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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 422.7 km/sec
density: 6.1 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Jul27
24-hr: A0
0315 UT Jul27
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 26 Jul 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 25 July 2008
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= 2 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 7.0 nT
Bz: 2.6 nT north
explanation | more data
Updated: Today at 2246 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2008 Jul 27 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: 2008 Jul 27 2203 UTC
0-24 hr
24-48 hr
10 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
10 %
01 %
01 %
01 %
01 %
What's up in Space
July 27, 2008
AURORA ALERTS: Did you miss the Northern Lights of July 12th? Next time get a wake-up call from Space Weather PHONE.  

PLASMA BULLETS SPARK NORTHERN LIGHTS: Researchers have discovered what powers brilliant outbursts of Northern Lights: gigantic plasma bullets launched toward Earth by explosions 1/3rd of the way to the Moon. Get the full story from Science@NASA.

LAMPYRIDID METEOR: Most meteors burn a straight path through Earth's atmosphere, but last week Doug Zubenel of De Soto, Kansas, photographed one that didn't--a lovely curving Lampyridid:

"It's a firefly," says Zubenel. "While I was photographing the Big Dipper over our neighbor's oak trees, a bright green one left its serendipitous signature upon the CMOS sensor of my Canon Rebel XTi."

Fireflies are nocturnal members of the beetle family Lampyridae. They meander curvaceously through the atmosphere producing their cold, green light via a biochemical reaction between oxygen and luciferin. Genuine meteors, on the other hand, produce their light by brute kinetic force. They race through the atmosphere at speeds exceeding 100,000 mph, heating the air to temperatures of 5000o C or more.

Watch out Lampyridids, the real thing is coming. Earth is approaching a stream of debris from Comet Swift-Tuttle, the source of the annual Perseid meteor shower. First contact with the stream comes in the waning days of July. At first, only a few meteors per hour will flit across the night sky, but as Earth moves progressively deeper into the stream, the shower will intensify. Forecasters expect the Perseids to peak on Tuesday, August 12th, with a flurry of dozens and perhaps hundreds of shooting stars, straight-shooters all. Science@NASA has the full story.

RINGS AROUND THE SUN: The next time you see a cloud approaching the sun, duck into the shadows and watch what happens. Monika Landy-Gyebnar of Veszprem, Hungary, followed these instructions, and here is her report:

"Coming home from work I saw a nice altocumulus cloud drifting toward the sun. So I only had to find something to shade the sun and wait.... Soon, four rings appeared; they had wonderfully bright colors and completely encircled the sun." A 1/4000 second exposure at ISO 100 produced this image:

This rainbow-colored apparition is not a rainbow, but "a corona," says atmospheric optics expert Les Cowley. "Coronas are much smaller than rainbows and are hard to see unless you shield the sun. They are the diffraction pattern produced when light waves bounce off small cloud droplets. One ring is usual, four are a rarity!"

Other things you can see from the shadows: iridescence, ice halos and sundogs. The view is great and, on a hot summer day, it's a cool place to be.

more images: from Kyle Rohr at Crater Lake, Oregon; from Emma Herranen of Tampere, Finland; from Bob King of Duluth, Minnesota; from Yasmin Angelique Walter of Dreieich, Germany; from Austin Taylor of Scalloway, Shetland Islands, UK; from Doug Zubenel of Johnson Co., Kansas

2008 Noctilucent Cloud Gallery
[Strange Clouds] [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 July 27, 2008 , there were 962 potentially hazardous asteroids.
July 2008 Earth-asteroid encounters:
Miss Distance
2003 YE45
July 13
16.5 LD
1.4 km
2008 BT18
July 14
5.9 LD
1.0 km
2003 LC5
July 15
62 LD
1.4 km
2008 NP3
July 17
6.8 LD
85 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...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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