Word: photons
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Among the instruments it carried to study the threshold of space were: 1) photon counters to detect X rays from the sun; 2) a spectrograph to record the sun's ultraviolet rays; 3) special photographic emulsions to trap cosmic rays, which are to be found at full power only above the atmosphere...
...shortest time that physicists are likely to mention nowadays is a ten-thousandth of a millionth of a millionth of a millionth of a second (i.e., 10 23 sec.), which is about the time it takes a photon (corpuscle of light) to traverse the diameter of an atomic nucleus, but there seems little prospect of ever being able to measure...
...critics question the "red shift" as a measure of velocity. The usual explanation of the reddening effect is that the luminous body's motion away from the observer "pulls out" the light waves, making them longer (redder) than normal. But since red light contains less energy per unit (photon) than violet light, Bubble's critics suggest that light may lose some of its energy in traversing space, thus turning redder. It may start out from a distant nebula as young, vigorous violet and arrive at the earth after millions of weary years as old, tired red. If that...
...Work. Imbedded in Max Planck's Law of Radiation (published in 1901) was something vastly more important: Planck's "universal constant" (6.624 x 10 -27 erg-seconds), now considered one of the three fundamental figures in the universe.* Planck's constant enabled Einstein to conceive the "photon" (particle of radiation). It also made possible Niels Bohr's model of the atom. It turned up in spectroscopy, in the study of X rays, in electronics. Upon it is based the whole science of quantum (wave) mechanics...
...photon (smallest unit of radiant energy) is equal to the frequency of the wave multiplied by Planck's constant h (6.55 X 10(-27)erg-seconds...