grains will be measured. A visual and infrared mapping spectrometer to study chemical composition of the coma and the surface of the nucleus as they change with time. A magnetometer and a plasma-wave analyzer to measure interactions between the coma and electrically charged particles streaming from the Sun. The magnetometer was also to measure the comet's intrinsic magnetic field, if it has one. See also List of minor planets and comets visited by spacecraft Deep Impact (spacecraft) (Comet flyby and impact probe, completed) Rosetta (Comet lander and orbiter, completed 2016) Champollion (spacecraft) (A cancelled comet lander mission) References NASA/Spacelink — FACT SHEET: CRAF The Comet Rendezvous Asteroid Flyby: A Search For Our Beginnings. NASA/JPL Pasadena CA, May 1987. Planetary Exploration Through Year 2000: Scientific Rationale. Solar System Exploration Committee, NASA Advisory Council, Washington, D.C., 1988. A Look Into the Beginning of the Solar System: The Comet Rendezvous/Asteroid Flyby Mission. NASA/JPL, May 1985 Outward to the Beginning: The CRAF and Cassini Missions. NASA/JPL, June 1991 External links CRAF info from NSSDC "Assessment of Planned Scientific Content of the CRAF Mission" by Drs. Robert O. Pepin and D.M. Hunten, chair and past chair, respectively, the Committee on Planetary and Lunar Exploration, of the National Academy of Sciences, 1985 "Assessment of Planned Scientific Content of the CRAF Mission" by the National Academy of Sciences, 1987 "On the Scientific Viability of a Restructured CRAF Science Payload" by the National Academy of Sciences, 1990 Proposed NASA space probes Missions to comets Cancelled spacecraft