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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 333.2 km/sec
density: 10.7 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Jul20
24-hr: A0
2340 UT Jul20
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 20 July 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 19 July 2009

Spotless Days
Current Stretch: 9 days
2009 total: 151 days (76%)
Since 2004: 662 days
Typical Solar Min: 485 days
explanation | more info
Updated 19 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: 5.2 nT
Bz: 1.1 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on July 22nd or 23rd. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Jul 20 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 20 2201 UTC
0-24 hr
24-48 hr
25 %
10 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
35 %
15 %
05 %
05 %
01 %
01 %
What's up in Space
July 20, 2009

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


SOLAR ACTIVITY: A big show is underway on the sun today. Two massive prominences are dancing along the northwestern limb with such allure that the Solar and Heliospheric Observatory (SOHO) has boosted its frame-rate to capture the motions. Stay tuned for movies, and meanwhile, keep an eye on the sun.

POSSIBLE IMPACT EVENT ON JUPITER: Did something just hit Jupiter? On July 19th, a black "scar" appeared in Jupiter's clouds similar to the Shoemaker-Levy 9 impacts of 1994. Veteran Jupiter observer Anthony Wesley photographed the feature from his observatory in Murrumbateman, Australia:

"The jet-black mark is near Jupiter's south pole (south is up in the image)," says Wesley. "I have imagery of that same location from two nights earlier without the impact mark, so this is a very recent event. The material has already begun to spread out in a fan shape on one side, and should be rapidly pulled apart by the fast jetstream winds. I recorded a lot of footage, and will be generating more images and a rotation animation soon."

Amateur astronomers around the world should train their telescopes on Jupiter tonight to monitor the progress of this possible impact event: sky map. Stay tuned for more images and updates.

more images: from Ian Sharp of Ham, West Sussex, England, UK; from David Kolb of Lawrence, Kansas; from David Storey of Isle of Man, Great Britain; from Frank Ryan Jr of Shannon, Ireland; from Russell Hawker of Eastleigh, Hampshire; from Lars Zielke of Tvis, Denmark

NOCTILUCENT CLOUDS: Noctilucent clouds are brightening again over Europe. "This morning we had a fantastic display--possibly the best of the year so far," reports John Houghton of Leicester UK. He snapped this photo using a Nikon D700:

The display was vivid electric-blue and included some unusual forms. "They reminded me of a great whale swimming across the sky," remarks eyewitness Peter Vasey of Hexham UK.

When a similar display materialized over Europe last week, the clouds quicky spread across the Atlantic, appearing in the USA as far south as Utah, Colorado, northern California and Nevada. Could it happen again tonight? Browse the photo gallery for observing tips:

UPDATED: 2009 Noctilucent Photo Gallery
[previous years: 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 July 20, 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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