Terry's Astronomy Thread.

[Bluearrowll]

What's in the sky tonight?
October 9, 2013

-An interplanetary shock wave, possibly the leading edge of a CME, hit Earth's magnetic field on October 8th at approximately 2015 UT (1:15 pm PDT). The impact sparked a G1-class geomagnetic storm (in progress) and bright auroras around the Arctic Circle. Lana Rupp photographed the "stunning display of color" over Borgarnes, Iceland, during the early hours of Oct. 9th below. Earth is passing through the wake of the CME where a region of high-speed solar wind continues to buffet our planet's magnetic field. NOAA forecasters, who suspect that a second CME might arrive on Oct. 9th, estimate a 65% chance of polar geomagnetic storms during the next 24 hours. High-latitude sky watchers should remain alert for auroras.

-Solar activity is picking up. New sunspot AR1865 erupted this morning (Oct. 9th at 01:48 UT), producing the strongest solar flare in nearly two months. NASA's Solar Dynamics Observatory recorded the M2.8-class eruption: movie. Earth was not in the line of fire, but future eruptions could be geoeffective as the sunspot turns toward our planet in the days ahead.

-Look for Venus far lower right of the Moon during and after twilight. Just 3/4° above Venus is 2nd-magnitude Delta Scorpii.

Astro Picture of the Day:
October 9, 2013

Source:
During the night time hours of October 8, a minor Coronal Mass Ejection (CME) impacted the magnetic field of the Earth. The impact sparked a G1-class geomagnetic storm where the northern lights could be seen as far south as Ohio. If you are a northern latitude watcher, you were given the best show however. This photo, by B.Art Braafhart of Salla, Finnish-Lapland, had front row seats to a particular intense section of the storm that pierced not only through an otherwise overcast night, but also illuminated the lake in eerie tones of green. Braafhart estimates that the storm he witnessed peaked at a Kp index of 6.33 as opposed to 5. The overcast sky contributes significantly to the eerie effect of this image. Tonight, there is a 65% chance that strong geomagnetic activity continues.