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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 332.6 km/sec
density: 6.7 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Aug17
24-hr: A0
2340 UT Aug17
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 17 Aug 09
The sun is blank--no sunspots. Photo credit: Howard Eskildsen, Ocala, Florida
Sunspot number: 0
What is the sunspot number?
Updated 16 Aug 2009

Spotless Days
Current Stretch: 37 days
2009 total: 179 days (79%)
Since 2004: 690 days
Typical Solar Min: 485 days
explanation | more info
Updated 16 Aug 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: 3.3 nT
Bz: 1.7 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 or about Aug. 18th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Aug 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 Aug 17 2201 UTC
0-24 hr
24-48 hr
10 %
30 %
01 %
10 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
40 %
01 %
20 %
01 %
05 %
What's up in Space
August 17, 2009

AURORA ALERT: Did you miss the Northern Lights? In July they descended as far south as Nebraska. Next time get a wake-up call: Spaceweather PHONE.


BEWARE THE MARS HOAX: If you have marked your calendar for August 27th to remind yourself to watch Mars swell to the size of a full Moon, go back and add these words: Mars Hoax! Contrary to a widespread email alert, Mars will not come close to Earth on August 27th and it can never rival the full Moon in the night skies of our planet. Science@NASA has the full story.

BUSY MORNING: Monday began with a flurry of activity in the eastern sky. The Moon and Venus converged for a beautiful close encounter and, for many observers in North America, the International Space Station zipped across the dawn traveling 17,000 mph. Thomas Dorman photographed the action over Horizon City, Texas:


"Wow, what a show!" says Dorman.

Elsewhere, the Moon-Venus conjunction provided a backdrop for rocket launches and other forms of air travel. It was a busy morning, indeed. Did you miss the show? Next time get a "look-up" reminder from Spaceweather PHONE.

more images: from Richard Glenn of Cape Sebastian, OR; from Richard Sass of Cloudcroft, New Mexico; from Chris Peterson of Guffey, Colorado; from Monika Landy-Gyebnar of Veszprem, Hungary; from Robert T. Smith of Stoneville, NC; from Jim Tegerdine of Marysville, Washington; from Danny Ratcliffe of Deception Bay, Australia; from Bill Davis of Albuquerque NM; from Sabawa Jordan of Pocomoke City, MD; from Michael Boschat of Halifax, Nova Scotia; from Shevill Mathers of Hobart, Tasmania;

JUPITER AT OPPOSITION: This month, the sun, Earth and Jupiter are almost perfectly aligned. An astronomer would say "Jupiter is at opposition," because Jupiter and the sun are on opposite sides of the sky. This arrangement has a rare and beautiful effect on Jupiter's moon shadows. Consider the following photo taken Aug. 15th by David Leong of Hong Kong:

"The shadow of Jupiter's moon Io fell almost directly beneath Io, giving the scene a 3D appearance," says Leong. "This was my first time watching a shadow transit at opposition. It was amazing." Even more amazing is the movie. Click here to set the scene in motion.

Another benefit of opposition: Jupiter is as close to Earth as it gets. The giant planet rises in the east at sunset and outshines the stars all night long. Train a backyard telescope on Jupiter to see the Great Red Spot, Jupiter's moons, moon shadows, and debris from a mystery impact spreading around Jupiter's south pole.

more images: from Raffaello Lena of Rome, Italy; from Alan Friedman of Buffalo, NY; from Mike Hood of Kathleen, Georgia;

UPDATED: 2009 Perseid Photo Gallery
[Science@NASA: The Perseids are Coming, Horse Flies and Meteors]

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 August 17, 2009 there were 1067 potentially hazardous asteroids.
August 2009 Earth-asteroid encounters:
Miss Distance
2009 MC9
Aug. 7
70.3 LD
1.2 km
2009 OF
Aug. 8
15.4 LD
220 m
2007 RQ17
Aug. 9
8.4 LD
130 m
2000 LC16
Aug. 17
75.6 LD
2.0 km
2006 SV19
Aug. 21
59.2 LD
1.3 km
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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