Word: cm
(lookup in dictionary)
(lookup stats)
Dates: during 1971-1971
Sort By: most recent first
(reverse)
...other formidable problems in communicating with an alien race. At what frequency would a civilization listen for and transmit messages? Many scientists have proposed the 21-cm. band, which is the wave length of emissions from the hydrogen atom, the most abundant element in the universe. Another hurdle might well be the choice of a language that would be universally understood by intelligent beings (see diagram, page 56). Also, because man has so recently entered a technological state, any civilization capable of receiving earthly signs might be far more sophisticated. Would it bother to reply? Possibly not, according to Sagan...
...Cornell Astronomer Frank Drake, Electrical Engineer Bernard Oliver composed a sample universal message that could conceivably have been sent from some distant planet. The information would be contained in a series of irregularly spaced pulses picked up by radio telescopes tuned to a wave length of 21 cm. (the natural frequency of radiation from a hydrogen atom and an obvious choice of an advanced civilization). Translated into print, the message would consist of an apparently meaningless sequence of 1,271 ones (for pulses) and zeros (for gaps between the pulses...
...that the alien race has six-fingered hands. Finally, the bracket at the lower right seems to measure the height of the adults and is labeled at mid-point by the binary number eleven. Because the only length that the senders and receivers know in common is the 21-cm. wave length of the transmitted signal, it can be assumed that the adults are eleven of those wave lengths, or 71 ft. tall...