Word: hydrogen
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Dates: during 1970-1979
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...Interest. Nuclear Pioneer George Weil agrees, calling the breeder concept "dangerous and unproved." Some objections focus on the use of liquid sodium (a tricky substance that explodes on contact with water and burns in air) as a cooling medium. Others concern the fuel, plutonium, the basic ingredient of the hydrogen bomb and one of the deadliest substances known. Finally, the critics wonder how to get rid of radioactive wastes from any nuclear reactor, some of which remain lethal for 500,000 years. At present, the AEC plans to store them in large concrete containers at an as yet unspecified location...
Research Laboratory, the astronauts took ultraviolet pictures of the clouds of ionized (charged) hydrogen gases that occupy the vast regions between the stars. These observations, which may offer new clues to such questions as how stars are formed, cannot be made from earth where the atmosphere blocks ultraviolet light. In addition, at a number of their stops, the astronauts took careful measurements to augment data about the moon's magnetic field, which analysis of moon rocks shows was once surprisingly strong; the strong field, in turn, suggests that the core of the moon was once molten. Aboard Casper, high...
...wife, Linda, an artist-chose figures of two representative earthlings (see A in diagram). Their height is indicated by the scale drawing of Pioneer in the background (B). The message contains a more subtle dimensional clue (C) that an extraterrestrial physicist should quickly recognize: an atom of hydrogen, the most abundant element in the universe, which is shown undergoing a change of energy state (indicated by the different orientations of the orbiting electrons on the circles). During this process, the atom gives off a pulse of radiation with a wave length of 21 cm., which is also the message...
...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...
...assuming that the number opposite the first planet is one, the second planet two, and so on, scientists can spot the alien binary code. Giving their imaginations free rein, they can also recognize that the three groups of dots to the right of the star represent atomic diagrams: hydrogen (with one electron circling a central nucleus), carbon (six electrons and a nucleus) and oxygen (eight electrons and a nucleus). The atoms chosen suggest that life on the distant planet is based on a carbohydrate chemistry...