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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 344.0 km/sec
density: 4.5 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Jul30
24-hr: A0
2340 UT Jul30
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 28 July 2009

Spotless Days
Current Stretch: 18 days
2009 total: 160 days (77%)
Since 2004: 671 days
Typical Solar Min: 485 days
explanation | more info
Updated 28 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: 4.8 nT
Bz: 0.5 nT north
explanation | more data
Updated: Today at 2347 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 30 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 30 2201 UTC
0-24 hr
24-48 hr
20 %
20 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
20 %
10 %
10 %
05 %
05 %
What's up in Space
July 30, 2009

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


SPACE WEATHER MICROSATS: Space shuttle Endeavour returns to Earth tomorrow, July 31st, completing a successful construction mission to the ISS, but first there is one more chore to do. Today, the shuttle's crew will release Castor and Pollux, a pair of 19-inch spherical satellites. The twin microsats will circle Earth for approximately one year, working together to reveal how geomagnetic storms degrade the orbits of satellites. NASA has the full story.

CHANGES ON JUPITER: "On July 30, it is 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

LUNAR TRANSITS: Catching a spaceship flying in front of the Moon is a rare trick. Yesterday, Roman Piffl of Bratislava, Slovakia, caught two:

"First, space shuttle Endeavour transited the Moon, followed a hundred seconds later by the International Space Station," says Piffl. Each crossing lasted no more than a fraction of a second, "but we were able to capture them using a DMK21 video camera at 60 fps." Piffl was assisted by fellow astronomers Tomáš Maruška and Miroslav Grnja.

Endeavour and the ISS will be in orbit together for just one more day. Check the Simple Satellite Tracker for last-chance flybys.

more images: from Fox Keri of Marion, Massachusetts; from Todd Hahn of Sugar Land, Texas; from Jonathan Sabin of Ellenton, Florida; from Michael Prokosch of Huntsville, Texas

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 30, 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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