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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: 385.0 km/sec
density: 0.2 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A6
2330 UT Apr17
24-hr: B2
0555 UT Apr17
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 17 Apr. 10
The Earth-facing side of the sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 15 Apr 2010

Spotless Days
Current Stretch: 2 days
2010 total: 9 days (8%)
2009 total: 260 days (71%)
Since 2004: 777 days
Typical Solar Min: 485 days
explanation | more info
Updated 15 Apr 2010


The Radio Sun
10.7 cm flux: 75 sfu
explanation | more data
Updated 15 Apr 2010

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 1
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 4.3 nT
Bz: 0.4 nT south
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
SPACE WEATHER
NOAA Forecasts
Updated at: 2010 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: 2010 Apr 17 2201 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
25 %
05 %
MINOR
05 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
30 %
10 %
MINOR
10 %
01 %
SEVERE
01 %
01 %
What's up in Space
April 17, 2010

NEW AND IMPROVED: Turn your iPhone or iPod Touch into a field-tested global satellite tracker. The Satellite Flybys app now works in all countries.

 

AURORA WATCH: High latitude sky watchers should be alert for auroras. A coronal mass ejection (CME) is expected to deliver a glancing blow to Earth's magnetic field on April 17th. NOAA forecasters estimate a ~30% chance of geomagnetic activity when the cloud arrives.

NO CONTRAILS, GREAT SUNSETS: Normally, the sky around this radio air traffic control tower near Frankfurt, Germany, is criss-crossed by contrails. "But not today," says photographer Helmut Marten. "Because of the dust clouds from Iceland's Eyjafjallajokull volcano, almost all of the air traffic over northern Europe has come to a halt."

Hard and sharp-edged volcanic dust is hazardous to aircraft, clogging engines that suck it in, and pitting windows that pilots need to see through. According to Eurocontrol, the intergovernmental body that manages European air travel, about 16,000 flights across Europe have been canceled. Stranded passengers have one consolation--sunrises and sunsets of rare beauty. Browse the links below for examples.

volcanic sky shots: from René of Schiphol, Amsterdam, Netherlands; from Manuel ten Hake of Zoetermeer, The Netherlands; from Vincent Phillips of Speke, Liverpool, England; from Toine Kuiper of Leende, Netherlands; from Jeffrey Berkhout of Nibbixwoud, Netherlands; from Katie-Anne Fitzgerald of Belton North Lincolnshire UK; from Alan C Tough of Elgin, Moray, Scotland

VOLCANIC LIGHTNING: It is well known that volcanic eruptions produce strong lightning. Less well known is why? Ordinary lightning in thunderstorms is not fully understood; volcanic lightning is even more of a mystery.

To investigate, a team of researchers from New Mexico Tech has traveled to Iceland to monitor the Eyjafjallajokull volcano--and they have found it crackling with electricity:

"On the evening of April 16th, there were some small eruptions producing ash clouds up to about 6-7 km, with lightning," says photographer Harald Edens. "The sky was nice and clear, so I was able to photograph the bolts from the town of Hvolsvollur using my Nikon D700 and a 80-200/2.8 lens."

Photography is one way to monitor volcanic lightning, but the technique has limits: Ash clouds are able to hide the flashes; lightning is not always visible in daylight; glowing lava competes for attention; and so on. Radio receivers can do a better job. Lightning emits impulsive radio bursts which can be measured and counted, day or night, even through clouds of ash. "We are deploying a six-station lightning mapping array around the Eyjafjallajokull volcano," says Edens. Their analysis of the radio "crackles" could reveal much about the inner workings of volcanic lightning.


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

 
       
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, 2010 there were 1116 potentially hazardous asteroids.
April 2010 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2010 GV23
April 5
2.1 LD
19
12 m
2010 GF7
April 8
2.8 LD
18
30 m
2010 GA6
April 9
1.1 LD
16
27 m
2010 GM23
April 13
3.4 LD
17
47 m
2005 YU55
April 19
5.9 LD
15
185 m
2009 UY19
April 23
8.8 LD
18
87 m
2002 JR100
April 29
8.0 LD
19
65 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.
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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