Showing posts with label 1996. Show all posts
Showing posts with label 1996. Show all posts

Wednesday, August 24, 2011

Using Columbia to begin bringing the moon to America (1996)

Assembly of NASA's first spaceworthy Space Shuttle orbiter, OV-102 Columbia (middle image above), commenced in November 1975. The 111-ton reusable winged spaceship first reached low-Earth orbit on STS-1 (April 12-14, 1981), the Space Shuttle Program's first mission. Named for the first American sailing ship to circle the globe and the Apollo 11 Command and Service Module, Columbia completed 27 successful flights.

NASA's oldest Orbiter was also its heaviest. Unlike its sisters Atlantis, Discovery, and Endeavor, Columbia could not reach the 51.6° orbital inclination of the Russian Mir station and the International Space Station (ISS) with a useful payload in its 15-by-60-foot payload bay. This performance constraint meant that, in the Shuttle-Mir/ISS era, NASA increasingly relegated to Columbia its few remaining low-inclination, non-space station missions, such as Hubble Space Telescope servicing. Extended-Duration Orbiter modifications also permitted Columbia to remain in orbit for more than two weeks to serve as a science research platform, but such missions would become increasingly rare after research commenced on board ISS.

In an April 1996 paper presented at the 33rd Space Congress in Cocoa Beach, Florida, Carey McCleskey of the Vehicle Engineering Directorate at NASA's Kennedy Space Center proposed using the oldest Orbiter's excess mission capacity "to ignite a billion dollar, sustained enterprise on the Moon." Specifically, he advocated using Columbia as a joint NASA/private sector Earth-orbital launch platform for rocket stages bearing small lunar landers. Columbia would remain in space for only a few hours during each of its lunar lander deployment missions.

The landers would deliver to the moon teleoperated "micro-robots" akin to Mars Pathfinder's Sojourner rover (bottom image above). These would serve as proxy lunar explorers for paying visitors at "space theme parks" on Earth.

Confident that his proposal would help to build public support for U.S. astronauts to return to the moon, McCleskey wrote that
use of Columbia only makes sense for the start-up and initial take-off phases of the enterprise. The Shuttle system. . .will reach a limit which will drive the nation toward advanced space delivery systems. The use of the Shuttle for starting a lunar enterprise, therefore, is not the answer for space delivery, but rather our next opportunity.
Columbia lifted off at the start of STS-107, its 28th mission, on January 16, 2003. Eighty-two seconds after launch, a piece of foam insulation about 20 inches long broke free from its External Tank and struck its left wing. Engineers examining high-resolution video images of the impact warned of possible wing damage, but Shuttle management elected to disregard their warnings.

The oldest Orbiter's seven-person crew conducted wide-ranging science research for 16 days - long enough for the moon to wax from nearly full to full, then wane to last quarter and new. The crew beamed to Earth a breathtaking image of the last quarter moon taken on January 26 (top image above).

On February 1, 2003, the day of the new moon, Columbia fired its twin Orbital Maneuvering System engines to slow itself and reenter Earth's atmosphere. Temperatures on the Orbiter's belly tiles, nose cap, and wing leading edge panels began to climb as Columbia reentered at an altitude of 400,000 feet. About 40 minutes after the deorbit burn the wing leading edge temperature neared its peak value of about 3000° Fahrenheit.

As Columbia crossed the California coast in predawn darkness en route to its planned landing in Florida, hot plasma began to penetrate its internal structure through a breach in its left wing leading edge. Flight controllers in Mission Control in Houston puzzled over the cause of sensor failures in the Orbiter's left wing. The failures progressed aftward from the leading edge.

For observers on the ground in California, Nevada, Utah, Arizona, Colorado, New Mexico, and Texas, many of whom had observed pre-dawn Shuttle reentries before, Columbia was a fast-moving, brilliant point of light leaving behind a luminous, sky-spanning ionization trail. Veteran observers along Columbia's reentry path noted more than 20 unusual flashes around the Orbiter and peculiar bright streaks in the trail.

As Columbia crossed from New Mexico into Texas, it began to shed pieces. Meanwhile, thrusters fired automatically to compensate for increased drag on the left wing. Columbia did not give up without a fight.

Radio contact with Columbia was lost about 10 minutes after hot plasma first entered the left wing. Less than a minute later, the gutted wing folded over the fuselage. The oldest Orbiter disintegrated at an altitude of 203,000 feet just west of Dallas, Texas, killing its crew and raining wreckage over parts of eastern Texas and western Louisiana.

The STS-107 accident triggered far-reaching changes in the U.S. space program that have yet to play out fully. The most obvious of these was President George W. Bush's January 2004 call to end the Space Shuttle Program when ISS was completed, which at the time was scheduled for 2010. The 135th and last flight of the Shuttle, designated STS-135, concluded on July 21, 2011, with the landing of Atlantis in Florida. On August 16, 2011, Space Shuttle Program Manager John Shannon announced that the Shuttle Program would end officially on August 31, 2011.
"Using the Space Shuttle Columbia to Begin Bringing the Moon to America," Carey M. McCleskey; paper presented at the 33rd Space Congress in Cocoa Beach, Florida, April 23-26, 1996.

Wednesday, August 10, 2011

One-way to Mars (1996)

Painting by Pat Rawlings for NASA.


In July 1962, Bell Aerosystems Company staffers John M. Cord, an engineer, and Leonard M. Seale, a psychologist, proposed that NASA launch one man on a one-way mission to the moon. Theirs was not a suicide mission, though it was a sign of desperation. At the time they presented their radical proposal, the United States seemed to be far behind the Soviet Union in the Cold War moon race.



