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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: 307.6 km/sec
density: 11.0 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Jul21
24-hr: A0
2340 UT Jul21
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 21 July 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 20 July 2009

Spotless Days
Current Stretch: 10 days
2009 total: 152 days (76%)
Since 2004: 663 days
Typical Solar Min: 485 days
explanation | more info
Updated 20 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= 2
quiet
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Interplanetary Mag. Field
Btotal: 7.5 nT
Bz: 6 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about July 23rd. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2009 Jul 21 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 21 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
10 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
What's up in Space
July 21, 2009

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

 

SOLAR ECLIPSE--SOON! The longest solar eclipse of the 21st century is about to begin. It starts just hours from now at 9 p.m. EDT on July 21st (0100 UT on July 22nd). The path of totality crosses many major cities in India and China, setting the stage for possibly the best-observed eclipse in history. Stay tuned for photos! [full story] [webcasts] [eclipse maps]

COSMIC COLLISION: Evidence is mounting that something hit Jupiter no more than a few days ago. The impact site was discovered by amateur astronomer Anthony Wesley on July 19th. Using a 14.5-inch telescope at his backyard observatory in Murrumbateman, Australia, he photographed a dark scar in Jupiter's clouds. NASA astronomers rushed to confirm the find, and with this photo from the Infrared Telescope Facility in Hawaii, they did:

The bright spot is near-infrared sunlight reflected from particulate matter floating through the top of Jupiter's atmosphere. These particulates are likely debris from something that hit the planet and exploded. "This has all the hallmarks of the comet Shoemaker-Levy 9 impacts of 1994," says Leigh Fletcher of JPL who gathered the infrared data along with colleague Glenn Orton.

If the impact hypothesis is indeed correct, the "scar" should become spread out by jet streams in the days ahead. Amateur astronomers can monitor events using mid-sized backyard telescopes: sky map. The spot is located near Jupiter's System II longitude 210°. For the predicted times when it will cross the planet's central meridian, add 2 hours and 6 minutes to Sky and Telescope's predicted transit times for Jupiter's Great Red Spot.

UPDATE: On July 20th, Dennis Simmons of Brisbane Australia recorded a 75-minute movie of the impact site. Click on the image to launch a gif animation:


Play the movie

"It is quite fascinating to observe the white spot (a Mars-sized storm) appearing to overtake the impact scar," notes Simmons. "To make the movie I used a 7-inch Takahashi Mewlon 180 telescope with a Vixen x2 Barlow and a DBK21AF04 ccd camera."

more images: from Antonello Medugno of Italy; from Robert Lunsford of Chula Vista, California; from Jeremy Perez of Flagstaff, Arizona; from Theo Ramakers of Social Circle, Georgia; from Anthony Wesley of Murrumbateman, Australia; from Ian Sharp of Ham, West Sussex, England, UK; from David Kolb of Lawrence, Kansas; from David Storey of Isle of Man, Great Britain; from Frank Ryan Jr of Shannon, Ireland; from Russell Hawker of Eastleigh, Hampshire; from Lars Zielke of Tvis, Denmark;


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 21, 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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