America's First Manned Flight

America’s First Manned Flight

The United States took its first small step toward the Moon on May 5, 1961. On that occasion, Alan Shepard became the first American to fly in space as he rode his cramped Mercury capsule to an altitude of 116 before splashing down in the Atlantic Ocean 302 miles from the Cape Canaveral launch pad.

Although Shepard’s flight was brief – about fifteen minutes – it represented a major technical and political breakthrough for the American space program. America needed a breakthrough to keep pace with the Soviet space program. Cosmonaut Yuri Gagarin became the first man to fly in space on April 12, 1961, completing one full Earth orbit.

Alan Shepard. Photo in public domain

In the meantime, the American program was floundering. Just ten days before Shepard’s flight an unmanned Mercury-Atlas vehicle was destroyed by ground controllers when it veered off course. With Gagarin’s triumphant orbital mission, the United States was forced to play catch-up once again.

NASA chose Shepard, a thirty-seven-year-old Navy Lieutenant Commander to make the first suborbital flight. His Freedom 7 spacecraft was lofted into space by a Redstone rocket booster. The Redstone ignited at 9.34 a.m. on May 5, 1961, and by 9.50, Shepard was bobbing atop the Atlantic waiting for the recovery ship USS Lake Champlain.

Shepard suffered no ill effects from his brief exposure to the space environment, setting the stage for longer orbital flights for years to come. More important, his mission gave President Kennedy John F. Kennedy the confidence to set a tough goal for the US space program. On May 25, the same year, Kennedy committed the United States to landing a man on the Moon by the end of the decade.

Science Fiction is not just about the future of space ships travelling to other planets, it is fiction based on science and I am using science as my basis for my fiction, but it's the science of prehistory - palaeontology and archaeology - rather than astronomy or physics (Jean M. Auel). Illustration: © Megan Jorgensen.

Astronomical Clocks

Astronomical clocks

In Western Europe the first mechanical clocks appeared during the first half of the fourteenth century. They were driven by a weight suspended from a drum, and controlled by a heavy bar, or “foliot”. Pivoted near its centre and pushed first one way and the other by a toothed wheel. The Chinese, however, had mechanical clocks long before this time. One particularly fine example, fully documented, was the 30-foot astronomical clock tower of Su Sung, built in 1080 A.D. In this case the motive power was provided by a turning water wheel, held in check by a weighbridge and trip levers.

A clock at 576 Sherbourne street. A modern clock at 576, Sherbourne street, Toronto. Photo: Elena

Most early mechanical clocks were designed to indicate the time by a hand or hands moving over a dial. But several had elaborate dials for showing astronomical events like the age and phases of the moon, and the position of the sun. Foremost among the latter was a remarkable clock designed by Giovanni de Dondi and made in 1364. This not only showed the time of day but also, through its complex system of gear wheels, the fixed and movable feast-days and the earth-centered motions and positions of the seven wanderers (the Greec definition of the sun, moon and five naked-eye planets).

By far, the most famous astronomical clock is the one in Strasbourg Cathedral, built between 1838 and 1842. It had two predecessors, the first completed in 1354, and the second in 1574.

TRW GROUP

TRW GROUP

In the early days of the Space exploration, TRW’s System Group was one of five operating units of TRW Inc. Along with its three sister groups – Automotive group, Equipment group, and Electronic group, plus industrial operations – it forms a large corporation that provided many different kinds of products and services to space, defense, aircraft, auto, electronics, and related industrial and commercial markets.

The larger whole of which TRW’s System Group formed a part was a giant international corporation – TRW Inc. Begun as a cap screw manufacturer in Cleveland, Ohio, at the turn of the XXth century, it employed 80, 000 people in the 1950s, maintained facilities in 13 countries, and had an annual sales volume well over $1 billion.

Nearly every engine manufactured in the US – from autos and jets to lawnmowers, – used TRW parts. Most color television receivers carried their electronic components. They manufactured grenade launchers and major subsystems for the MK 46 torpedo. Their cams, gears and bearings were used in a large proportion of automobiles and aircraft in the US and Western Europe.

