EERIE EARTHSONG: A NASA spacecraft has recorded eerie-sounding radio emissions coming from our own planet. These beautiful "songs of Earth" could, ironically, be responsible for the proliferation of deadly electrons in the Van Allen Belts. [video] [audio]
INCOMING SOLAR STORM CLOUD: Magnetic fields around sunspot 1577 erupted on Sept. 28th, hurling a coronal mass ejection (CME) almost directly toward Earth. The Solar and Heliospheric Observatory (SOHO) recorded the cloud as it raced away from the sun faster than 2.2 million mph:
NOAA forecasters estimate a 50% chance of strong geomagnetic storms around the poles on Sept 30th when the cloud reaches Earth. High-latitude sky watchers should be alert for auroras, which might be intense enough to see in spite of the full moonlight. Aurora alerts: text, voice.
HARVEST MOON: This weekend's full Moon is the Harvest Moon, the full Moon closest to the autumnal equinox. Before electric lights, farmers working after sunset relied on the light of the Harvest Moon to help them gather ripening autumn crops. Now it's just a pretty sight. Look east for the Harvest moonrise on Saturday night.
Photographer Göran Strand sends this picture of a "Harvest Moon halo" from Frösön, Sweden:
The 22-degree halo was caused by harvest moonlight shining through ice crystals in the high, thin clouds over Frösön. "It was a beautiful halo, very intense," says Strand.
Solar wind
speed: 310.5 km/sec
density: 2.0 protons/cm3
explanation | more data
Updated: Today at 1537 UT
X-ray Solar Flares
6-hr max: C2 0748 UT Sep30
24-hr: M1 0433 UT Sep30
explanation | more data
Updated: Today at: 1459 UT
Daily Sun: 29 Sep 12
Sunspot 1577 poses a slight threat for M-class solar flares. Credit: SDO/HMI
Sunspot number: 70
What is the sunspot number?
Updated 28 Sep 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
Update 28 Sep 2012
The Radio Sun
10.7 cm flux: 133 sfu
explanation | more data
Updated 28 Sep 2012
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 3 quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 6.8 nT
Bz: 5.2 nT south
explanation | more data
Updated: Today at 1536 UT
Coronal Holes: 28 Sep 12
There are no large coronal holes on the Earth side of the sun. Credit: SDO/AIA
