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Saving the Apollo 13 Mission
On April 11, 1970, Apollo 13 was launched for a planned moon landing. Two days into the mission, however, one of the oxygen tanks in the spacecraft exploded, causing a loss of air, electricity, and water. The moon landing had to be canceled, and the astronauts had to figure out how to get home. Their solution was to move into the lunar module, the small craft that was supposed to land on the moon, for much of the remaining trip. The lunar module contained fewer supplies, however. Therefore, the astronauts had to conserve as much food and water as possible. By firing the lunar module's engine, the men were able to get the spacecraft on the correct course to return to Earth. On April 17, Apollo 13 landed safely in the Pacific Ocean.
What is the main, or central, idea of the passage?
The main, or central, idea of the passage is the story of how the Apollo 13 mission faced a crisis when an oxygen tank exploded, resulting in the cancellation of the moon landing, and how the astronauts successfully managed to conserve supplies and maneuver the spacecraft back to Earth safely.
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The Missing Patent
Wilbur and Orville Wright's official patent for their "flying machine," submitted in 1903, is an important slice of American history. The patent was supposed to be stored in the National Archives, where historical treasures are housed. However, in 2000, officials discovered that it seemed to have vanished. Researchers looked through storage vaults, filing cabinets, and archives around the country, to no avail. Some wondered whether the document had been stolen. Finally, Chris Abraham, newly assigned to the National Archives' document recovery program, volunteered to solve the puzzle. Abraham suspected that the patent might have been mistakenly sent to a huge storage facility in Kansas where other, less important patent documents were kept. Abraham was right: after searching through boxes and boxes of documents, he found the patent on March 22, 2016.
What is the main, or central, idea of the passage?