Historically, the only way to deliver a scientific probe to one of our neighboring planets - or to any other object of interest in space - has been to launch it aboard a rocket capable of boosting it to sufficient speed, then waiting while it coasts toward its destination. Then, often many years later, it arrives on the scene, where it must use a substantial amount of chemical propellant - carried at the expense of added science payload - to enter orbit. If it is physically impossible to carry enough fuel to stop, the craft typically might zip right on past its target - gathering as much information as it can in the days or weeks of its passage.

There has to be a better way…

True, trip times often can be reduced by conducting well-timed planetary flybys, catching a gravity boost en route to the final destination. But even so, the wait for scientific returns is excruciatingly long in career terms. Moreover, what science data is returned is all too often limited in its richness by constraints on craft size and power - constraints imposed by the limitations of conventional propulsion systems.

It is our view that scientists should be enabled to expect much more; more plentiful and more powerful instruments; more comprehensive and more detailed data capture and more timely return of data - for more bounty of discovery.

Imagine a deep-space mission enabled by a spacecraft with a high-energy power source capable of high-fidelity data gathering and transmission back to Earth. http://nmp.nasa.gov/ds1. [Sherry: hyperlink the bolded words]

Imagine that the same craft can slow down, achieve orbit and serve as a platform for long-duration observation of planet or celestial body - before powering up thrusters and heading to another research destination.

This is the vision for next-generation space science that informs and motivates the work of the In-Space Propulsion Technology Program.

It is the propulsion technologies we have delivered (read the stories HERE and HERE) and intend to continue delivering that will significantly further our efforts to turn this vision into reality.