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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 390.9 km/sec
density: 3.1 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Jul28
24-hr: A0
2340 UT Jul28
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 28 July 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 27 July 2009

Spotless Days
Current Stretch: 17 days
2009 total: 159 days (76%)
Since 2004: 670 days
Typical Solar Min: 485 days
explanation | more info
Updated 27 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= 1 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 3.8 nT
Bz: -0.0 nT
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole could reach Earth on or about July 31st. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Jul 28 2201 UTC
0-24 hr
24-48 hr
01 %
01 %
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 28 2201 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
What's up in Space
July 28, 2009

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


TRIPLE FLYBYS: Space shuttle Endeavour has undocked from the International Space Station in preparation for a July 31st return to Earth. Meanwhile, a Russian supply ship, the Progress 34, is approaching the ISS. This sets the stage for a rare set of triple flybys. People who see the space station in the night sky tonight could witness three spaceships (two bright and one dim) in triangular formation. Check the Simple Satellite Tracker to find out when to look.

SPACE STATION SILHOUETTE: It happened in a split second. On July 26th, the International Space Station (ISS) flew in front of the sun over Orleans, France, where astrophotographer Thierry Legault was waiting. He couldn't see the 0.8s transit with the unaided eye, but his telescope and digital camera captured this image:

Photo details: Canon 5D MkII, Takahashi TOA-150 refractor, Herschel prism, 1/8000s

"The silhouette shows space shuttle Endeavour docked to the ISS," he says. "The shuttle's payload bay arm is visible, too."

Legault has taken many pictures of spaceships passing in front of the sun. When he stands beside the telescope at the moment of transit, listening to the camera click, there is no assurance of a good shot. "I never know if the ship will be visible or not, or if the seeing will give good or bad images. The discovery of the silhouette on the computer screen later is the moment I prefer and is a great pleasure."

The ISS will be transiting the French sun again, perhaps several times, in the weeks ahead, says Legault. Stay tuned for snapshots.

JUPITER'S IMPACT CLOUD EXPANDS: Jupiter's impact cloud is expanding. On July 19th, when it was discovered by amateur astronomer Anthony Wesley, the dark mark near Jupiter's south pole was barely visible in backyard telescopes. Five days later Wesley photographed the impact cloud again and found that it had approximately tripled in size:

High-resolution images from the Hubble Space Telescope reveal what's happening: turbulence and jet streams in Jupiter's atmosphere are causing the cloud to spread out. The vast impact site is now tens of thousands of times wider than the 100m-class comet or asteroid that created it.

The expansion of the cloud makes it easier than ever to see through a backyard telescope: sky map. The cloud 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.

more images: from Mike Hood of Kathleen, Georgia; from Didier Favre of Brétigny-sur-orge, France; from Enzo De Bernardini of Martínez, Buenos Aires, Argentina; from Sadegh Ghomizadeh of Iran Tehran; from David Kolb of Lawrence, Kansas;

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

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

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

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 28, 2009 there were 1067 potentially hazardous asteroids.
July 2009 Earth-asteroid encounters:
Miss Distance
2009 MM8
July 13
11.4 LD
53 m
2008 NP3
July 18
11.8 LD
87 m
2006 TU7
July 20
14.2 LD
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.
  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...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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