Science Sunday 05-28-18

A Brief History of Flight – The Space Age – Part 2

Apollo 11

On July 20th of 1969, an event of epic proportions took place.  Two American astronauts, Neil Armstrong and Buzz Aldrin, landed their lunar excursion module (LEM) Eagle on the Moon, fulfilling the first part of President Kennedy’s challenge in 1961 that the United States “should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely.”

A third astronaut, Michael Collins stayed in orbit around the Moon in the command module Columbia, their return ticket to Earth.

It had taken them a little over 4 days to get to the Moon, leaving on July 16th.  Armstrong and Aldrin would stay on the Moon less than a day.  They would return to Earth in less than 3 days, successfully splashing down in the Pacific Ocean about 800 miles southwest of Hawaii, thus fulfilling the second part of President Kennedy’s challenge.

Even now, 48 years later, it is hard to conceive of the courage these three men would have to summon up, to sit on top of the (still) world’s largest rocket, the Saturn V, and blast off to the Moon.  They were still attached to the final stage of the rocket when it ignited, sending them into the translunar injection orbit (TLI) they needed to rendezvous with the Moon 4 days later.

When they first orbited the Moon, and were out of radio communication with Earth, the entire world held its collective breath.  Would the astronauts make it around the Moon and return to radio communication, or would they die on the far side of the Moon, which never presents itself visually to Earth?

When Armstrong and Aldrin landed on the Moon, in the Sea of Tranquility, between 500 and 600 million people on Earth watched from every corner of our planet.  It was a truly mesmerizing moment.

Although their stay was quite short, Armstrong and Aldrin planted the American flag there, set up a “Moon quake” seismograph, and installed a mirror to reflect laser beams from Earth so as to measure the Earth-Moon distance to within a quarter of a millimeter.

Both the landing and the blastoff (from the Moon) of the LEM were not without difficulty.  On landing, Armstrong could see that the computer driven LEM landing was going to miss its ideal landing spot, and place the craft in a rock strewn area.  He took semiautomatic control of the craft and landed it safely.

On departure, one of the switches needed for the LEM blastoff was broken, but the astronauts fixed the problem with a pen.  The blastoff knocked over the flag they have carefully positioned on the Moon.

Once docked with Columbia, the LEM was detached.  It would orbit the Moon on its own for a few additional months.

Columbia splashed down upside down, but inflatable balloons quickly righted the capsule.  The Apollo 11 astronauts had managed to bring back a little less than 50 pounds of lunar rocks.

After being quarantined for a good three weeks, the Apollo 11 astronauts returned to civilization with great acclaim, enjoying ticker tape parades in New York and Chicago.

As of this writing, both Aldrin and Collins are still alive, but Armstrong died in 2012.

There were seven Apollo missions, resulting in six successful landings.  Only Apollo 13 had to turn back because of damage to the command module Odyssey.

All in all, 12 men landed on the Moon, all returning successfully to Earth.  Four survive, with Apollo 12’s Alan Bean just recently passing.