POSSIBLE INCREASE OF SOLAR ACTIVITY IN COMING DAYS

[Ulrich Rieth]

A s t r o A l e r t

04 February 2005

Solar Terrestrial Dispatch
www.spacew.com

POSSIBLE INCREASE OF SOLAR ACTIVITY IN COMING DAYS

Over the next several days, solar activity is expected to intensify on the
eastern solar limb. The old active sunspot complex known as Region 10720 is
due to return to the north eastern solar limb during the next several days.
As it does, observers capable of observing the Sun with hydrogen-alpha solar
filters may observe increased limb activity, particularly in the form of limb
surges, but possibly extending to more impressive types of activity such as
limb sprays and post-flare loop arcades (if more energetic solar flaring
accompany the active region). For those who do not have access to solar
filters, current real-time hydrogen alpha views (and movies) of the Sun from
professional solar observatories are available through the Global H-Alpha
Patrol Network (http://www.spacew.com/sunnow).

A strong coronal mass ejection was observed on 01 February that originated
from behind the sun that presumeably is associated with Region 10720. No one
knows for certain, although the projected location of the sunspot complex
fits with the general trajectory that was observed for the coronal mass
ejection. Back-side imagery derived from helioseismic models also suggests
that the region may still be alive and capable of producing additional
energetic events.

Current observations of solar coronal activity indicates the imminent
approach of several active sunspot groups to the eastern limb, the largest of
which is the presumed return of region 10720. Surging is already visible on
the southeastern limb, associated with a new active region. Potentially
strong surging could be observed in the next 24 to 48 hours as old Region
10720 comes back into view.

Region 10720 was responsible (last month) for producing one of the hardest
(in terms of energy content) space radiation storms since 1989 (during the
last solar cycle). It produced several powerful X-class solar flares and
generated impressive auroral activity ("northern lights") across the European
regions. Whether it remains capable of producing additional influential
activity is an open question. The next two weeks will be interesting, during
which time Region 10720 (which will be renumbered when it reappears) will
rotate from the eastern side of the Sun to the western side of the Sun.


** End of AstroAlert **