After Apollo 13's near disaster, the fate of the lunar program was back on rocky ground.
Apollo 14 was scheduled to launch before the end of the year and it would provide the most
extensive scientific exploration yet,
but if it was ever going to take off,
investigators needed to determine what exactly went wrong on Apollo 13.
And NASA had to make sure that it wouldn't happen again.
The investigation found that the near-disaster was a combination of
human and design error.
The source of the explosion was an oxygen tank inside the Service Module.
Before it made it onto Apollo 13, the tank went through a series of problems.
In 1968, it was scheduled to fly on Apollo 10
but was accidentally dropped on the ground before the mission.
After it passed a series of tests, it was cleared to fly on Apollo 13.
But then, in 1970, during pre-flight testing, the tank wasn't emptying as it should.
So, to gasify the liquid oxygen, technicians turned on the tank's heater using 65 volts
which should have been fine since the spacecraft components were all modified
to handle increased power in 1965.
But unfortunately, the thermostatic switch within the oxygen tank
was still geared for just 28 volts.
It was later found that the excess power caused the switch to weld shut, and the temperature
inside the tank rose to over 500 degrees Celsius and damaged insulation on the wires inside
the tank, leaving a high risk for a short circuit.
From the outside, though, everything appeared to be... good enough to fly.
So on April 11, 1970 Apollo 13 essentially lifted off with a time bomb inside the service module.
After the near disaster, NASA had to make major structural changes
to the Command-Service Module and the Lunar Module.
Improvements were also made to the astronauts airtight spacesuits
and the lunar surface experiment equipment.
Apollo 14 would be the first crewed mission to put these upgrades to the test.
NASA selected Astronaut Alan Shepard as the mission's commander.
Almost ten years prior, Shepard became the first American in space during Project Mercury.
Apollo 14 would mark his triumphant return after a rare disease
kept him grounded for many years.
Joining Shepard, were rookies Edgar Mitchell and Stuart Roosa.
About nine months after Apollo 13, NASA was headed back to the moon.
Apollo 14 was en route to the Fra Mauro formation - a ridged region that was believed to be
made up of an ejecta blanket from a collision between a huge mass and the Moon.
This made it an ideal landing location for science.
But getting there wasn't as smooth as NASA hoped.
Once in lunar orbit, it took six attempts before the crew could dock the Command and Lunar Modules.
And then during the descent to the Moon, the lunar module signaled an abort.
Mission control and the astronauts worked through the problems though, and the crew eventually
pulled off a high precision landing within target range.
On the surface, Shepard and Mitchell attempted a trek to the rim of the Cone Crater, collecting
lunar rocks in their space wagon along the way.
They also measured the strength of the Moon's magnetic field, collected samples of the solar
wind and studied the properties of lunar soil.
Additional experiments were deployed that enabled scientists to monitor activity from Earth.
Some of these experiments would go on to detect lunar "moonquakes", providing information
about the internal structure of the Moon.
And others would study the lunar ionosphere and measure the precise distance
between Earth and the Moon.
Back on the CSM, Roosa conducted orbital science activities that measured regional variations
in the Moon's gravitational acceleration and the scattering of radar waves from the lunar surface.
Apollo 14 packed in more science than any mission before it,
pushing the astronauts to new extremes.
They collected over 40 kilograms of rocks and soil from the lunar surface including
this one nicknamed "Big Bertha."
And Shepard, the oldest man to get to the moon, set a new distance-traveled record on
the lunar surface equivalent to about 55 laps in an Olympic-sized pool.
But aside from the extensive experiments and massive terrain covered, Apollo 14 is best
remembered for this moment when Alan Shepard broke out a modified six iron and hit two
golf balls into the cosmic distance.
The astronauts then headed back to the CSM to begin their return to Earth.
Apollo 14 has a longstanding legacy linked to discovery.
The lunar samples returned have been studied for decades, helping scientists better estimate
the age and physical nature of the moon.
Photos from the mission verified the role of volcanism in the formation and modification
of lunar highlands and documented deep-space phenomena known as Zodiacal light and Gegenschein.
Seeds that were aboard the mission were planted around the world and have since grown into
living monuments of the third trip to the Moon.
Apollo 14 also validated the changes NASA made after the Apollo 13 disaster and demonstrated
that spaceflight challenges are solvable.
The next missions would build off this momentum, taking exploration capabilities
even further with the introduction of a new way for astronauts to explore the lunar surface.
If you want to learn more Apollo 13 and how NASA got the astronauts home safely,
check out this video.
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