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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: 513.7 km/sec
density: 0.9 protons/cm3
explanation | more data
Updated: Today at 2244 UT
X-ray Solar Flares
6-hr max: A0
2010 UT Apr30
24-hr: A0
0410 UT Apr30
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 30 Apr 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 29 Apr 2008
Far side of the Sun:
This holographic image reveals no sunspots on the farside of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 5 storm
24-hr max: Kp= 5
storm
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: 5.5 nT
Bz: 1.7 nT north
explanation | more data
Updated: Today at 2247 UT
Coronal Holes:
A minor solar wind stream flowing from this small coronal hole could reach Earth on or about April 30th. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2008 Apr 30 2203 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 Apr 30 2203 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
30 %
30 %
MINOR
10 %
10 %
SEVERE
05 %
05 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
50 %
40 %
MINOR
15 %
10 %
SEVERE
05 %
05 %
What's up in Space
April 30, 2008
MOTHER'S DAY: Give your mom a truly heavenly gift on May 11th--a subscription to Space Weather PHONE!  

4D IONOSPHERE: Today, NASA-funded researchers released to the general public a new "4D" live model of Earth's ionosphere. Without leaving home, anyone can fly through the layer of ionized gas that encircles Earth at the edge of space itself. All you need is a connection to the Internet: full story.

QUIET SUN: Experts say the sun is quiet. Indeed, the 11-year solar cycle is at low ebb. But just how quiet can a 1027 ton nuclear explosion (i.e., a star) ever be? Consider the following photo taken yesterday by Pete Lawrence of Selsey, UK:

Everywhere you look, something is happening. Along the horizon, flame-like prominences taller than Earth itself wave hypnotically. The stellar surface looks like a shag carpet; each strand is a Texas-sized jet of gas shooting up from the inferno below. At the right edge of the image floats a sinuous cloud of solar hydrogen held aloft by dynamic magnetic forces. At center stage is a bright patch of magnetism that just a few days ago became unstable and exploded, sending a "solar tsunami" shock wave through the sun's atmosphere.

That's what we mean by "quiet sun."

more images: from Cai-Uso Wohler of Bispingen, Germany; from P. Presby and J. Stetson of South Portland, Maine; from Stephen Ames of Hodgenville, KY; from Pete Lawrence of Selsey, West Sussex, UK; from P-M Hedén of Vallentuna, Sweden; from Patricia Cannaerts of Belgium;

STORMS ON SATURN: Amateur astronomers photographing Saturn this week have found something unexpected. "I was taking routine images of Saturn this evening, hoping to see some interesting features," says Ian Sharp of Ham, UK. "I was thrilled to see I had captured two storms" denoted by arrows in the picture below:

They're little more than smudges in this view through a backyard telescope, but each one is a continent-sized tempest with wind speeds as high as 1000 mph. Saturn's storms are white because their cloudtops are filled with ammonia ice crystals--think of the ice halos!--and they sometimes crackle with powerful lightning that radio receivers onboard the Cassini spacecraft have recorded on many occasions: listen.

Cassini has been monitoring the larger storm for months and now the smaller storm seems to be growing to rival it. The two are easy targets for backyard telescopes equipped with CCD cameras: sky map.

more images: from Günther Strauch of Borken, NRW, Germany; from Roman Breisch of Erdweg, Bavaria, Germany;


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. [comment]
On April 30, 2008 there were 946 potentially hazardous asteroids.
April-May 2008 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2008 FH5
Apr. 2
7.6 LD
20
17 m
2001 QO142
Apr. 6
34 LD
17
685 m
2008 GF1
Apr. 7
0.8 LD
18
10 m
2005 BE2
Apr. 10
62 LD
18
1.0 km
2005 NB7
Apr. 17
16 LD
16
705 m
2008 FU6
Apr. 22
62 LD
16
1.4 km
2005 TB
Apr. 28
47 LD
18
1.3 km
2008 HJ
Apr. 29
2.8 LD
16
34 m
2001 DQ8
Apr. 30
74 LD
17
1.1 km
2008 HG
May 5
17 LD
18
90 m
2008 DE
May 9
17 LD
16
550 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 bureau for real-time monitoring of solar and geophysical events, research in solar-terrestrial physics, and forecasting solar and geophysical disturbances.
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.
Daily Sunspot Summaries
  From the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
  more links...
©2008, SpaceWeather.com -- This site is penned daily by Dr. Tony Phillips.
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