Lost in Space? - Don't Know Much About Geography - page 163

Of course, this is theory and not everyone agrees. Many paleontologists accept the possibility of such
an impact but refute the notion that it caused mass extinctions. One reason is that so many other animal
forms alive at the same time were able to survive the conditions.
This is an interesting scientific parlor game that might be resolved before long. But it still leaves the
question of whether it can—or might—happen again. To date, no person or animal has been killed by a
meteorite—except for a dog hit by a meteorite in Egypt in 1911. If you are the gambling type, this question
is all about playing the odds. The NASA team investigating the possibility found those odds slim but not
negligible. They judged that the chances of an asteroid capable of inflicting serious global damage might
hit the earth once in every 500,000 years. According to one estimate, that means for a person living sev-
enty years, the chances of seeing the earth in upheaval as the result of an asteroid strike are 1 in 7,000. By
comparison, the risk of death by automobile accident is much greater—1 in 100—but the risk of death by
airplane crash is 1 in 20,000. As the old saying goes, “You pays your money and you takes your choice.”
Milestones in Space Exploration
1919 American scientist Robert H. Goddard (1882-1945) publishes a paper, A Method of Reaching
Extreme Altitudes , that suggests sending a small vehicle to the moon using rockets. When it is
widely dismissed in the press, Goddard decides not to expose himself to further ridicule. His ideas
are ignored by the U.S. government but attract great interest in Germany.
1926 Robert Goddard launches the first liquid-fuel-propelled rocket.
1929 American astronomer Edwin Hubble (1889-1953) establishes that the more distant a galaxy
is, the faster it is receding from the earth. Known as Hubble's Law, this discovery confirms that the
universe is expanding.
1930 The planet Pluto is discovered.
1938 Germany's liquid-fueled-rocket experiments, under the direction of engineer Wernher von
Braun (1912-77), succeed in producing a rocket that can travel 11 miles (18 km). In 1944, improved
models of these rockets are being used as the V-1 and V-2 self-propelled bombs launched against
England in WWII. After the war, von Braun is brought to the United States and leads the develop-
ment of the American rocket program that ultimately puts a man on the moon and conceives the
space-shuttle concept.
1939 American physicist J. Robert Oppenheimer, who later headed the Manhattan Project that de-
veloped the atomic bomb during World War II, works out a theory of “black holes.” Oppenheimer
calculates that if the mass of a star is 3.2 times the mass of the sun, its collapse, caused by lack of
internal radiation, would result in all the star's mass being reduced to a single point.
1949 A rocket-testing ground is set up at Cape Canaveral, Florida.
1957 The first space satellite, Sputnik I , is launched by the USSR in October. It is followed that year
by Sputnik II , containing a live dog.