Solar Activity Forecasting for use in Orbit Prediction n Ken Schatten n colleagues - Scherrer, Svalgaard, Wilcox, Sofia, Hoyt, Pesnell, + others.

OUTLINE n Solar Forecasting use in Orbit Determination n Solar Activity Prediction Difficulty: Chaos n Methods of Solar Activity Prediction n Intro to “Precursor Techniques”:A Puzzle! n Solar Precursors /SODA index n Current Status of Solar Cycle #23 n Early Prospective of Solar Cycle #24 n Conclusions

Solar Activity Forecasting For Use In Orbit Determination

Solar Activity Prediction Difficulty

Real Life n Give an example or real life anecdote n Sympathize with the audience’s situation if appropriate

Methods of Solar Activity Prediction : NASA panel n Even/Odd n Spectral n Recent Climatology/Climatology n Neural Networks n Precursor: Geomagnetic Precursors Solar Precursors

Methods of Solar Activity Prediction n TABLE OF PREDICTED SUNSPOT #

Intro to “Precursor Techniques”:A Puzzle! n Ohl, Brown and Williams found: near solar minimum, Geomagnetic Activity Fluctuations correlated with size of the next solar cycle! n A Puzzle! How could Terrestrial events affect future solar events? demanded further investigation.

Solar Precursors /SODA index n General dynamo theory n MHD dynamo theory n Solar Babcock model n Solar Dynamo Method - Magnetic fields on the Sun are the precursors for future fields. This helps explain geomagnetic precursors. n SODA (SOlar Dynamo Amplitude) Index

General Dynamo Theory

Solar Babcock model

Solar Precursors /SODA index

n previous precursor method:only estimate cycle from polar field at sunspot minimum n Now continuously monitor solar dynamo oscillating between toroidal and poloidal field components n Hence learn future activity changes, as dynamo is continuously regenerated, rather than single snapshots near solar minimum.

Solar Precursors /SODA index

Current Status of Solar Cycle #23

Early Prospective Solar Cycle#24

Conclusions n Cycle #23 is an interesting one - against Even/Odd - 1st cycle this century. n Our prediction of smaller cycle seems to be holding. n With SODA index, monitor solar dynamo oscillating toroidal and poloidal fields. n #24?- Very preliminary, but early field measurements show a rapidly rising polar field.