~ Space Weather Update~ CME IMPACT, GEOMAGNETIC STORM

CME IMPACT, GEOMAGNETIC STORM : Arriving a little earlier than expected, a CME hit Earth's magnetic field on Oct. 2nd at approximately 0200 UT. The impact sparked a G2-class geomagnetic storm with auroras across Canada and several northern-tier US states. Alan Dyer sends this picture from Gleichen, Alberta:

After the CME hit "I made a point of checking the sky and, sure enough, a fairly bright aurora was present all across the northern horizon," says Dyer. "The camera picked up red bands as broad and intense as I've seen."

The show's not over. Solar wind in the wake of the CME is blowing strong while magnetic conditions favor more storming. High-latitude sky watchers should remain alert for auroras. Aurora alerts: text, voice.

Realtime Aurora Photo Gallery

THE INSTIGATING CME: The CME that hit Earth's magnetic field today left the sun on Sept. 30th, propelled by an erupting magnetic filament. SOHO photographed the CME at the start of its journey, racing away from the sun at 2 million mph (900 km/s):

The CME was impressive, but the underlying explosion was even more so. One movie from NASA's Solar Dynamics Observatory shows the self-destructing filament in the context of the whole sun. Another movie zooms in for a closeup. It catches the filament ripping through the sun's atmosphere and leaving behind a beautiful "canyon of fire."

NOAA forecasters working through the government shutdown estimated an almost-even 45% chance of polar geomagnetic storms when the CME arrived. The CME justified those relatively high odds, sparking a G1-class geomagnetic storm around the poles. Geomagnetic storm alerts: text, voice.

Realtime Space Weather Photo Gallery

COMET ISON'S FLYBY OF MARS: In two months, Comet ISON will make a spectacular flyby of the sun. First, though, it has to fly by Mars. Today, the comet is passing by the Red Planet only 0.07 AU (10.5 million km) away. This is giving Mars satellites and rovers our first close-up view of the sungrazer: video.

Amateur astronomers on Earth are watching the close encounter from afar. This photo from Malcolm Park of Oak Heights, Ontario, shows the location of the comet relative to Mars just before sunrise on Sept. 29th:

At closest approach on Oct. 1-2, Mars and Comet ISON will be approximately 2^o apart. While Mars is visible to the unaided eye (it shines almost as brightly as a first-magnitude star), ISON is not. The comet is still far from the sun and, as it crosses the orbit of Mars, it has not yet warmed enough to reach naked-eye visibility. Reports of the comet's brightness vary from 12th to 14th magnitude, which means a mid-sized backyard telescope is required to see it.

Mars and ISON rise together in the eastern sky a couple of hours before the sun. Amateur astronomers, if you have a GOTO telescope, enter these coordinates. Visually, Mars will be easy to find on the mornings of closest approach, not only because the planet is relatively bright, but also because the crescent Moon will be passing right by it. Sky maps: Oct. 1, 2.

New images of the comet are coming in every day. Browse the gallery for the latest views:

Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES

Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 6 storm
explanation | more data

Interplanetary Mag. Field
B_total: 5.1 nT
B_z: 2.1 nT south
explanation | more data
Updated: Today at 1607 UT

Coronal Holes: 02 Oct 13

There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.