Recent ‘Unprecedented’ Weak Solar Wind: A solar glitch or a harbinger for the next Maunder

minimum?

Conveners: Joan Feynman* and Janet Luhmann

When: Wednesday AM. Session #1Kickoff speakers: Heather Elliott, SWRIDean Pesnell, GSFC

The Longer Perspective is Keyin considering the present

From Wikipedia website

Why are we surprised?

Ulysses found in-situ evidence of a wide band of low latitude/slow solar wind structure, together

with weak IMF and mass flux

From McComas et al., GRL 2008, also results from Ed Smith et al.

C. Lee et al. compared recent L1 data with previous cycle data for a similar phase. OMNI V statistics are similar, but B and N lower

(C.O. Leeet al., Sol.Phys. 2009)

..geomagnetic activity is reaching some all-time lows

NOAA SWPC website plot

..The still lengthening minimum has led to downward adjusting predictions of the next maximum SSN

NOAA SWPC website plots combined in wattsupwiththat cycle 24 blog

..on the Sun, weak polar fields have been an ongoing sign of something different going on

WSO data

One outcome has been a more multipolar solar minimum corona

July 2009 eclipse(Eclipse Images and coronal models from PSI corona website. SOHO LASCO C2 image.)

October ‘95 eclipse

Sputnik and Explorer 1 launched in 1957 and 1958 respectively, WSO began daily magnetic field observations in 1975, Mt. Wilson magneticfield data archives date from ~1970, etc. (Figure from NOAA SWPC)

But have we faced up to the fact that we have very limited cycle experience, space-age wise?

..and not all predictions are on-board with the Maunder harbinger scenario

Hathaway NY times plot

Over the long haul, even post-Maunder cycles have beensmaller than many ‘low’ predictions for cycle 24

Nevertheless:

-This unusual cycle transition is revealing much about whatwe know and don’t know about everything from what makessolar cycles vary to what the many consequences are.

-What will be ‘unprecedented’ is the coming cycle behavior asa test of solar dynamo theories, and our ability to connect thedynamo with its heliospheric consequences.

-Even a healthy blog on this subject has been ongoing forseveral years ….

Don’t miss this ‘stellar’ opportunity to join the debate. ComeWed. AM to give your perspectives and share your knowledge.