WASHINGTON, July 29 (UPI) -- Part 1 of 2
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Editor's Note: Planners in NASA's Exploration Directorate recently gave United Press International an exclusive briefing on the steps they envision to fulfill President Bush's new vision for space exploration. These steps include designing the vehicle to fly back to the moon as well as the new fleet of atomic-powered spacecraft that may open up astronaut visits to deeper in space. In Part 1, NASA explains the different approach it is researching to achieve the first human visits to the moon since Apollo 17 in December 1972. When American astronauts make their return, some of their missions will resemble the old Apollo voyages and some will be far more advanced.
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WASHINGTON, July 29 (UPI) -- Inside NASA, planners have begun to assemble teams that are looking deep inside President George W. Bush's new vision of space exploration. Their goal: define the characteristics of the first new piloted spaceship since the space shuttle, and establish the initial steps and stages by which these new craft will attempt a series of moon landings.
Inside NASA's Exploration Mission Directorate, a requirements group is busily working to put substance into the new assault on the moon.
What are NASA's requirements for the new moonship? According to Mike Lembeck, who heads the requirements group, they compose a soup-to-nuts catalog of everything moonwalking astronauts will need on their initial forays: How big will the ships be? How many astronauts will they carry? How will their launching rockets get them there? When they get to the moon, what will be the profiles of their explorations, and what science will they seek?
Soon, the planners will call upon industry to start designing the ships.
"We hope to get an RFP (request for proposal) out by January on the CEV (crew exploration vehicle), and have a fly-off of two teams in 2008," Lembeck said.
The fly-off, a staple of contracting for military aircraft, will be new to NASA's manned space efforts.
Lembeck described a process by which the space agency will choose a pair of teams, each with a complete design for the CEV, its booster rocket, and the method by which it would achieve Earth orbit and become part of a manned moon flotilla.
Each contractor-led team would include subcontractors that would provide the moonbound astronauts with equipment, life support, rocket thrusters and onboard navigation systems. The Earth orbit fly-offs would pit one complete design against another, with NASA choosing the winner, who would build the final ships.
Reusability is likely to be a valuable component, but initially not essential, Lembeck said. Rather, it is what makes the most sense in designing the 21st century lunar craft.
Lembeck's group released an initial study request last month to begin gathering issues and potential needs for the spaceships, clearing the path so the actual contract request in January can be more focused. They want the moon version of the CEV to contain systems that can be evolved to sustain deeper trips into space, such as voyages to asteroids or manned flights to Mars.
Right now, however, the shape of the craft is not a main priority.
"We aren't focused on the mouldline," Lembeck said, only what needs to be inside. Current thinking, he said, is the lunar CEV might be sized for four astronauts -- the Mars ship for six.
"We are thinking in terms of two-person teams for EVAs," he explained. EVAs, or spacewalks, would be designed around a minimum of two astronauts outside at a time. Studies will also determine by the end of this year if the CEV and the lunar lander will be separate spacecraft, or if they can be combined into a single ship. The current thinking by mission planners is attempting a single lunar landing per year, starting no later than 2020, but perhaps as early as 2017.
Lembeck said NASA is planning to have the fly-off winner design the CEV ships in a series of "spirals," or complete packages of spacecraft systems and subsystems:
-- Spiral one would comprise the early CEV capable of carrying crews into orbit for testing flights.
-- Spiral two would consist of true moonships, able to stay on the moon from a few days to a week.
-- Spiral three would be the most capable ships, which could extend human presence on the moon up to three months, basically establishing an initial lunar base.
NASA planners currently are focusing on a three-part plan to return to the moon that they call trade studies.
During Project Apollo in the 1960s and '70s, astronauts flew into Earth orbit aboard a giant Saturn V rocket carrying an Apollo command ship and a separate landing craft. The top stage of the rocket blasted the lunar duo to the moon, where the lander detached from the capsule mothership and descended to the surface, remaining there for up to nearly three days.
The first return flights under the new plan would strongly resemble the most advanced Apollo missions.
"These first missions would follow a minimalist approach," Lembeck said. They might employ separate transfer and landing systems, carrying the spaceship elements together until moon orbit, as did Apollo, then detaching for landing at relatively safe locations along the moon's equator. Astronauts would then stay on the surface for up to a week's duration.
The second wave of flights would be more complex. The elements for the flight actually might be assembled at the L-1 point -- the Lagrange point, about 200,000 miles up, at which the gravitational influences of the Earth and the moon cancel each other out.
Following assembly at L-1, the craft then would embark toward the moon, following a flight path that would cover virtually all of the moon's regions and allowing landings in more scientifically interesting, but more potentially hazardous, locales. Stay times would also average as long as a week.
The third wave would consist of the most ambitious missions currently being considered. These would require the most capable CEVs and landers, with their components assembled either in low Earth orbit or at L-1. The ships would land at the moon's poles, establish base camps, and stay 45 days and longer. These outposts then would become the first U.S. lunar bases.
Lembeck noted that astronauts on these later missions would bring equipment and tools that would be needed on a Mars outpost, making the first moon bases the testing grounds for the Mars assault.
While planners already are addressing CEV and moon-mission designs, a team of researchers at NASA's Goddard Spaceflight Center in Greenbelt, Md., is completing an initial review of the scientific objectives of the landings. For the return to Earth, the directorate is studying various types of configurations, including a rocket-assisted setdown on land, like the Russians use on their Soyuz capsules. Another option involves descending directly to Earth from moon orbit, as did the Apollo astronauts. The teams are studying the moonship's launching rockets as well.
Lembeck said these reviews include the size of the boosters, the methods by which the astronauts could escape a launching accident, and whether an engine loss could be sustained and still allow the flight to continue.
The planners also are reviewing the entire suite of space equipment, including new designs for spacesuits, habitats that could be built on the surface, what crews would need to construct them and the kinds of robots they would need to accompany them on their traverses across the moon's rocky terrain.
For longer journeys into space, however, future astronauts will need a whole new kind of rocket power -- and the means to generate power as well.
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Next: NASA's new atomic rocket
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Frank Sietzen covers aerospace for UPI Science News. E-mail [email protected]
