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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 353.2 km/sec
density: 0.2 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Oct05
24-hr: A1
0305 UT Oct05
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 05 Oct. 09
The sun is blank--no sunspots. Photo credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 04 Oct 2009

Spotless Days
Current Stretch: 3 days
2009 total: 215 days (78%)
Since 2004: 726 days
Typical Solar Min: 485 days
explanation | more info
Updated 04 Oct 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= 0 quiet
24-hr max: Kp= 1
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 2.3 nT
Bz: 1.1 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Oct 05 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 Oct 05 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
October 5, 2009

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


LUNAR IMPACT VIEWER'S GUIDE: On Friday morning, Oct. 9th, you can watch a pair of spacecraft crash into the Moon with your own eyes. The purposeful impacts are the climax of NASA's LCROSS mission to unearth signs of water in lunar soil. Today's story from Science@NASA tells how and where to look.

HARVEST MOONBOWS: This weekend's Harvest Moon mesmerized onlookers with its luminous beauty. In Missouri Valley, Iowa, photographer Mike Hollingshead managed to tear his eyes away for a moment and he discovered an even better show behind his back:

"It was a lunar fogbow," says Hollingshead. "The bright light of the Harvest Moon was shining into a fogbank rising over a recently-harvested field. The resulting fogbow was surprisingly vivid and well-defined." (At the base of the photo, the dark homunculus is the photographer's own moon-shadow pointing east toward the dawn sky where Venus can be seen shining through the mist.)

Fogbows are sometimes called "white rainbows," and that's about right. Both rainbows and fogbows are caused by light reflected from water droplets. When the droplets are large (rain), they act like prisms, spreading the colors wide for easy visibility. When the droplets are small (fog), the prism-action is reduced, and colors are smeared together into a ghostly-white arc.

In Maghera, Northern Ireland, Martin McKenna also looked away from the Harvest Moon and witnessed a true lunar rainbow. "An evening shower moved in and as if by magic a rainbow appeared directly opposite the Moon," he says. "It only lasted for one minute but it was a great sight."

FINDING GROUND ZERO: If you plan to watch this Friday's lunar impacts through a backyard telescope, start practicing now. Pinpointing Cabeus among so many other craters around the lunar south pole isn't easy. David Evans of Coleshill, UK, found the impact site on Oct. 3rd using his Meade 8-inch telescope:

One way to know you've found the right crater: It'll be the one with an fluffy plume on Friday morning, Oct. 9th. Mission scientists expect debris from the double-impact of LCROSS and its booster rocket to rise about 7 kilometers over the rim of Cabeus. There will be two plumes, one from the booster rocket (4:30 am PDT) and another from the LCROSS mothership (4:34 am PDT). Each is expected to linger in sunlight for 60 to 90 seconds before falling back into the shadowy depths of Cabeus. The surface brightness of the plumes should be similar to that of surrounding sunlit terrain.

To help potential observers witness and photograph the impacts, veteran amateur astronomer Kurt Fisher has prepared an excellent "how-to" slideshow. Another good place to find observing tips and to chat with fellow observers is Google's LCROSS observer's group. NASA's Citizen Science Site and welcome all images of this unprecedented experiment. Let's go!

Sept. 2009 Aurora Gallery
[previous Septembers: 2008, 2007, 2006, 2005, 2004, 2002, 2001]

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 October 5, 2009 there were 1079 potentially hazardous asteroids.
Sept. 2009 Earth-asteroid encounters:
Miss Distance
2009 QC35
Sept. 2
2.9 LD
35 m
2009 RY3
Sept. 11
1.9 LD
50 m
2009 RR
Sept. 16
2.8 LD
33 m
2009 RG2
Sept. 21
9.1 LD
31 m
2009 SN103
Sept. 28
1.2 LD
13 m
2009 HD21
Sept. 29
22.9 LD
1.0 km
1998 FW4
Sept. 29
8.6 LD
550 m
2009 SH2
Sept. 30
2.8 LD
49 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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