WHY WON'T THE SUPERNOVA EXPLODE? A question has been troubling astronomers: Why won't the supernova explode? Although real stars blow up, the best computer models of dying stars do not result in much of a bang. NASA has launched a new observatory named "NuSTAR" to seek out the missing physics of stellar explosions. [video] [full story]
DEPARTING SUNSPOT: Big sunspot AR1504, the source of so many auroras on June 16th and 17th, is leaving the solar disk. Dave Gradwell of Birr, Ireland, photographed the active region yesterday as it approached the sun's southwestern limb:
"AR1054 is waving goodbye after putting on a great show," says Gradwell.
Although the sunspot is not directly facing Earth, it could still affect our planet. Magnetically speaking, Earth is well-connected to AR1504's location on the southwestern limb. A solar flare now could accelerate charged particles, which would be guided in our direction by curved lines of magnetic force. NOAA forecasters estimate a 10% chance of M-class solar flares from AR1504 during the next 24 hours. Solar flare alerts: text, voice.
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Solar wind
speed: 420.3 km/sec
density: 0.6 protons/cm3
explanation | more data
Updated: Today at 1506 UT
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X-ray Solar Flares
6-hr max: B4 1055 UT Jun21
24-hr: B4 1055 UT Jun21
explanation | more data
Updated: Today at: 1500 UT
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Daily Sun: 21 Jun 12
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Sunspot 1504 is about to disappear over the sun's SW limb, ending the threat of Earth-directed eruptions. Credit: SDO/HMI
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Sunspot number: 46
What is the sunspot number?
Updated 20 Jun 2012
Spotless Days
Current Stretch: 0 days
2012 total: 0 days (0%)
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 821 days
Typical Solar Min: 486 days
Updated 20 Jun 2012
The Radio Sun
10.7 cm flux: 104 sfu
explanation | more data
Updated 20 Jun 2012
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Current Auroral Oval:
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Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
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Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 1 quiet
explanation | more data
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Interplanetary Mag. Field
Btotal: 6.1 nT
Bz: 1.9 nT north
explanation | more data
Updated: Today at 1506 UT
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Coronal Holes: 21 Jun 12
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A coronal hole is emerging over the sun's NE limb. Credit: SDO/AIA.
