An artist's concept of earlier proposed Pluto-Kuiper Express spacecraft. Photo: NASA/JPL

A team led by the Southwest Research Institute (SwRI) and the Johns Hopkins University Applied Physics Laboratory (JHU APL) has just completed a NASA-funded, "Phase A" design study for a Pluto-Kuiper Belt mission. This team, called "New Horizons," was one of two selected by NASA's Office of Space Science early this summer and funded at a level of $450,000 to conduct Pluto-Kuiper Belt mission studies. The principal investigator of the New Horizons Pluto-Kuiper belt mission study is Dr. Alan Stern of SwRI. The New Horizons study team consists of over 20 scientific experts in Pluto and Kuiper Belt studies, along with almost 100 engineers and other personnel at SwRI, JHU APL, Stanford University, Ball Aerospace, and NASA's Goddard Space Flight Center.

Pluto is the most distant planet known and the largest member of the Kuiper Belt. Kuiper Belt Objects -- a class of objects composed of material left over after the formation of the other planets -- have never been exposed to the higher temperatures and solar radiation levels of the inner solar system. Pluto has large quantities of ices of nitrogen and simple molecules containing combinations of carbon, hydrogen, and oxygen that are the necessary precursors of life. These ices would be largely lost to space if Pluto had come close to the sun. Instead they remain on Pluto as a sample of the primordial material that set the stage for the evolution of the solar system as it exists today, including life.

"NASA asked us to perform a detailed feasibility study for flying a mission to explore Pluto and its giant satellite Charon, and to then go on to the Kuiper Belt." Says Principal Investigator Stern, "We found the mission to be feasible with technologies that are essentially off the shelf for deep space exploration. We also found that a launch as soon as December 2004 can be accomplished."

The New Horizons team studied flying a spacecraft equipped with sensitive, miniaturized cameras, a radio science instrument, ultraviolet and infrared spectrometers, and space plasma experiments. The study team found that this combination of instruments is essentially ideal to characterize the global geology and geomorphology of Pluto and its moon Charon, to map their surface compositions, and to characterize Pluto's atmosphere and its atmospheric escape rate. "These are the very objectives NASA set forth as goals for the Pluto-Kuiper Belt mission," says New Horizons Payload Manager Mr. William Gibson, also of SwRI. "We also found that all of this can be accomplished with a significantly smaller, lighter, and far less power hungry spacecraft than the famous Voyager outer planet reconnaissance missions. It's a real step forward for outer planet exploration."

The New Horizons team designed a complete mission, including spacecraft, trajectory, instruments, and even education/public outreach plans for NASA during the Phase A study. Its mission flies to Pluto using a gravitational boost from Jupiter. "This reduces the necessary flight time and saves money," notes Stern. "The savings comes from the fact that by using Jupiter's powerful gravity as a slingshot, NASA can afford to launch the mission on a smaller launch vehicle. Our plan also saves money by using many subsystems already designed for other recent JHU APL planetary missions; this way, NASA gets the maximum leverage on past investments. Beyond saving dollars, this re-use of existing subsystem designs also reduces risk and speeds the project development schedule."

Should NASA select a Pluto-Kuiper Belt mission for development, it would follow the management philosophy of NASA's highly successful Discovery Program, with a principal investigator-led team representing academia, industry, NASA centers, and other communities. Launch would occur in either December 2004 or January 2006, with the spacecraft arriving at Pluto sometime between 2014 and 2018, depending on the type of launch vehicle and the year of launch. Along the way to Pluto, New Horizons will fly through the Jupiter system. Kuiper Belt object flybys would occur in the years following the Pluto-Charon flyby.

SwRI is an independent, nonprofit, applied research and development organization based in San Antonio, Texas, with more than 2,700 employees and an annual research volume of more than $315 million.