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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 375.4 km/sec
density: 0.6 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Mar17
24-hr: A0
1410 UT Mar17
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 17 Mar 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 17 Mar. 2009
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: 1.5 nT
Bz: 1.3 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about March 20th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Mar 17 2201 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: 2009 Mar 17 2201 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
10 %
10 %
01 %
01 %
01 %
01 %
What's up in Space
March 17, 2009

AURORA ALERT: Did you sleep through the Northern Lights? Next time get a wake-up call: Spaceweather PHONE.


ASTEROID FLYBY TONIGHT: Newly-discovered asteroid 2009 FH is flying past Earth tonight only 85,000 km away. That's about twice the altitude of a geosynchronous communications satellite. Advanced amateur astronomers in North America can photograph the 20-meter-wide space rock racing through the constellation Gemini after sunset on March 17th. It should be about as bright as a 14th magnitude star. [ephemeris] [3D orbit]

A LITTLE SOLAR ACTIVITY: The sun is in the pits of the deepest solar minimum in almost 100 years. At such a calm time, even a little solar activity is remarkable. Here it is. SOHO recorded the movie on March 16th; it shows a minor CME billowing away from the sun's eastern limb. When the sun is active, we see several such CMEs on a daily basis. Now, the rate is about one per month. That's very little solar activity.

RAINBOW PLANET: Something special is happening to Venus. The brightest of all planets is hanging low in the western sky at sunset, and if you look at it with a backyard telescope, you'll see that it is a slender 4% crescent. But that's not the special part.

What's special is, Venus looks like a rainbow:

Sadegh Ghomizadeh took the picture from Tehran, Iran, on March 10th. It shows the view through his 11-inch Celestron. "The seeing was poor, but Venus was still bright and beautiful," he says.

Venus resembles a rainbow because Earth's atmosphere acts like a prism. When Venus is near the horizon, refraction separates the red crescent from the blue. The crescent is so thin, the splitting of colors is obvious. Later this month, Venus will disappear into the glare of the spring sun, so catch the rainbow planet while you can!

more images: from P-M Hedén of Vallentuna, Sweden; from Alan Simpson of Renfrew, Scotland; from Frederic Caron of Victoriaville, Qc, Canada

AURORA BLARNEYALIS: Green auroras over Greenland? It must be St. Patrick's Day. The celebration began last night with this display over Nuuk:

"They were not the most powerful auroras," says photographer Thomas Bojer Eltorpbut, "but it was such a beautiful display." He took the picture by opening the shutter of his Nikon D3 for 90 seconds at ISO 1600.

More green is in the offing. A solar wind stream is heading for Earth, and it could spark even stronger geomagnetic activity when arrives on or about March 20th. Arctic sky watchers should be alert for auroras on the first night of Spring.

Happy St. Patrick's Day!

March 2009 Aurora Gallery
[previous Marches: 2008, 2007, 2006, 2005, 2004, 2003, 2002]

Comet Lulin Photo Gallery
[Comet Hunter Telescope: review] [Comet Lulin finder chart]

Explore the Sunspot Cycle

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 March 17, 2009 there were 1043 potentially hazardous asteroids.
March 2009 Earth-asteroid encounters:
Miss Distance
2009 DS43
Mar. 1
6.9 LD
32 m
2009 DD45
Mar. 2
0.2 LD
35 m
2009 DN4
Mar. 3
8.1 LD
27 m
2009 EA
Mar. 4
7.4 LD
24 m
2009 EW
Mar. 6
0.9 LD
23 m
161989 Cacus
Mar. 7
70.5 LD
1.7 km
2009 EH1
Mar. 8
1.6 LD
12 m
2009 ET
Mar. 9
9.5 LD
15 m
2009 DV43
Mar. 10
8.5 LD
80 m
2009 EU
Mar. 11
3.5 LD
21 m
1998 OR2
Mar. 12
69.8 LD
3.3 km
2009 DR3
Mar. 14
7.2 LD
225 m
2009 FH
Mar. 18
0.2 LD
21 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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