Word: doppler
(lookup in dictionary)
(lookup stats)
Dates: during 1940-1949
Sort By: most recent first
(reverse)
...Signal Corps repeated the experiment many times, and disinterested scientists checked the results. Sample check: the echo wave at moonrise-when the first contact was made-was slightly higher in frequency than the outgoing pulse. In accordance with the Doppler Effect, a wave reflected from an approaching body must increase its frequency. Chiefly because of the earth's revolution, the moon at that hour was moving toward the sending station at about 750 miles an hour...
...various elements and compounds can be identified. Light from Mars comes through the earth's air blanket, which contains water vapor, so Dr. Adams had to separate the terrestrial vapor pattern from the Martian (if any). This he did with the help of a phenomenon called the Doppler effect: when a source of light approaches earth, its spectrum lines are shifted to the right, and when it is receding they are shifted to the left. At times when Mars is fast approaching or retreating, the Doppler effect should pull the Martian vapor lines away from the earth lines enough...