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REVISED
FORECAST: The CME launched toward
Earth by yesterday's X-flare is moving faster than
originally thought. Analysts at the Goddard Space
Weather Lab have revised their forecast accordingly,
advancing the cloud's expected arrival time to 09:17
UT (5:17 am EDT) on Saturday, July 14th. Weekend
auroras are likely.
Aurora alerts: text,
voice.
X-FLARE!
Big sunspot AR1520 unleashed an
X1.4-class solar flare on July 12th. Because the
sunspot is directly facing Earth, everything about
the blast was geoeffective. For one thing, it hurled
a coronal mass ejection (CME) directly toward our
planet. According to a forecast
track prepared by analysts at the Goddard Space
Weather Lab, the CME will hit Earth on July 14th
around 09:17 UT (+/- 7 hours) and could spark strong
geomagnetic storms.
The explosion also strobed Earth with
a pulse of extreme UV radiation, shown here in a
movie recorded by NASA's Solar Dynamics Observatory:
The UV pulse partially ionized Earth's
upper atmosphere, disturbing the normal propagation
of radio signals around the planet. Monitoring stations
in Norway,
Ireland and Italy
recorded the sudden ionospheric disturbance.
Finally, solar protons accelerated
by the blast are swarming around Earth. The radiation
storm, in
progress, ranks "S1" on NOAA space
weather scales, which means it poses no serious
threat to satellites or astronauts. This could change
if the storm continues to intensify. Stay tuned.
Realtime
Space Weather Photo Gallery
SOUTH
POLE AURORAS: In a possible preview
of the light show to come, bright auroras have been
dancing over Earth's south pole. Robert Schwarz
took this picture on July 12th from the grounds
of the Amundsen-Scott South Pole Station:
"Yesterday we had some of the
best auroras I've seen," says Schwarz.
Despite its high latitude, the South
Pole is not always a good place to see the lights
because it is often located in the "doughnut
hole" of the aurora
oval. July 12th was an exception: "Look
carefully at the picture and you can see the actual
Pole in the foreground" Schwarz points out.
NOAA forecasters estimate a 55% chance
of strong polar geeomagnetic storms on July 14th
when a CME is expected to crash into Earth's magnetic
field. More South Pole auroras could be in the offing.
Realtime
Aurora Photo Gallery
Realtime
Noctilucent Cloud Photo Gallery
[previous years: 2003,
2004,
2005, 2006,
2007, 2008,
2009,
2011]
