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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: 290.4 km/sec
density: 2.8 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Jul20
24-hr: A0
1255 UT Jul20
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 20 Jul 08
Tiny sunspot 1000 is fading away, leaving the sun once again blank. Credit: SOHO/MDI
Sunspot number: 12
What is the sunspot number?
Updated 19 July 2008
Far side of the Sun:
This holographic image reveals no large sunspots on the far side of the sun. Yesterday's tentative detection of a far side spot is not confirmed. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 1
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: 3.8 nT
Bz: 2 nT south
explanation | more data
Updated: Today at 2246 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on July 22nd or 23rd. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2008 Jul 20 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 20 2203 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
20 %
MINOR
05 %
10 %
SEVERE
01 %
01 %
What's up in Space
July 20, 2008
AURORA ALERTS: Did you miss the Northern Lights of July 12th? Next time get a wake-up call from Space Weather PHONE.  

SPACE STATION FLYBYS: Sky watchers in Europe and North America are in for a treat. For the next few days, the International Space Station will be orbiting over the two continents, appearing brightly in the morning and evening sky. Check the Simple Satellite Tracker to find out when to look.

PERSIAN CLOUDS: Noctilucent clouds (NLCs) are supposed to be a high-latitude phenomenon, most often seen in Canada, Russia and northern Europe. On July 19th the electric-blue clouds crept south, all the way to Iran:

"I took this picture from Mt. Sabalan, a 15,784 ft extinct volcano in northwestern Iran," says Siamak Sabet. "It is the third highest peak in our extremely mountainous country."

When noctilucent clouds first appeared in the late 19th century, they were confined to latitudes above 50o N. Mt Salaban is located at 38o N, far below the old threshold. Just last week, NLCs were sighted in Turkey at 40o N and in recent years they have appeared at least as far south in the United States as Colorado and Utah, also around 40o N.

Why are NLCs spreading south? That is an unsolved mystery of these puzzling clouds. Some researchers believe it is a telltale sign of climate change, but this remains controversial. One thing is certain: Sky watchers at all latitudes should be alert for for NLCs. Observing tips may be found in the photo gallery:

2008 Noctilucent Cloud Gallery
[Strange Clouds] [Sky Cameras]

SHREDDED STORM: On July 1st, a Mars-sized storm on Jupiter called the "Little Red Spot" (LRS) ran into two of its siblings: the Great Red Spot and Oval BA. Caught between the two larger storms, the Little Red Spot was torn apart. These before and after shots come from the Hubble Space Telescope:

The gray arrow in the July 8th image points out the remains of the LRS. One can only imagine the turmoil and shredding action that took place when the LRS tried to squeeze itself between the other two storms, because Hubble wasn't looking when it happened; the great telescope was scheduled to observe something else that day.

With greater flexibility at their home observatories, a number of skilled amateur astronomers did record the collision using backyard telescopes. Their images show the LRS being torn apart and then, possibly, reforming itself for a second collision with the Great Red Spot later this month. Click here for more information.

       
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 20, 2008 , there were 962 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
2008 NP3
July 17
6.8 LD
18
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, SpaceWeather.com -- This site is penned daily by Dr. Tony Phillips.
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