Our next Big Apple Colloquium is just about to happen! Please join us in this joint AMNH/NYU/Columbia Event
Next Wednesday March 9, 2011
Coffee from 3:00-3:45PM out side the Linder Theater
Colloquium 3:45-5:00PM
Reception in the Astor Turret 5:30-7:30PM
The flywheels of helios: making sense of how the Sun (and other stars) go round
Steven Balbus
Ecole Normale Superieure de Paris, and
Princeton University Observatory
A B S T R A C T
Helioseismology has become precision tool that has allowed the inner
rotation pattern of the Sun to be elucidated. While the radiative zone is
well modeled by solid body rotation, the turbulent convective zone shows
a regular pattern of differential rotation. Surfaces of constant angular
velocity are, roughly speaking, poleward-opening cones, coaxial with the
rotation axis. In this talk, I will show how a few simple physical
ideas and mathematical techniques are able to reproduce these observations
with striking fidelity. The inner and outer boundaries of the convective
zone exhibit strong deviations from the conical pattern; these "anomalies"
offer valuable clues to the stresses that are present in these regions.
If correct, the principles of the theory should be applicable to a
wide class of stars, including those with fully convective envelopes,
and possibly to the rotational dynamics of convective planets.
Access to the colloquium and Linder Theater can be gained through the 77th Street entrance to the museum. The Linder theater is on the first floor of the museum near the Hall of Human Origins. Guards can direct you when you come in. The Astor Turret is on the 4th floor adjacent to the Wallace Hall of Mammals and Their Extinct Relatives. For questions regarding access, please contact Gwen King at gking@amnh.org
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