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Brophy, J. R.

Publications and source records attributed to Brophy, J. R..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2003

The ion propulsion system for Dawn

The Dawn Project's mission is to rendezvous and map the two heaviest main belt asteroids Vesta and Ceres. The Ion Propulsion System (IPS) for Dawn will be used for the heliocentric transfer from the Earth to Vesta, orbit capture at Vesta, transfer to a low Vesta orbit, departure and escape from Vesta, the heliocentric transfer from Vesta to Ceres, orbit capture at Ceres, and transfer to a low Ceres orbit.

ion propulsion asteroids spacecraft NSTAR↗
NASA NTRS2002

A model of hollow cathode plasma chemistry

We have developed a new model of hollow cathode plasma chemistry based on the observation that xenon ion mobility is diffusion limited due to resonant charge exchange reactions. The model shows that vapor phase barium atoms are ionized almost immediately and electric fields accelerate the ions upstream from the emission zone. We have also applied the model to the orifice region, where the resultant ion generation profile correlates with previously reported orifice erosion.

hollow cathode↗
NASA NTRS2001

NASA's Deep Space 1 ion engine

Derivatives of the NSTAR ion engine are being evaluated to assess their capability to meet future needs.

ion propulsion solar electric propulsion NSTAR DS1↗