This Day in Geek History: August 5
At 2:45am, the first telegraph message sent via undersea cable is transmitted from Trinity Bay, Newfoundland to Valentia, Ireland over the first transatlantic cable at a rate of approximately four words per minute. The project’s supervising engineer, Charles Bright, will later be knighted for the achievement.
Giovanni Batista Donati makes the first spectroscopic observations of a comet tail using the small comet, Tempel, 1864 II. He discovers that, at a distance from the Sun, the spectrum of a comet is identical to that of the Sun, because its visibility is only reflected sunlight. Donati demonstrates that a comet tail formed close to the Sun contains luminous gas. In the spectrum of light from the comet tail, Donati discerned three absorption bands superimposed on a continuous spectrum, which he designates as alpha, beta, and gamma.
The first electric traffic light systems are installed in Cleveland, Ohio.
Britain, America, and Russia signed a Limited Nuclear Test Ban Treaty in Moscow to prohibit nuclear weapons tests “or any other nuclear explosion” in the atmosphere, in outer space, or under water. The treaty allows for underground testing, but it stipulates that such tests may not cause “radioactive debris to be present outside the territorial limits” of their own nation. A total of one hundred eight countries will sign the LNTB Treaty before it goes into effect on October 10, 1963.
The NASA space probe Mariner 7, which had been launched Mar 27, 1969, passes within 3,430km of the surface of Mars. During the course of the fly-by, the probe takes twenty-two images spanning twenty percent of the planet’s surface. These photos will prove that the surfaces of Mars and the Moon are very different. These photos are taken in addition to the ninety-three far-encounter images the probe has taken on its approach. Other instruments take atmospheric measurements, and revealed that the south polar ice cap’s composition is mostly frozen carbon dioxide. The probe’s radio telemetry also provides improved estimates of the planet’s size, shape, and mass.
The USSR launches Mars 6 orbiter. Upon reaching Mars on March 12, 1974, its descent module will detach to study the atmosphere and surface of Mars. The descent module will transmit 224 seconds of data, which will be relayed by its flyby module, back to Earth, becoming the first data ever returned from the atmosphere of the planet. Unfortunately, much of the data will turn out to be unreadable because of a malfunctioning computer chip. The data will include pressure, temperature, and water vapor readings.
Mira-Pak Inc. settles its antitrust suit against International Business Machines (IBM). In 1973, Mira-Pak alleged that IBM had monopolize the market for computers to control the weight of snack food packaging.