In the "One-way Space Man" plan (link below), a lone astronaut would launch to the moon with no means of returning to Earth as soon as the U.S. developed a rocket with engines capable of generating between 450,000 and 1,100,000 pounds of thrust. Cord and Seale estimated that this would fly in 1964 or early 1965. The Soviets, they believed, already had a rocket capable of launching a one-way manned moon mission, and would debut a rocket powerful enough to launch a multi-man round-trip moon mission in 1965. Therefore, unless the Soviet Union also opted for a one-way mission, the One-way Space Man plan would give NASA a fighting chance to win the race to land a man on the moon.



Cord and Seale estimated that the One-way Space Man would return to Earth after between 18 and 24 months on the moon: that is, as soon as the U.S. developed a rocket capable of dispatching a multi-man round-trip spacecraft to recover him. In the meantime, NASA would dispatch a steady stream of automated cargo rockets bearing food, oxygen, water, spare parts, and equipment to the One-way Space Man's small temporary lunar outpost.



Thirty-four years after Cord and Seale first presented their proposal, George William Herbert, an Information Technology professional, proposed a one-way manned mission to Mars. Herbert's plan, presented first in July 1996 at the Case for Mars VI conference in Boulder, Colorado, was not motivated by Cold War desperation, for the Soviet Union had collapsed in 1991 and the U.S. and Russian Federation had begun to merge their manned space station programs. Rather, Herbert's plan was driven by an intense eagerness to explore and settle Mars.



Herbert advocated placing on Mars a group of 35-year-old "pioneers" intent on exploring their new home for the rest of their lives. In addition to abundant exploration time, this approach would enable "a natural first step in an ongoing colonization should we choose to do so." In other words, the first humans on Mars might also become the planet's first settlers, with many more men and women (and, presumably, Mars-born children) joining them as the decades passed.



Herbert proposed a new low-cost NASA launcher, the GRAND-3, each of which would be capable of boosting three 32-metric-ton, 10-meter-diameter, solar-powered "capsules" to Mars. Herbert described GRAND-3's first two stages as "pressure fed propane/nitric acid propellant steel tank big dumb booster vehicles." The giant rocket's liquid hydrogen/liquid oxygen third stage would comprise a Space Shuttle External Tank with rocket engines bolted on.



The First Exploration Phase of Herbert's three-phase program would last for six and a half years. It would begin with GRAND-3 launch of an unmanned "pathfinder mission." Three capsules would land on Mars to scout out pre-selected primary and backup base sites. Two would set down at the primary site and the third at the backup. They would test landing accuracy, capsule design, and techniques for extracting oxygen and water from martian air and surface materials. The capsules would also carry a portion of the cargo needed for the first piloted flight.



Twenty-six months later, during the next minimum-energy Earth-Mars transfer opportunity, two GRAND-3 rockets would launch six capsules: a two-deck habitat bearing the first two astronauts; a two-deck lab capsule; and four cargo capsules bearing a 35-year supply of food and two nine-metric-ton, seven-meter-long pressurized rovers. The latter would be capable of year-long Mars traverses. After 26 more months, another pair of GRAND-3s would launch to Mars two habitats with two astronauts each, two labs, and two cargo capsules.



The Second Exploration Phase would include eight GRAND-3 launches and would last for nearly nine years. Every 26 months two GRAND-3s would boost toward Mars one habitat with two astronauts on board and five unmanned capsules "to provide additional exploration capability, science and analysis gear, and skilled personnel." Beginning with the first flight of the second phase, the Mars pioneers would have on hand a 40-year supply of food.



Herbert did not describe his program's open-ended Third Exploration Phase in detail. Every 26 months one GRAND-3 would launch a habitat with two astronauts, a cargo capsule, and a "greenhouse module" for growing food and recycling waste. Science and exploration gear would replace the food carried in the First and Second Phase cargo capsules.



Herbert estimated that his program would cost up to 35% less than one that returned its astronauts to Earth. He placed hardware development cost over a period of five years at only $1 billion per year, for a total of $5 billion. Of this optimistic total, $1 billion would be spent on rover development, $2.5 billion on capsules, $1 billion on science systems, and $500 million on space suits. Operations would cost $1 billion per year. This would include $750 million for GRAND-3 launches every 26 months and $250 million for management and science support.



Apart from the technology-oriented pathfinder mission, Herbert included no mention of precursor missions for base site selection, nor of any infrastructure other than the capsules (for example, Mars weather and radio relay satellites). Neither did he mention the need for biomedical research to determine whether humans can live for years or decades under martian conditions, which include low gravity, chemically reactive dirt, and high radiation levels.



Herbert suggested that the U.S. might eventually abandon its Mars pioneers. If abandonment were planned in advance - for example, if the decision were taken to wind down funding for the program - then NASA would launch a final six cargo capsules packed with spare parts and supplies to help ensure that the men and women on Mars could live out their natural lifespans. If abandonment were unplanned - for example, if Earth suddenly descended into a dark age - then the astronauts would eke out an existence as best they could by drawing upon their 40-year food supply and by cannibalizing derelict cargo capsules for spare parts.

"One-Way to Mars," AAS 96-322, George William Herbert, The Case for Mars IV: Making Mars an Affordable Destination, Kelly R. McMillen, editor, 1996, pp. 235-244; paper presented at the Case for Mars VI conference, Boulder, Colorado, July 17-20, 1996.



http://beyondapollo.blogspot.com/2010/09/one-way-space-man-1962.html