The distances between stars is so great that with existing propulsion technology a probe would travel tens of thousands of years before reaching our nearest neighboring star.

Even with the most ambitious new propulsion technology based on known physics, it would still be extremely difficult for a probe to reach that far within 50 years.

To overcome these limitations to practical interstellar space travel, new propulsion physics is being sought by the Breakthrough Propulsion Physics program. These six research selections are an early step in this process.

"Intriguing developments have appeared in recent scientific literature that can serve as starting points for this kind of research," said Marc Millis, the project manager for the program at Glenn. "The Breakthrough Propulsion Physics program is the beginning of NASA�s effort to systematically assess these findings and theories. "At this stage of research, success is defined as learning more about these developments rather than achieving breakthroughs," Millis added.

The proposals were selected after a two-stage peer review process. In the first stage, 50 specialists from academia, government and industry scored the 60 proposals received. In the second stage, government reviewers selected a variety of approaches from the top ranking proposals.

The proposers will negotiate for grants, contracts or cooperative agreements worth a total program value of $430,000. The principal investigators and a brief description of the work they proposed follow:

1. John Cramer (University of Washington, Seattle, WA) proposed a test to see if changing energy flow can affect inertia as suggested in 1991 by James Woodward, in the journal Foundations of Physics Letters. If there is such an effect, it may be exploited to develop a new method of space propulsion. In any case, the research will add to the understanding of how inertia is tied to the surrounding matter of the universe.

2. Jordan Maclay (Quantum Fields LLC, Richland Center, WI) and MEMS Optical Inc. (Huntsville, AL) proposed an experimental and theoretical study of quantum vacuum energy. The experiments will use micro-electromechanical devices to test force and energy effects predicted by quantum electrodynamics.

3. Harry Ringermacher (General Electric Corporate Research and Development, Schenectady, NY) with the collaboration of researchers from Washington University, St. Louis, MO, and United Technologies Research Center, East Hartford, CT, proposed a magnetic resonance experiment to test a theory linking electromagnetism, mass, and time. Ringermacher originally published the theory in 1994, in the journal Classical and Quantum Gravity.

4. Glen Robertson and Ron Litchford (NASA Marshall Space Flight Center, Huntsville, AL) proposed an experimental study of possible links between superconductors and gravity as recently discussed in several scientific journals. They plan to use a torsion balance, similar to those used to search for material-dependant gravitational effects, to search for superconductor-gravity effects.

5. Kevin Malloy (University of New Mexico, Albuquerque, NM) and Raymond Chiao (University of California at Berkeley, Berkeley, CA) proposed experiments and theoretical work on "superluminal quantum tunneling," an effect where light appears to pass through barriers faster than it travels through normal space. The proposed research will critically examine some of the faster-than-light hypotheses associated with this effect.

6. Serguei Krasnikov (Altamonte Springs, FL) proposed to theoretically assess the necessity of "negative energy" suggested in recent scientific literature on hyperfast travel. The possibilities for enabling hyperfast travel is more feasible if negative energy is not required.