Professor Bernard Cooper Lecture 2013

Probing the Solar Corona with Comet Lovejoy

Dr. John Raymond
Harvard-Smithsonian Center for Astrophysics

4 pm Thursday April 25 in White Hall G09

Followed by:

• 6 pm – Reception (TBA)
• 7 pm – Public Lecture “The Life and Death of a Sun-grazing Comet” in Ming Hsieh G20

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Abstract: In December 2011, a comet nucleus more than 500 meters in diameter passed just 0.2 solar radii above the surface of the Sun. It survived for 1.6 days after closest approach before it disintegrated. The comet was observed in the Ultraviolet above 2 solar radii during its approach and in the Extreme Ultraviolet at lower heights. As it deposited gas and dust along its path, it provided a probe of density and temperature in the corona along with the comet outgassing rate and composition. We discuss the interaction between gas from the comet and the solar wind at the larger heights, along with the interaction with coronal plasma. We combine basic ideas from atomic physics, fluid dynamics, the physics of solids and plasma physics to explain the observed behavior.

Speaker

Dr. Raymond is a physicist at the Harvard-Smithsonian Center for Astrophysics, where he studies spectra of the solar corona. He specializes in the physics of solar eruptions, including observations of shock waves, magnetic reconnection and heating. He also studies more distant objects, including the shock waves generated by supernova explosions and the winds from disks surrounding black holes. He has participated in NASA missions that performed ultraviolet observations.

Cooper Lecture Series

2013 John Raymond, Harvard-Smithsonian Center for Astrophysics
Probing the Solar Corona with Comet Lovejoy

2012 John Mather, Goddard Space Flight Center
James Webb Space Telescope: Science Opportunities and Mission Progress

2011: Henry van Driel, University of Toronto
A New Spin on Light

2010: Alexander Demkov, University of Texas-Austin
Emerging phenomena in functional oxide heterostructures

2009: Bill Dorland, University of Maryland-College Park
Turbulence in 5 dimensions

2008: David Newman, University of Alaska-Fairbanks
Plasmas as a prototypical complex system: self-organized criticality as a paradigm for plasma transport

2007: David Jiles, Cardiff University
Non-linear behavior in magnetic materials

2006: Myriam Sarachik, City College of New York
Molecular Nanomagnets

2005: Hari Manoharan, Stanford University
Manipulation of matter at the spatial limit

2004: David Landau, University of Georgia
A new approach to Monte Carlo simulations in statistical physics