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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: 539.5 km/sec
density: 2.5 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Jul23
24-hr: A0
2340 UT Jul23
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 23 July 09
A small sunspot is developing near the center of the solar disk. Browse the images below for snapshots. Credit: SOHO/MDI

more images: from Pavol Rapavy of Observatory Rimavska Sobota
Sunspot number: 0
What is the sunspot number?
Updated 22 July 2009

Spotless Days
Current Stretch: 12 days
2009 total: 154 days (76%)
Since 2004: 665 days
Typical Solar Min: 485 days
explanation | more info
Updated 22 July 2009

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= 3
quiet
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Interplanetary Mag. Field
Btotal: 3.1 nT
Bz: 1.2 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2009 Jul 23 2201 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: 2009 Jul 23 2201 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
What's up in Space
July 23, 2009

AURORA ALERT: Did you sleep through the Northern Lights? Next time get a wake-up call: Spaceweather PHONE.

 

JUPITER UPDATE: Four days after it was discovered, the dark mark in Jupiter's cloudtops where an asteroid or comet hit the giant planet is still easy to see through backyard telescopes. Browse these links for recent images: #1, #2, #3, #4, #5, #6.

AURORA SURPRISE: Sometimes the auroras are so bright, you just can't sleep. "I was up all night on July 21st, but it was totally worth it!" says photographer Zoltan Kenwell of Chip Lake, Alberta. This is what kept him awake:

"It was a very impressive show that lasted 4.5 hours!" says Kenwell.

Forecasters did not predict this display. It began on when a seemingly minor solar wind stream hit Earth's magnetic field. The minor hit turned into a not-so-minor display because a crack opened in Earth's magnetic field, allowing solar wind to pour in and fuel the storm. Northern Lights descended as far south as the Dakotas, Montana, Iowa and Wisconsin. The solar wind is still blowing, but the crack has closed, bringing an end to the lights. Until next time, browse the gallery:

UPDATED: July 2009 Aurora Gallery
[previous Julys: 2008, 2007, 2006, 2005, 2004, 2003]

TOTAL SOLAR ECLIPSE: Chasing an eclipse can be a nerve-wracking experience. Just ask Alan Dyer, who on July 21st was sailing through the path of totality in the south Pacific Ocean when clouds began to gather overhead. "The early, partial stages of the eclipse were blocked," says Dyer. "We had to chase into a clear hole to catch this view of totality."

"The sight of the low-hanging Sun in eclipse was spectacular with an impressively large Sun/Moon disk caused by the 'moon illusion' effect," he says. "In the end, we were a happy ship of 300 eclipse chasers!"

UPDATED: July 22nd Eclipse Gallery
[previous eclipses: Jan 26, 2009; Aug. 1, 2008; Mar. 19, 2007]


2009 Noctilucent Photo Gallery
[previous years: 2008, 2007, 2006, 2005, 2004, 2003]


Explore the Sunspot Cycle

       
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 23, 2009 there were 1067 potentially hazardous asteroids.
July 2009 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2009 MM8
July 13
11.4 LD
18
53 m
2008 NP3
July 18
11.8 LD
18
87 m
2006 TU7
July 20
14.2 LD
17
175 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 space weather bureau
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.
STEREO
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Daily Sunspot Summaries
  from the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
Science Central
   
  more links...
   
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