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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 610.7 km/sec
density: 1.5 protons/cm3
explanation | more data
Updated: Today at 2244 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Sep24
24-hr: A0
0635 UT Sep24
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 24 Sep 07
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 22 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= 4
explanation | more data
Current Auroral Oval:

Switch to: Europe, USA, New Zealand, Antarctica
Updated: 2007 Sep 24 2151 UT
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 2.8 nT
Bz: 1.5 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 or about Sept. 27th. Credit: SOHO Extreme UV Telescope.
NOAA Forecasts
Updated at: 2007 Sep 24 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 24 2203 UTC
0-24 hr
24-48 hr
15 %
10 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
10 %
05 %
05 %
01 %
01 %

What's up in Space
September 24, 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. .

ARSENIC FUMES: What made Peruvian villagers sick on Sept 16th when a meteorite struck near Lake Titicaca? Arsenic fumes. According to Peru's Mining, Metallurgy, and Geology Institute, the crash site coincides with a natural underground deposit of arsenic. Visitors to the crater inhaled fumes resulting in headaches and nausea. Sensational reports attributing the crater and the illnesses to a downed radioactive spy satellite were unfounded.

DRIVING INTO THE EQUINOX: Ouch! Do you find yourself squinting more than normal while driving to work in the morning? Blame the equinox. At this time of year, the sun rises and sets almost due east and west--the same direction as almost half of all roadways. This morning's photo from Richard Pirko of Youngstown, Ohio, illustrates the effect:

In the full-sized image, "Venus is visible between the phone wires, above and to the right of the Sun," points out Pirko. "A small jet trail is on the left."

Autumn is also the season for auroras. Browse the gallery below to enjoy some of the extraordinary lights that have appeared in recent days over the polar circle.

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

SHADOWS OF VENUS: Venus is so bright, it actually casts shadows. You just have to stare a while to see them. This 6-minute exposure at ISO 800 comes from Tenho Tuomi of Lucky Lake, Saskatchewan, Canada:

"Venus projected the shadow of my telescope on the house wall," he marvels.

To experience your own Venus shadow, chose a dark place--very dark--away from city lights. Go there just before dawn. No sky map is necessary to find Venus glaring in the east. Let your eyes fully dark-adapt as the silvery light of the Morning Star illuminates your face. Now turn around. What do you see?

BONUS: Got a backyard telescope? Point it at Venus. Like the Moon, Venus has phases, and at the moment it is a beautifully slender crescent. Take a look!

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 24, 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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