Photo by Elena

TRW began in the early days of the ballistic missile crisis, providing systems engineering and technical direction on the Atlas, Thor, Titan, and Minuteman missiles. In addition to their headquarters facilities in Redondo Beach, the group had at that time major operations located at Houston, Washington D.C., and Cape Canaveral. They numbered some 16, 000 scientists, engineers, and support personnel, who applied advanced technology to some of the critical military, scientific, and socio-economic problems of our times.

Since the early days of its participation in the ballistic missile program, TRW designed and manufactured a variety of rocket engines for powering and controlling upper stage vehicles and spacecraft. One of their assignments included the design and manufacture of the Lunar Module Descent Engine, which safely landed Apollo astronauts on the surface of the Moon.

The TRW LM Descent Engine was assigned an extremely critical role: to launch an LM containing the two astronauts into a lunar transfer orbit (path which brought them directly to the lunar surface), then slowed their rate of descent from 3500 mph to zero at 200 feet above the lunar surface, and finally lowered them safely to a soft landing. To perform these tasks, it must be throttleable (capable of varying rates of thrust) – and, of course, it had to be very dependable. The LMDE was a pressure-fed, liquid be-propellant, gimballing (capable of swivelling so as to change the direction of thrust) rocket engine. It produced a maximum thrust of 10,000 pounds and was throttleable down to approximately 1050 pounds. The propellants, nitrogen tetroxide (N2O4) and a 50-50 blend of hydrazine and unsymmetrical dimethyl hydrazine, are hypergolic, – that is, they ignite upon contact with one another. Total weight of the engine without propellants was about 290 pounds.

Each of the two Mariner’ 60 spacecraft incorporated a TRW-built propulsion subsystem. The Mariner 6 engine was fired in February of 1969 at 750,000 miles from Earth, the Mariner 7 in April at 2 ½ million miles, precisely adjusting the trajectories of both spacecraft for accurate flights past Mars in July and August of 1969. The weight of Mariner 69 engine was of 45 pounds including propellant. It stood slightly over 3 feet high and was capable of two starts and fired at 50 pounds of constant thrust.

The TRW identity as System group was perhaps best indicated by a 16 x 31-feet mural called “The Quadrisciences” which was displayed in the administration building at Space Park. The mural symbolically depicted four areas of man’s quest for knowledge: the earth, the sea, near space, and deep space. The TRW’s goal at System group was to acquire and apply scientific knowledge in those four environments.

From space craft design and manufacturing to anti-submarine warfare, from building mid-course correction engines for the Mariner Mars spacecraft to evaluating methods of high-speed ground transportation, from designing electronic warfare devices to developing plans for solving such pressing social problems as water and air pollution, overcrowded medical facilities, and ineffective community services – in short, in all for environments of Quadrisciences – the TRW expanded the frontiers of basic research in order to build a better world.

One example of electrical propulsion research at TRW: They developed an engine, a colloid microthruster, under contract to the Air Force. During the first 500-hour firing it produced 32 micro-pounds of thrust and 1SP of 1200 seconds. Engines like this, which have ISPs in the range of 800-1500 seconds and operational life expectancies of thousands of hours, are useful for such tasks as stationkeeping (keeping a spacecraft in the correct orbit), and attitude control (keeping a spacecraft pointed in the right direction). That engine weighs only 8-3/4 pounds together with a 5-watt electrical power unit.

Planetariums

Planetariums

A historical survey

Clocklike Gearing

Strictly speaking, a planetarium, as the name suggests, is a device that can be used to demonstrate the motions of the seven Greek “planetes” or “wanderers”, namely, the sun, moon and five naked-eye planets. A device of this kind involves the use of clocklike gearing, or at least, a system of pulleys, but it need not rely on some form of optical projection.

If we accept this definition it is a fairly easy matter to trace the development of the planetarium. We can, for example, include all models of solar system, consider astronomical clocks, and in fact, identify the origin of the planetarium with that of mechanical clock. The latter, as Derek Price and other historians have pointed out, grew out of the use of toothed wheels to transmit power, and not. As is commonly supposed, from sundials, sand-clocks and water-clocks.

Ancient Toronto Planetarium.

