Who Invented The Space Shuttle

Help wanted: replacement for rockets

Rockets, says one technology historian. Time to move on from the today's technology to something better.

"If space is the final frontier, why are we still using the same technology that took Yuri Gagarin into orbit a half-century ago," asks Jonathan Coopersmith of Texas A&M University in College Station. "The answer is economics: Rockets just cost too much and are inherently limited in how cheap they can get."

In the current Space Policy journal , Coopersmith looks at the history of cost-cutting for getting pounds of stuff into orbit with rockets, the contenders for replacement technologies and reasons we might want to consider spending tax money on them.

Why? Amid a fierce fight today among firms to build a rocket to replace the space shuttle retiring with next month's final Atlantis launch, he suggests some of the development dough would be better spent on a newer technology than one invented by Chinese alchemists at least eight centuries ago, chemical rockets.

All chemical rockets, whether using solid fuels like the space shuttle's side-mounted booster engines or liquid fuels such as kerosene or liquid hydrogen, rely on chemical energy, in a process better known as burning, to thrust a rocket skyward. There is only so much energy released in breaking the bonds between atoms that this entails.

Aerospace engineers rate the efficiency of propellants in terms of "specific impulse," the change in momentum each pound of fuel provides, a quantity measured in seconds. For chemical rockets, this value tops out around 453 seconds, seen in the space shuttle's main engines. That's pretty low. For comparison, the ion thrusters aboard NASA 's Dawn mission now closing in on the asteroid Vesta, which rely on radio waves liberating electrons from Xenon gas atoms, have a specific impulse of 3,100 seconds. Sadly, ion rockets provide thrusts far too weak to get a piece of paper off the ground, much less a satellite.

"Rockets work well enough for the people who are able to pay for them," Coopersmith says. But not well enough those dealing with limited budgets, he says, noting the insurance premium on satellites can run 11% to 20% of its cost, a hundred times more expensive than insuring a Boeing 747 . "It's worse than paying for a teenage driver," he says. From a historical perspective, he compares the situation to paying craftsman to create linen shirts for rich folks in colonial times. "They worked great for people who could afford them," he says. "But we needed a new technology before everyone could wear nice shirts.

June 26, 2011

A team at Southern Illinois University Edwardsville has developed a new website, IceHunters, to challenge the public to discover Kuiper Belt objects in the outer solar system. It is hoped that among the myriad of new objects found by IceHunters there will be an object (or maybe even objects) with just the right orbit to carry it on to a rendezvous with NASA's New Horizons spacecraft. Spain is on track to become the first European country to have a dual Earth observation system, radar and optical, for both civilian and military use. Defense Minister Carme Chacon said radar technology installed on the satellite, which is totally of Spanish design and manufacture, will enable up to 100 images of the Earth's surface to be taken per day at a resolution of up to 1 yard. In three years' time, this capacity will be joined by that of the Ingenio satellite and its optical technology. (6/26) In a few days, four astronauts will take the lift to the top of the launch tower at Cape Canaveral in Florida, and settle in their seats on the space shuttle Atlantis. The crew will wait patiently until, with only eight seconds of countdown remaining, the shuttle's massive turbo pumps will force several hundred thousand gallons of liquid hydrogen and oxygen together inside the spacecraft's three main engines. In seconds, temperatures in the engines will soar to 6,000C and super-heated steam will blast from the spaceship. Two boosters, containing an explosive mixture of aluminum powder and perchlorate oxidizer, will be ignited; the giant bolts holding the straining shuttle to the ground will be blown open and, if all goes well, Atlantis will rise on a pillar of white vapor on its way into orbit – and history. The last flight of a space shuttle will have begun. (6/26) Historians often have focused on Oklahoma's pioneer legacy, from Indian Territory to land runs, early statehood and the development of towns and cities, but Oklahomans also have helped pioneer aviation and the exploration of space. Starting with Gordon Cooper in 1959, eight astronauts with Oklahoma background have joined crews on significant space missions. Scientists and engineers from Oklahoma also have played significant roles. Thanks to the Adult Space Academy offered at the U.S. Space & Rocket Center in Huntsville at the end of each summer, I now understood the attraction of baseball fantasy camps and the like.

Space shuttle, the history of the National Space Transportation System : the first 100 missions

Elementary literacy lessons, cases and commentaries from the field

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Are the trees in bloom over there?, thoughts and memories of two brothers

Spinoff 2005