Word: asteroids
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Dates: during 1950-1959
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...seas are really flat, low plains filled with dust or lava. They must have been formed rather late in the moon's history, because few meteor craters pit their surfaces. Astronomer Gerard Kuiper of the University of Chicago thinks that the seas were made by the impact of asteroids up to 90 miles in diameter, which blasted great holes in the crust at a time when the moon's interior was hot and plastic. Dark lava welled up in the holes, and is visible there today. Kuiper thinks that the shock of the last big asteroid, which...
Both systems must exert their influence while the missile is still in the atmosphere or the motor is still thrusting. In space, with the rocket cold, a ballistic missile is as independent as an asteroid. But another guidance problem remains. The missile ascends toward space nose up and cruises toward its target around the curve of the earth. Thus, in natural flight it will re-enter the atmosphere more or less broadside on. This is undesirable; so a "positioning device" must be provided to turn its nose toward its target. There are several possible ways of doing this, such...
...rocket ship is to avoid collisions with meteors, said Dr. Fred L. Whipple, chairman of Harvard's department of astronomy, it should keep pretty well out of the orbits of the earth and the comets, and particularly try to detour around the asteroid belt between Mars and Jupiter. But a collision with a meteor won't necessarily be fatal. "Most penetration," said Dr. Whipple, "could be eliminated by a 'meteor bumper,' a second skin of small thickness a short distance outside the true skin of the ship. Meteorites would explode on that bumper and lose most...
...Protests or not, the name actually stuck. Mr. Hoover may be glad to learn that he is still on Olympus-and that Hooveria, usually called an asteroid, still circles in the sky, about midway between Jupiter and Mars...
Collisions between two small objects (asteroid size or less) are probably quite frequent, and in such cases there is no atmosphere and little gravity to keep dust particles from wandering off on their own. It is mostly these small encounters in the solar system's gravel mill that keep the zodiacal light shining faintly...