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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 332.2 km/sec
density: 3.7 protons/cm3
explanation | more data
Updated: Today at 2219 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Sep18
24-hr: A0
0935 UT Sep18
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 18 Sep 07
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 17 Sep 2007
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= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Updated: 2007 Sep 18 2153 UT
Interplanetary Mag. Field
Btotal: 2.0 nT
Bz: 0.2 nT south
explanation | more data
Updated: Today at 2220 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on Sept. 21st or 22nd. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2007 Sep 18 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 Sep 18 2203 UTC
0-24 hr
24-48 hr
10 %
10 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
10 %
10 %
01 %
01 %
What's up in Space
September 18, 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. .

HANDS ON THE SUN: The 7th annual HOTS conference for solar observers and photographers is taking place this year in Irvine, California, Oct. 4th-6th. This is a great opportunity for novices to learn the art of solar photography from masters such as Gary Palmer and Paul Hyndman. In addition to hands-on training and the ever-popular Fiesta Under the Stars, the conference features a Mt. Wilson telescope tour led by comet hunter Dr. David Levy and a keynote speech ("Sizing Up the Next Solar Cycle") by's Dr. Tony Phillips. Join us if you can!

PERUVIAN METEORITE: There is much discussion on the Internet today concerning a reported meteorite impact in Peru which may have gouged a 10- to 30-meter wide crater. Bad-smelling fumes from the crater are said to have sickened dozens and perhaps hundreds of people in a nearby village. Could this be true? (continued below)

There is indeed a hole in the ground in Peru, pictured above, and by all accounts it smells bad, but it is not likely of cosmic origin. In order to blast a 30-meter crater, a meteorite would have to hit the ground with about as much energy as 1 kiloton of TNT--akin to a tactical nuclear weapon. This would leave a clear signal in worldwide seismic and infrasound records, but so far no such signals are being reported by authorities.

In short, we remain unconvinced. Stay tuned for updates.

TRILOBITES INVADE THE SUN: Last week in Boulder, Colorado, scientists converged on the "Living With A Star" workshop to share the latest research in solar physics. At one point, nearly 200 participants sat slack-jawed as they watched a new movie recorded by Japan's Hinode spacecraft showing a sunspot emerging from the depths of the sun:

Click to launch the 19 MB movie.

According to some observers, the emerging spot resembled nothing less than a swimming planet-sized trilobite. The unexpected form and behavior of the sunspot is both a challenge and delight to researchers working to understand solar activity. Get the full story from Science@NASA.

September 2007 Aurora Gallery
[August 2007 Aurora Gallery] [Aurora Alerts]

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 September 18, 2007 there were 886 potentially hazardous asteroids.
Sept. 2007 Earth-asteroid encounters:
Miss Distance
2007 RF1
Sep. 2
8.5 LD
26 m
2007 RS1
Sep. 5
0.2 LD
3 m
2007 RJ1
Sep. 16
2.5 LD
40 m
2007 RC20
Sep. 20
5.1 LD
22 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 Environment 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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