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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 312.5 km/sec
density: 1.9 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Jul17
24-hr: A0
0635 UT Jul17
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 17 July 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 16 July 2009

Spotless Days
Current Stretch: 6 days
2009 total: 148 days (76%)
Since 2004: 659 days
Typical Solar Min: 485 days
explanation | more info
Updated 16 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= 1
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 2.4 nT
Bz: 0.1 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about July 21. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Jul 17 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 17 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 17, 2009

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


APOLLO LANDING SITES PHOTOGRAPHED: NASA's Lunar Reconnaissance Orbiter has returned its first imagery of Apollo landing sites. The pictures show lunar module descent stages, scientific instruments and even 40-year-old foot trails made by astronauts walking across the dusty lunar surface: full story.

NLCs INVADE THE USA: On July 15th, a wave of intense noctilucent clouds (NLCs) descended over the continental United States. "They were bright enough to see over the city lights of Seattle," reports Bob Harrington, who has been watching the skies of Washington for 46 years, and "this is only the third time I have seen a display like this."

"I was able to eyeball these clouds all the way from the horizon to the zenith," he says. "It was very pretty! ."

Similar reports have poured in from Colorado, Oregon, Montana, Nebraska, Idaho, the Dakotas and northern California. These sightings are significant because they come from places so far south. When noctilucent clouds first appeared in the late 19th century, they were confined to latitudes above 50o N (usually far above). The latitude of the Colorado sighting is only 39° N. No one knows why NLCs are expanding their range; it's one of many unanswered questions about the mysterious clouds.

Sky watchers at all latitudes should be alert for NLCs. Observing tips may be found in the photo gallery:

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

MAN-MADE NLCs: On July 15th, Nature provided a grand display of noctilucent clouds stretching from Scandinavia to Colorado. At the same time, NASA provided a miniature display of its own over Florida:

"We saw some brilliant night-shining clouds here in Florida," reports Martin Zloty of Land O'Lakes, just north of Tampa. "They appeared about three hours after space shuttle Endeavour launched on its mission to the International Space Station."

Indeed, Endeavour was the source of the clouds. The space shuttle's hydrogen-burning main engines spew tons of water vapor into the atmosphere during their ascent to space. When the shuttle reaches an altitude of 60 to 70 km, the water vapor turns into super-tiny ice crystals that glow electric blue when illuminated by the setting sun. It looks much like a noctilucent cloud and in a sense it is, created by man rather than Nature. A movie from researchers at Hampton University shows the process in action.

more images: from Fendell Pillsbury of Sarasota, Florida

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 17, 2009 there were 1065 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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