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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: 454.3 km/sec
density: 1.8 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Apr17
24-hr: A0
2340 UT Apr17
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 17 Apr 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 17 Apr 2009

NEW: Spotless Days
Current Stretch: 22 days
2009 total: 94 days (88%)
Since 2004: 605 days
Typical Solar Min: 485 days
explanation | more info
Updated 17 Apr 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
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: 3.7 nT
Bz: 2.2 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole could reach Earth on April 16th or 17th. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2009 Apr 17 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: 2009 Apr 17 2201 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
What's up in Space
April 17, 2009

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

 

EXPLOSION IN PROGRESS : The Solar and Heliospheric Observatory is monitoring an explosion in progress on the sun. The source of the blast is not a sunspot, but rather an erupting solar prominence. A coronal mass ejection emerging from the blast site is not directed toward Earth; no impact is expected. It is, nevertheless, a good show. Readers with solar telescopes should train their optics on the northeastern limb of the sun.

AURORA WATCH: High-latitude sky watchers should be alert for auroras. A solar wind stream is buffeting Earth's magnetic field and causing geomagnetic activity around the poles. Sylvain Serre sends this picture from just outside the village of Salluit in Nunavik, Canada:


Photo details: Canon EOS 30D, 800 ISO, 15 sec

"I knew it was supposed to be a good night to observe the northern lights," says Serre. "So, I went with some friends and we found the sky filled with color."

NOAA forecasters estimate a 20% chance of continued geomagnetic activity during the next 24 hours. Colorful skies may be found in Scandinavia, Iceland, northern Canada and Alaska. Stay tuned for new photos.

April 2009 Aurora Gallery
[previous Aprils: 2008, 2007, 2006, 2005, 2004, 2003, 2002]

GOLFERS LIGHT SHOW: "While golfing in Scottsdale, Arizona, yesterday I was treated to a bright light show in the sky," reports Gary J. Cooper. It was so distracting, he almost missed his putt:

Cooper witnessed a circumhorizontal arc--a rainbow-colored band of light caused by the sun shining through plate-shaped ice crystals in cirrus clouds. They are a phenomenon of spring and summer, forming only when the sun is more than 58 degrees above the horizon. As the name suggests, these arcs tend to hug the horizon, showing themselves most often over flat, sunny places like desert golf courses.

Look Fore! them, the next time you're on the green.


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 April 17, 2009 there were 1050 potentially hazardous asteroids.
April 2009 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2009 FU30
Apr. 2
8.8 LD
19
44 m
2004 VC
Apr. 3
51.3 LD
17
785 m
2002 EB3
Apr. 10
41.3 LD
16
1.3 km
2003 SG170
Apr. 19
57.7 LD
18
1.2 km
2009 FJ30
Apr. 24
9.7 LD
17
130 m
2001 VG5
Apr. 26
58.5 LD
15
2.1 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
   
  more links...
   
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