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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 410.2 km/sec
density: 2.5 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A0
1850 UT Jul31
24-hr: A0
1850 UT Jul31
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 29 July 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 30 July 2009

Spotless Days
Current Stretch: 20 days
2009 total: 162 days (77%)
Since 2004: 673 days
Typical Solar Min: 485 days
explanation | more info
Updated 30 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= 3
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 3.0 nT
Bz: 0.3 nT south
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 31 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 31 2201 UTC
0-24 hr
24-48 hr
20 %
05 %
05 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
05 %
10 %
01 %
05 %
01 %
What's up in Space
July 31, 2009

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


ENDEAVOUR HAS LANDED: Space shuttle Endeavour is back on Earth. The shuttle landed at Kennedy Space Center this morning at 10:49 EDT, completing a two week mission to the International Space Station. During their visit to the ISS, the crew installed the porch-like Japanese Exposed Facility. When science experiments need a dose of hard vacuum or radiation, astronauts can now set them "out on the porch" for exposure. The next shuttle launch is scheduled for Aug. 23rd.

CHANGES ON JUPITER: "On July 30th, it was evident that there is rapid evolution of Jupiter's impact debris cloud," reports amateur astronomer Raffaello Lena of Rome, Italy. "It is becoming very elongated." A polar projection shows the extent of the debris:

The changes are caused by turbulence and especially high-altitude winds in Jupiter's atmosphere. Polar winds blowing 25 m/s and faster could stretch the cloud all the way around Jupiter's south pole in the weeks ahead. Whether such a stretched-out cloud will be visible in small telescopes remains to be seen.

Amateur astronomers are encouraged to continue monitoring. 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. [sky map]

more images: from Giovanni Coltro of Pesaro, Italy; from Romulo Liporaci of Maracaibo, Venezuela; from Sid Leach of Scottsdale, Arizona; from Tamas Ladanyi of Bakonykoppany, Hungary; from Efrain Morales Rivera of Aguadilla, Puerto Rico; from Andreas Murner of Lake Chiemsee, Bavaria, Germany; from John Chumack of Dayton, Ohio USA

NOCTILUCENT CLOUDS OVER MONGOLIA: When flying over Mongolia after dark, be sure to look out the window. You might see some noctilucent clouds:

Photo details: Nikon D300, Nikkor 18-200 VR, 1/3s at ISO 1600

"I photographed these NLCs over central Mongolia on July 27th while flying onboard an Air France Boeing 777," reports photographer Radek Grochowski. "It was exciting to see them shining delicately electric-blue against almost black sky. The photo barely shows what you could see with your eyes."

Add Mongolia to the list of unaccustomed places NLCs have been sighted this year. Decades ago, noctilucent clouds were purely a high-latitude phenomenon, but recently they have descended from their arctic habitat to visit California, Nevada, Utah, Colorado, France, Turkey and now Mongolia. No one knows why the mysterious clouds are increasing their range, but they are, so check the gallery for observing tips:

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

July 2009 Aurora Gallery
[previous Julys: 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 31, 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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