Accepted Cycle 9 Observing Proposals

Proposal Number: 09100452

Title: High Resolution Imaging and Spectroscopy of 8P/Tuttle

PI Name: Damian Christian

We proposal a 50 ksec ACIS-S observation of the brightest known comet available during Chandra Cycle 9, 8P/Tuttle (2008). The comet will have close passage by the Earth in January 2008, with minimum Earth-comet distance of 0.25 AU and maximum visual brightness V~5.9. We will: search for changes in the spectra as a function of distance from the comet's nucleus and spectral changes across the x-ray bow shock; 2) investigate the spectral changes as a function of changes in the Solar Wind (such as, composition, velocity, and type) by comparing our results with real time solar wind monitors on board ACE, SOHO and STEREO; and 3) test the latest self-consistent physics-based charge exchange models model against the ACIS-S spectra and derive minor ion abundances.