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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: 349.3 km/sec
density: 6.5 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Aug11
24-hr: A0
2340 UT Aug11
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 07 Aug 09
The sun is blank--no sunspots. Credit: SOHO/MDI

NOTE:
The Solar and Heliospheric Observatory is passing through a telemetry keyhole. Daily sun images will be intermittently delayed until routine contact is established later this week.
Sunspot number: 0
What is the sunspot number?
Updated 10 Aug 2009

Spotless Days
Current Stretch: 31 days
2009 total: 173 days (78%)
Since 2004: 684 days
Typical Solar Min: 485 days
explanation | more info
Updated 10 Aug 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: 3.2 nT
Bz: 1.6 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
There are no coronal holes on the Earth-facing side of the sun. Credit: Hinode X-ray Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2009 Aug 11 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 Aug 11 2201 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
02 %
02 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
What's up in Space
August 11, 2009

THERE'S AN APP FOR THAT: You can now experience the Perseid meteor shower on your iPhone. It's cloud-proof! Learn more and give it a try.

 

SPACEWEATHER RADIO: The US Air Force Space Surveillance Radar is scanning the skies over North America. When a Perseid meteor passes overhead--"ping"--there is an echo. Tune into Spaceweather Radio for a live audio feed from the radar facility.

PERSEID UPDATE: The Perseid meteor shower is about to peak. The show begins after sunset on Tuesday, August 11th, and continues until dawn on Wednesday, August 12th. During the long night, sky watchers could see dozens of meteors per hour. (continued below)

A time of particular interest is 0800 UT (1 am PDT) on August 12th. That's when Earth is expected to pass through a denser-than-usual filament of dust from the shower's parent Comet Swift-Tuttle. For an hour or so, rates could surge to 200 per hour. Bright moonlight will blot out many of those Perseids, but even a fraction of 200 is a good show. Observing tips may be found in the Science@NASA story "The Perseids are Coming."

UPDATED: 2009 Perseid Photo Gallery
[Previous Perseids: 2008, 2007, 2006, 2005, 2004, 2001]

TOP SECRET: Not every light that streaks across the night sky is a Perseid. Some of them are spy satellites. Here's one gliding over Maghaberry, Northern Ireland, on August 10th:

"It was Lacrosse 3," reports photographer John McConnell. "Spaceweather's Simple Satellite Tracker predicted a flyby and there it was."

Lacrosse 3 is a top-secret yet easily observed US National Reconnaissance Office spy satellite. It often attracts attention when sunlight glints brightly from its solar panels, rumored to span 45 meters from tip to tip. The solar arrays power a synthetic aperture radar, which can image Earth's surface with meter-resolution even through clouds. Some web sites claim that the radar can also sense objects underground, but that's just speculation.

"I couldn't mistake Lacrosse 3 because it was so bright," says McConnell. "This is even better than Perseids!"


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


July 2009 Aurora Gallery
[previous Julys: 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 August 11, 2009 there were 1067 potentially hazardous asteroids.
August 2009 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2009 MC9
Aug. 7
70.3 LD
16
1.2 km
2009 OF
Aug. 8
15.4 LD
18
220 m
2007 RQ17
Aug. 9
8.4 LD
17
130 m
2000 LC16
Aug. 17
75.6 LD
14
2.0 km
2006 SV19
Aug. 21
59.2 LD
16
1.3 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 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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