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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 287.9 km/sec
density: 1.9 protons/cm3
explanation | more data
Updated: Today at 2247 UT
X-ray Solar Flares
6-hr max: A0
1845 UT Oct17
24-hr: A3
0110 UT Oct17
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 17 Oct 08
Tiny fading sunspots 1005 and 1006 are both members of Solar Cycle 24. Credit: SOHO/MDI
Sunspot number: 24
What is the sunspot number?
Updated 16 Oct. 2008
Far side of the Sun:
This holographic image reveals one possible sunspot on the far side of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 1.9 nT
Bz: 0.5 nT north
explanation | more data
Updated: Today at 2247 UT
Coronal Holes:
There are no coronal holes on the Earth-facing side of the sun. Credit: Hinode X-ray Telescope.
NOAA Forecasts
Updated at: 2008 Oct 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: 2008 Oct 17 2201 UTC
0-24 hr
24-48 hr
01 %
01 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
01 %
01 %
01 %
01 %
01 %
01 %
What's up in Space
October 17, 2008
BEHOLD THE SUN: Would you like to see fiery prominences and new-cycle sunspots with your own eyes? On sale now: Personal Solar Telescopes.  

A NEW KIND OF PULSAR: NASA's Fermi Gamma-ray Space Telescope has discovered a new kind of pulsar that hints at a previously unsuspected population of stars waiting to be found in the Milky Way: full story.

UNDER THE OVAL: No solar wind? No problem. The skies over Baffin Island, Canada, can turn green even without a geomagnetic storm. These auroras appeared during a period of "quiet" on Oct. 15th:

Photo details: Nikon D700, Nikkor 24-70mm f/2.8 lens, 1000 ISO, 6 sec.

"Last night, bathed in the glow of a full moon, the northern lights danced over Pangnirtung Fjord," reports photographer Claus Vogel. "It was a stellar night for shooting the aurora with my Nikon D700."

The display was sparked by nothing special. Baffin Island lies under Earth's auroral oval, a lopsided ring of light encircling the North Pole. Around the oval, Earth's magnetic field funnels electrically-charged particles from space into the upper atmosphere where the flurry of tiny impacts causes the air to glow green--no geomagnetic storm required.

Of course, a real storm is nice, too. Browse the gallery for examples:

Oct. 2008 Aurora Gallery
[Previous Octobers: 2007, 2006, 2004, 2003, 2002, 2001, 2000]

RAINBOWS AT NIGHT: The recipe for a rainbow couldn't be simpler. Splash sunlight across falling rain and voilĂ --a luminous arc of mythological beauty. Sunlight is crucial to the process, yet last night in Northern Ireland, a rainbow appeared long after sunset:

How is this possible? Bright moonlight did the job of the sun.

"The clear sky around the Moon and showers to my west provided the perfect environment for the formation of a lunar rainbow," says photographer Martin Mc Kenna. "It was very intense, exhibiting vibrant red, white, and blue colours visible to the naked eye. I've seen these 'bows for two nights in a row!"

The moon is still bright tonight. Readers, if rain begins to fall through the moonlight, be alert for a lunar rainbow of your own.

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 17, 2008 there were 990 potentially hazardous asteroids.
Oct. 2008 Earth-asteroid encounters:
Miss Distance
2008 QS11
Oct. 2
11 LD
470 m
2008 SH148
Oct. 4
5.8 LD
26 m
2005 GN59
Oct. 6
20 LD
1.4 km
2008 TC3
Oct. 7
3 m
2008 TZ
Oct. 10
5.3 LD
37 m
1999 VP11
Oct. 16
72 LD
860 m
2001 UY4
Oct. 18
74 LD
1.1 km
Comet Barnard-Boattini
Oct. 22
75 LD
2008 TT26
Oct. 23
3.6 LD
70 m
2000 EX106
Oct. 23
69 LD
1.1 km
2005 VN
Oct. 29
4.1 LD
116 m
4179 Toutatis
Nov. 9
20 LD
3.8 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
  a one-stop hub for all things scientific
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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