Thermal Radiation from Large Asteroids
Dr Matthew Chamberlain
Planetary Science Institute
Tucson, AZ, USA
4-5 p.m., Thursday, 21 June, 2007
School of Physics Common Room
Room 64 Old Main Building
The University of New South Wales
New thermal observations are being made in the mid-infrared and the
microwave wavelengths of Ceres, Vesta and other large asteroids.
These planetary bodies represent protoplanets left over from the
formation of terrestrial planets. There is evidence for variation
in thermophysical properties both between asteroids and on the surface
of a single asteroid. Thermal lightcurves are observed as the asteroids
rotate and these lightcurves have significant amplitudes that cannot
be explained by shape and albedo alone. Repeat observations of the
same asteroid are made under different viewing aspects and sub-solar
latitudes, and can constrain thermophysical properties of the surface.
Results are being used to refine the thermal models applied to asteroids,
some of which are two decades old, and to begin identifying surface
regions with anomalous properties.The altiplano is a 5000m elevation
plateau in the Andes of South America where are found the driest
temperate-latitude places on the Earth. This provides superb conditions
for sub-millimetre wave astronomy, opening up new windows for observation
through that are inaccessible from other temperate sites. In these
wavebands emission from dust and molecules is prominent, including
the birth sites of massive stars in our own Galaxy and the red-shifted
emission from some of the youngest galaxies in the Universe.
The audience is invited to meet the speaker beforehand
at 3.45 p.m. over wine and cheese in the Physics Common Room.