Archimedes’ Planetarium

An early example of the use of gears to provide power transmission and at the same time give special ratios of angular movement, is the planetarium said to be constructed by Archimedes in the third century B.C. The device was described by Cicero and several later authors, but unfortunately the accounts contain no technical information. As far as we can tell it took the form of a hollow metal globe presumably of a lattice construction , with a small model earth at its center.

According to Cicero, who got his information from C. Sulpicius Gallus, “a very learned man”, the globe could be rotated, so that the seven wanderers went through “various and divergent movements with their different rates of speed.” Ovid described it as a “miniature representation of the vast vault of heaven”.

Astrolabes

The planetarium of Archimedes could have been similar to an armillary sphere or spherical astrolabe, an instrument introduced by ancient Greeks for determining the positions of the seven wanderers relative to the stars. At first it consisted of a few graduated, concentric, and intersecting rings which represented the horizon, meridian, celestial equator, and ecliptic, but after the fifteenth century it became more elaborate. One development was to add further reference circles and to fix a model earth in the middle. Another was to add moving models of the seven wanderers, so that the whole affair illustrated the earth-centered or Aristotelian conception of the universe. Yet another was to turn it into a flat of planispheric astrolabe, in which form it was widely used by the Muslims as an aid to navigation. Many of these flat astrolabes are now preserved in museums. They are beautifully constructed and often bear exquisite designs. The men who made them were not only technicians and craftsmen but also great artists.

Antikithera Machine. Fragments of the Antikythera Machine. An early form of planetarium instrument

Some astrolabes had a built-in system of gear wheels and served as elaborate astronomical computers. They may have an early representative in certain corroded pieces of bronze gear-wheels salvaged in 1901 from the wreck of an old ship found off the island of Antikythera, between Greece and Crete. The parts, believed to date from about 65 B.C., were accompanied by traces of what may have been a wooden case. They also carry partly legible inscriptions, and these, along with the partial reconstruction of the gears, indicate that the machine was in early form of astronomical computer.

Rebirth of America’s Manned Space Program

Rebirth of America’s Manned Space Program

The Beginning of a New Era

The rebirth of America’s manned space program happened in March, 1981. The space shuttle Columbia, carrying astronauts John Young and Robert Crippen, began its maiden voyage on April 12, 1981, twenty years to the day after Soviet cosmonaut Yuri Gagarin became the first human to fly in space.

Columbia’s fifty-four-hour mission was the first manned American space flight since the US/USSR Apollo-Soyuz mission six years earlier. The flight produced one of the most enduring images of the entire shuttle program: an almost giddy John Young pacing beneath Columbia after guiding it to perfect landing in California, smiling and gesturing like a schoolboy on the first day of summer.

Supernova Remnant Cassiopeia A. Source of the image: http://gallery.spitzer.caltech.edu/Imagegallery/image.php?image_name=ssc2005-14c. Authors: Oliver Krause (Steward Observatory) George H. Rieke (Steward Observatory) Stephan M. Birkmann (Max-Planck-Institut fur Astronomie) Emeric Le Floc’h (Steward Observatory) Karl D. Gordon (Steward Observatory) Eiichi Egami (Steward Observatory) John Bieging (Steward Observatory) John P. Hughes (Rutgers University) Erick Young (Steward Observatory) Joannah L. Hinz (Steward Observatory) Sascha P. Quanz (Max-Planck-Institut fur Astronomie) Dean C. Hines (Space Science Institute)

In the decade since Columbia’s inaugural flight, the shuttle fleet has played a major role in the space science. In April 1984, for example, shuttle astronauts repaired the crippled Solar Maximum Mission satellite. By replacing some of the electronics onboard the large satellite, astronauts brought Solar Max back to life, allowing it to collect important data on the Sun until it tumbled to Earth in 1989.

Telescopes carried into orbit by the shuttle have studied the Sun, examined objects that emit much of their energy in the infrared and ultraviolet regions of the electromagnetic spectrum, and scanned suspected black holes. In 1990, the shuttle-launched Hubble Space Telescope opened an entire new window on the universe.

Shuttle orbiters also have served as launch platforms for two planetary space craft. Magellan, which is using a high resolution radar to map the surface of Venus, was deployed in May 1989. The Jupiter-bound Galileo spacecraft was launched five months after Magellan, and arrived at the giant planet in 1995.