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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
SPACE WEATHER
Current conditions
Solar wind
speed: 297.4 km/sec
density: 3.6 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Sep24
24-hr: A0
1050 UT Sep24
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 24 Sep 08
Sunspot 1002 has faded away, leaving the sun blank. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 24 Sept. 2008
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
quiet
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 4.4 nT
Bz: 0.1 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: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2008 Sep 24 2201 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
CLASS X
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 Sep 24 2201 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
01 %
01 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
01 %
01 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
What's up in Space
September 24, 2008
AURORA ALERTS: Did you miss the Northern Lights of August 9th? Next time get a wake-up call from Space Weather PHONE.  

PROM ALERT: If you have a solar telescope, take a look at the sun. Observers are reporting a large and beautiful prominence dancing along the western limb.

SOLAR WIND LOSING POWER: In a briefing yesterday at NASA HQ, solar physicists announced that the solar wind is losing pressure, hitting a 50-year record low for the Space Age. This development has repercussions across the solar system: full story.

FADING SUNSPOT: A small sunspot emerges, flickers, and fades away in less than 48 hours, gathering attention once reserved for Jupiter-sized behemoths. Welcome to solar minimum.

This SOHO animation, spanning Sept. 21st to 23rd, shows the fleeting appearance of sunspot 1002:

The real excitement about the active region was not its size or duration, but rather its polarity. The orientation of the sunspot's magnetic field identified it as a member of new Sunspot Cycle 24. Because the year 2008 has brought so many blank suns, some observers have wondered if we are ever going to climb out of the ongoing deep solar minimum. Sunspot 1002 is an encouraging sign that the 11-year solar cycle is indeed progressing, albeit slowly.

more images: from Alan Friedman of Buffalo, New York; from N. Hebert et al. of South Portland, Maine

SUNRISE AT THE SOUTH POLE: On Sept. 21st, Ethan Dicks looked out the window of his office and saw the sun for the first time in 6 months. He quickly grabbed his camera and snapped this picture of sunrise at the South Pole:

"I am a researcher for the University of Wisconsin-Madison, running
IceCube, the large (1 km3 when completed) neutrino telescope that's under construction a mile below the ice near the South Pole," explains Dicks. "The past six months have been almost nothing but night; it's good to see the sun again."

He took the picture a full day before the Sept. 22nd equinox--the "official" date of sunrise. Geometrically, the sun should've been mostly below the horizon at the time, but refraction by the dense polar atmosphere lifted the image up for all to see.

"Polar regions are famous for mirages and early explorers sometimes wondered what was real and what illusion," notes atmospheric optics expert Les Cowley. "In Dicks' picture, several air layers of different temperature have distorted and sliced the sun. Its rays are bent as they pass between the layers to form multiple images, some inverted and some upright."

Dicks is a veteran observer of South Pole sunrises. "This is my third winter here," he says. Some sunrises are heralded weeks ahead of time by a diffuse glow on one side of the sky and the retreating shadow of Earth ("a dark blue band topped by a fringe of magenta") on the other. Eventually a sliver of sun appears, circling the horizon for days, growing in size, until finally the sun emerges in full. "When it's clear, the show is amazing. This year, we were mostly clouded out until Sept. 21st. I feel bad for folks on their first and maybe only winter-over; they missed the full sunrise."

When you're at the South Pole, though, even a fraction of sunrise can be a wonderous thing.


Sept. 2008 Aurora Gallery
[Aurora Alerts] [Night Sky Cameras]

       
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 September 24, 2008 , there were 981 potentially hazardous asteroids.
Sept. 2008 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2003 WT153
Sept. 7
5.8 LD
23
11 m
1996 HW1
Sept. 12
53 LD
12
3.7 km
2003 SW130
Sept. 19
8.6 LD
23
7 m
1998 UO1
Sept. 26
25 LD
18
2.0 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.
STEREO
  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, SpaceWeather.com -- This site is penned daily by Dr. Tony Phillips.
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