Word: dopplered
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...accelerate gradually, keeping their speed fairly low while still in the atmosphere, then spurting quickly. If a rocket is moving 24,000 m.p.h. when it is 300 miles above the surface, it will escape from the earth's gravitation. When the Russian Lunik launchers, watching their bird with Doppler (speed-measuring) radios, saw it pass the critical speed, they knew it would never return to earth. A lesser speed than escape velocity sets a satellite revolving around the earth just free of the atmosphere. A satellite can be compared to a chip or leaf circling around the sides...
...from Helsinki: "The state radio here picked up signals early today which indicate Russia may have launched a moon rocket." European radio stations, said U.P., had picked up a "mysterious beep-beep-beep" which lasted three times as long as the signal from an orbiting Sputnik and "suggested the Doppler effect* that would be produced by a transmitter speeding away from the earth...
...According to the scientific principle named for Austrian Physicist Christian Johann Doppler (1803-53), the speed of an object moving toward or away from the observer can be accurately measured by changes in the length of the radio waves it transmits...
...electronic apparatus that transmits to the ground two narrow beams of microwaves. When the waves hit the ground, a small part of their energy is reflected back to the transmitter. If the transmitter is moving, as in an airplane, the frequency of the waves is changed slightly by the Doppler effect.*The amount of the change, which can be measured with gnat-hair accuracy, gives the speed of the airplane...
During the night Astronomer Meinel made two exposures. The first was enough: the plate showed bands representing the special wave lengths of light emitted by electrically excited hydrogen atoms. The big news was that the bands were not sharp, but smudged. This proved (by the "Doppler effect")*that some of the light was coming from fast-moving objects: i.e., hydrogen particles racing toward the earth from the sun. A rough calculation gave their speed as about 1,800 miles per second -about the right speed for a 15-hour journey from the sun to the earth's upper atmosphere...