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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
SPACE WEATHER
Current conditions
Solar wind
speed: 331.6 km/sec
density: 3.9 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Jul04
24-hr: A0
2245 UT Jul04
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 04 Jul 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 03 July 2008
Far side of the Sun:
This holographic image reveals a no sunspots on the far side of the sun. The sunspot group reported yesterday has vanished and was probably digital noise. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 3.4 nT
Bz: 3.1 nT south
explanation | more data
Updated: Today at 2246 UT
Coronal Holes:
There are no coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2008 Jul 04 2203 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
CLASS X
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 04 2203 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
What's up in Space
July 4, 2008
AURORA ALERTS: Did you miss the Northern Lights of June 25th? Next time get a wake-up call from Space Weather PHONE.  

PLANETS ALIGN FOR THE 4th OF JULY: Look beyond the fireworks this weekend. A trio of worlds is converging for a pretty sunset sky show: full story. [Sky maps: July 4, 5, 6] [Photos: #1, #2]

EARTH AT APHELION: Today, you are far from the sun. Earth's orbit around the sun is not a perfect circle, it's an ellipse, and on July 4th, Earth is at the most distant end of the curve. Astronomers call this "aphelion." When we are at aphelion, the sun appears smaller in the sky (by 1.7%) and global solar heating is actually a little less (by 3.5%) than the yearly average. This provides scant relief from northern summer heat, however; click here for reasons why.

photos: from Pete Glastonbury of Avebury, Wiltshire, UK; from Alex Con of Bucharest, Romania; from Enrique Luque Cervigón of Alcalá de Henares, Madrid, Spain.

WEIRD SUNSET: Even at a distance, the sun can amaze. Consider this: "On June 29th, the sun got below the marine layer here in La Jolla, California, and something weird happened," reports Steve Shuey. "I took this picture using my Canon 5D."


Photo details: Canon 5D, 420 mm (300+1.4 tele-converter), f5.6, 1/400 s, ISO 400.

Atmospheric optics expert Les Cowley explains what happened: "The sun’s light is slanting through layers of air at different temperature and being split, bent upwards and downwards to make this weird apparition. A multiple mirage has chopped the sun into at least eight slices. The lowest slice on the sea is actually rising upwards from the waves! The apparently choppy sea is also part of the mirage. Smoke from the Californian fires trapped in the temperature inversion layers has darkened the mirage center."

GRAB THAT ROCK: Put on your 3D glasses and reach out. Can you grab the rock?

It seems so near, but this rock is actually 319 million kilometers away at the feet of the Phoenix Mars lander. Spaceweather reader Stuart Atkinson of Kendal, UK, created the anaglyph by combining right- and left-eye images from Phoenix's stereo camera. "The rock seems to be riddled with holes," he says. "Fascinating!"

Behold the complete scene. To the right is one of the trenches Phoenix has been digging. Next week, after a brief 4th of July holiday, mission scientists will command Phoenix to begin chemical analyses of icy soil scraped from the Snow White trench. This should reveal the sample's salt and mineral content, whether it contains nutrients friendly to life, and something of the ice's history. Was it once a nutrient-rich fluid? Stay tuned for updates.


2008 Noctilucent Photo Gallery
[NLC Tutorial] [Night-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 4, 2008 , there were 960 potentially hazardous asteroids.
July 2008 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2003 YE45
July 13
16.5 LD
15
1.4 km
2008 BT18
July 14
5.9 LD
13
1.0 km
2003 LC5
July 15
62 LD
16
1.4 km
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, SpaceWeather.com -- This site is penned daily by Dr. Tony Phillips.
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