Andrew Coates
Biography & lecture abstracts
 |
Lecture Aeronomy-1: The ionosphere of Mars
Mars has a carbon dioxide-rich atmosphere with surface pressure about 1% of Earth's atmospheric pressure. Mars lacks a global magnetic field, but has areas of remanent magnetization concentrated in the Southern hemisphere, evidence that the planet had a global magnetic field 3.8 billion years ago. At the top of the Martian atmosphere there is an ionosphere sustained by solar illumination, transport and some particle impacts. In this talk we review the Martian ionosphere and what has been found about its composition, production and loss processes, structure and emissions from space missions including Mars Express.
Lecture Aeronomy-2: The Mars-solar wind interaction
Since Mars lost its magnetic field, the solar wind has been able to penetrate to exospheric and atmospheric altitudes. Here we review the solar wind interaction region with Mars at higher altitudes than the ionosphere. First, we discuss the extent of the Martian exosphere, and solar wind conditions at Martian orbit and their variability both now and through time. Then we discuss the solar wind interaction region, which includes a bow shock, an induced magnetosphere boundary and a photoelectron boundary. We review the processes at work in these regions, the properties of the boundaries and measurements from relevant space missions.
Lecture Aeronomy-3: Atmospheric escape
Plasma escape from the ionosphere of Mars is important as it affects atmospheric evolution on long timescales. Particles from the atmosphere and ionosphere are able to escape in a number of ways to space. These include thermal escape of light species from the atmosphere, and solar wind-driven nonthermal mechanisms which can remove heavier ions as well as light ions. These include pickup ions from the Martian exosphere, bulk plasma escape along the Martian tail, and photoelectron-induced ambipolar escape. Here we review the processes and the measurements from spacecraft including Phobos, MGS and Mars Express which have revealed them.
Lecture Aeronomy-4: Comparative plasma interactions
In addition to Mars, there are a number of unmagnetized objects in the solar system where we have recent plasma measurements, including Venus, our Moon, and icy satellites such as Titan, Enceladus and Rhea. In addition, missions to comets and Jupiter have revealed the plasma environment of comets, Io and Europa. Here we review processes which are similar at these objects, including ion pickup. We also discuss recent plasma and field measurements at these objects from space missions including Venus Express, Cassini-Huygens, and DS1. We examine similarities and differences in the plasma interactions. We also look at prospects for the future.