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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 623.7 km/sec
density: 2.2 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A2
1810 UT Aug07
24-hr: A2
0155 UT Aug07
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 07 Aug 07
Tiny sunspot 966 poses a threat for B- and C-class solar flares. Credit: SOHO/MDI
Sunspot number: 16
What is the sunspot number?
Updated 06 Aug 2007
Far side of the Sun:
This noisy holographic image reveals a possible large sunspot on the far side of the sun. This should be deemed unreliable until confirmed by tomorrow's map. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 6
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Updated: 2007 Aug 07 2110 UT
Interplanetary Mag. Field
Btotal: 4.0 nT
Bz: 2.0 nT north
explanation | more data
Updated: Today at 2246 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SOHO Extreme Ultraviolet Telescope
NOAA Forecasts
Updated at: 2007 Aug 07 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 Aug 07 2203 UTC
0-24 hr
24-48 hr
20 %
15 %
10 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
25 %
20 %
15 %
10 %
10 %
05 %
What's up in Space
August 7, 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.

COUNTDOWN TO THE PERSEIDS: Earth has entered a stream of debris from Comet Swift-Tuttle and this is causing meteors to flow out of the constellation Perseus. The Perseid meteor rate is low now (< 5 per hour), but it is building to an impressive peak (~100 per hour) due Sunday night, August 12th. Get the full story from Science@NASA.

AURORA WATCH: A high-speed solar wind stream hit Earth on August 6th sparking a moderate geomagnetic storm and auroras bright enough to pierce the twilight in Valkeakoski, Finland:

Photo details: Nikon D200, ISO 200, 2 second exposure.

"The 2007 autumn aurora season has finally begun," says photographer Tom Eklund.

Earth is still inside the solar wind stream, but the storm is subsiding. Bright auroras are unlikely tonight. August 9th is the next night to be alert; that's when another solar wind stream is due to arrive.

more images: from Gilles Boutin of St-Jean-Port-Joli, Quebec, Canada

CRESCENT PLANET: Venus has never looked so good. Too bad she's so difficult to see!

Venus is approaching the sun--only 17 degrees away today--which means the brightest planet in the night sky is no longer in the night sky. "But you can pick it up during the day," says Pete Lawrence of Selsey, UK, who yesterday took this picture of Venus in broad daylight:

Venus has become a vanishingly slender crescent. Because Venus is now located almost directly between Earth and the sun, the nightside of Venus is facing Earth, creating this stunning view.

So how do you find Venus in daylight? First, be very careful. Catching sight of the sun by mistake in binoculars or a telescope can blind you--permanently. Try this: At local noon, stand in the shadow of a tall building. With the sun completely blocked, scan the sky east of the sun for a bright pinprick among the blue. If the air is clear, Venus is visible even to the naked eye. A small telescope reveals the crescent.

more images: from Helmut Groell of Moers, Germany; from Vasilis Wooseas of Greece; from G√ľnther Strauch of Borken, NRW, Germany.

.2007 Noctilucent Cloud Gallery
[Night-Sky Cameras] ["Noctilucent Cloud"--the song]

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 August 7, 2007 there were 875 potentially hazardous asteroids.
July 2007 Earth-asteroid encounters:
Miss Distance
2007 FV42
July 2
53 LD
1.2 km
2007 MB4
July 4
7.6 LD
130 m
2007 DT103
July 29
9.3 LD
550 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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