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A Science Odyssey Title 'A Science Odyssey: 100 Years of Discovery' Title

Excerpt from Chapter One, "Mysteries of the Universe"

Objects Strange and Wonderful, Page 1 of 5

Ironically, just as the existence of life on earth seemed more tenuous than ever, there appeared hints of previously unknown forms of matter, or even life -- thanks to an expanding array of methods of "looking" ever farther into uncharted space. During the war radar operators were annoyed by strange interference from outer space, but they had more immediate matters to deal with. Discovered in 1931, radio astronomy developed in peacetime, along with X-ray and ultraviolet astronomy, as a new way of investigating space and time. Although celestial objects radiate all the wavelengths of the entire electromagnetic spectrum, only radio and optical waves travel into human ken. The radio astronomer does not look through an eyepiece, of course, but waits for a computer to process distant radio waves and plot them on a graph. An antenna picks up the signals and converts them to electrical output, which is then amplified for storage on magnetic tape or for real-time display. The signals are almost undiscernibly weak after their voyages across light-years of curved space; according to one estimate, the total amassed by all radio astronomers to date would not provide enough energy to illuminate a flashlight for even a millionth of a second.


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