19th. That's when a solar wind stream flowing from a coronal hole is expected to reach Earth. High-latitude sky watchers should be alert for Northern Lights.

UPDATED: January Northern Lights Gallery
[previous Januarys: 2009, 2008, 2007, 2005, 2004, 2001]

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 January 17, 2010 there were 1092 potentially hazardous asteroids.
Jan. 2010 Earth-asteroid encounters:
Miss Distance
2010 AL2
Jan. 11
11.5 LD
23 m
24761 Ahau
Jan. 11
70.8 LD
1.4 km
2000 YH66
Jan. 12
69.5 LD
1.1 km
2010 AL30
Jan. 13
0.3 LD
18 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 space weather bureau
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.
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Daily Sunspot Summaries
  from the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
Science Central
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.













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