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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 441.9 km/sec
density: 7.5 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Aug08
24-hr: A0
2340 UT Aug08
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 07 Aug 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 07 Aug 2009

Spotless Days
Current Stretch: 28 days
2009 total: 170 days (78%)
Since 2004: 681 days
Typical Solar Min: 485 days
explanation | more info
Updated 07 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= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 4.6 nT
Bz: 3.0 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: STEREO-A Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Aug 08 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 08 2201 UTC
0-24 hr
24-48 hr
20 %
20 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
30 %
30 %
10 %
10 %
01 %
01 %
What's up in Space
August 8, 2009

THERE'S AN APP FOR THAT: You can now experience the Perseid meteor shower on your iPhone. It's cloud-proof! Learn more and give it a try.


PERSEID UPDATE: The Perseid meteor rate is holding steady at 20 per hour, according to observers from the International Meteor Organization: data. Most of these meteors are difficult to see, however, because bright moonlight is blotting them out. The situation should improve on peak night, August 11th and 12th, when as many as 200 meteors per hour are expected to dash through waning moonlight. Get the full story from Science@NASA.

JUPITER IMPACT CLOUD: Debris from the July 19th mystery-impact on Jupiter has split into three clouds. The trifurcation is evident in this August 7th image taken by Rick Schrantz using a 10-inch telescope at his backyard observatory in Nicholasville, Kentucky:

Other observers have noticed the same thing. "There appear to be 3 distinct impact scars now, somewhat linear in shape and perhaps larger than previous days," reports Joel Warren of Amarillo, Texas. He took these pictures using an 8-inch telescope.

Jupiter's upper atmosphere is a dynamic place. The cindery impact debris appears to be caught up in a cascade of turbulent swirls and eddies, which is literally ripping the cloud apart. Amateur astronomers can monitor what happens next: The impact 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.

more images: from Mike Salway of Central Coast, NSW Australia; from Raffaello Lena of Rome, Italy; from Alphajuno of League City, Texas; from Mike Hood of Kathleen, Georgia, USA

RADIO PERSEIDS: Awash in moonlight, the Perseid meteor shower is at present not very easy to see. Some observers have given up on looking, choosing instead to monitor the shower by means of radio. This plot from Dave Swan shows how he is counting more than 300 Perseid radio echoes per hour using a Yagi antenna and 55.25 MHz receiver in Bransgore, UK:

In the loudspeaker, each echo sounds like a little "ping." It is the reflection of a distant TV transmitter from the meteor's ionized trail. Forward scatter meteor detection, as this technique is called, is more sensitive than ordinary visual observation. Very small meteoroids are able to create a radio echo without leaving any trace of optical light in the sky. That's why Swan is counting 300 radio Perseids per hour while naked-eye observers are couting no more than about 20. Click here to monitor forward scatter stations around the world.

UPDATED: 2009 Perseid Photo Gallery
[previous Perseids: 2008, 2007, 2006, 2005, 2004, 2001]

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

July 2009 Aurora Gallery
[previous Julys: 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 8, 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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