Asteroid spin and surface properties

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Most asteroids have a non-spherical shape, resulting in variations in brightness with time (light curves) from which their spin period can be determined. The phase function describes the change in brightness of an asteroid as a function of solar phase angle (the angle between the directions of the Earth and Sun subtended at the asteroid). The form of the phase function varies between and among different spectral classes of asteroids, and contains information on the physical nature of their surfaces. In rare cases brightness changes can also result from albedo variations across the surface, eclipses/occultations of moons and mass ejection from impacts, volatile sublimation or spin-up. In order to detect such effects, which may cause changes in brightness or colour of as small as a few per cent, the underlying rotational light curve and phase corrections need to be well understood. This project will link ongoing observational programmes to characterise asteroid properties with development of new capabilities for moving object observations with our telescopes. It will make use of the OpenScience Observatories' Tenerife facilities PIRATE and COAST (see pirate.open.ac.uk, telescope.org), located at the Observatorio del Teide (OT), Tenerife, Canary Islands, one of the best northern hemisphere observatory sites. The observatory control system requires the addition of a module to track objects moving on solar orbits. This task will be completed in collaboration with the developers of the observatory control software. The data reduction pipeline also needs the addition of an option to deal with moving objects, and to conduct photometry of tracklets. Specifically, the student will take a leading role in the following tasks: (i) Develop and assist in implementing a software algorithm for the telescope mount to track solar system objects (ii) Develop optimized protocols for the automated monitoring of moving objects (iii) Identify opportunities to observe bright near-Earth asteroids during close flybys, which enable large phase angle coverage. (iv) Conduct long-term multi-band photometric monitoring of a sample of asteroids (v) Refine a processing-pipeline for the data stream from the OT to OU, to cater for moving objects