- [Jared] The year 2019
marks the 50th anniversary of the Apollo 11 moon landing. Let's celebrate by using 3D animation to show the inside of
the Apollo Lunar Module. Let's check it out. (electricity buzzes) (explosion pops) All right, so we're
gonna land on the moon. What should our landing vehicle look like? Early artwork got their
ideas from science fiction. Then, we started building prototypes. This one had five legs. Our astronauts will want to see outside, so let's make a cockpit with some windows. (soft music) The final design has only four legs, and the windows are much
smaller to save weight. It was about 23-feet tall. For comparison, here's
the size of a person. The LM was designed and
built in Bethpage, New York, by the Grumman Corporation. It took hundreds of engineers and most of the 1960s to complete. It was originally called the Lunar Excursion Module, or just LEM. Eventually, the word excursion
was dropped from the acronym, but everyone still
pronounced it the same, LM. It was a long process to get this machine all the way to the surface of the moon. It was launched aboard the Saturn V rocket and then went to the moon along with the Service Module
and Command Module. These three parts together are what we call the Apollo Spacecraft. The LM was the only part that goes down to the surface of the moon. It was the first spacecraft designed to only operate in the vacuum of space. So for example, the Command Module needed to be really aerodynamic for the launch through the earth's atmosphere. The LM wasn't exposed until
it was in outer space. Since there's no air up here, the outline really doesn't matter. This is part of why you get a spacecraft that looks unlike anything
we've seen before. Starting with the famous Apollo 11, there were a total of six moon landings covering a span of about three years. Apollo 13 had an accident in space and was forced to come home early without landing on the moon. Earlier missions tested the
lunar module in earth orbit, and then once in lunar orbit without actually landing on the moon. More Apollo missions were planned but were canceled due to budget cuts. The LM was split up into two parts: the ascent stage and the descent stage. For the landing, both parts
went to the surface of the moon. When it's time to leave, only the ascent stage leaves the surface, which means that each of
the Apollo moon landings left behind a descent stage. Let's zoom in for a closer look. There were four legs attached to the side. These were originally in
the retracted position so that the limb would fit
into the Saturn V for launch. Then, once they are getting ready to land, the legs are extended. Three of the legs contained
a contact-sensing probe, which told the astronauts
that they were close enough to the surface to shut
off the descent engine. This leg has the ladder which
the astronauts can climb down. On the left side of the ladder, there's a container which
holds the American flag. The shape of the descent stage
is somewhat of an octagon. Here's what the structure
looks like underneath. Inside there were five
box-shaped compartments. The center one contained the decent engine which was used for landing on the moon. In order to light this engine up, we'll need two oxidizer
tanks and two fuel tanks. They both feed right into the engine. This gives us the propulsion we'll need to safely land on the moon. These outer areas are where
they stored more equipment. They called them quadrants. So this was quadrant one,
two, three, and four. Quadrant one was for general storage. For the last three Apollo missions, there was the Lunar Roving
Vehicle packed inside of here. Once on the surface, it was
unpacked and ready for use. This allowed them to explore much further from the lunar module. Quadrant two contained a water tank, and then below here was the Apollo Lunar Surface
Experiments Package, or ALSEP, which basically contained
several science experiments for them to perform. Quadrant three had another
helium tank, oxygen tank, and on a few missions it
carried retroreflectors, which is a special kind of mirror. They were left behind on
the surface of the moon, and they allow scientists even today to balance laser light from
the earth to the moon and back. Quadrant four contained the Modularized Equipment
Stowage Assembly, or MESA. And if you've ever
wondered how we recorded those first few steps on the moon, there's a camera here that
points right towards the ladder. The landing legs were attached
on the main structure. The covering on the outside
was made out of Mylar, which looks like gold tinfoil. They used it because it was lightweight and it made sure that the
inside temperature didn't get too hot or too cold. This the platform that
leads to the ladder, and these are the plume deflectors. They protected the spacecraft from the thrusters on the ascent stage. We'll talk about that later in the video. Before we look at the ascent stage, I want to thank Audible for
sponsoring today's video. Not everyone has time to sit
down and read a physical book, but Audible allows you
to listen to audiobooks while you go about your day. One audiobook that helped
me create this video is Neil Armstrong: A Life of Flight. It tells the story of the
first man to walk on the moon and the different life
events that led him there. And yes, it's available
to listen to on Audible. If you're ready to sign up
and help support my channel, visit Audible.com/JaredOwen
or text jaredowen to 500 500. It's only 14.95 per month. However, for the month of July only, Amazon Prime members can
start and Audible membership and get three months for only 4.95. That's three months for the price of one. After that, it's only 14.95 per month. Visit Audible.com/JaredOwen or text jaredowen to 500
500 to get started today. Okay, let's take a look
at the ascent stage now. If we remove the cover, you can see some of the
machinery underneath. Let's start with the main structure. This is the crew compartment, the midsection, and the aft equipment bay. Both the crew compartment
and the midsection were normally pressurized, which means that they can safely
take off their spacesuits. The crew compartment
didn't have a lot of room. Controls were mostly in the front, and then there's two windows to look outside at the
surface of the moon. The commander was on the left, and the LM pilot was on the right. Remember, that the third astronaut was still orbiting the moon in the CSM. After landing, this hatch
is for the astronauts to leave the cabin and start
their climb down the ladder. In the midsection, you'll
find more equipment and this cover which
protected the ascent engine. And of course, the tunnel to
dock with the Command Module once back in lunar orbit. The aft equipment bay has
more oxygen and helium tanks as well as other electronics for the LM. There's a fuel tank here and
a smaller oxidizer tank here. This is the reason that we have these bulges on the side here. Both of these tanks feed
right into the ascent engine which was used to blast off
the surface of the moon. On the outside is the Reaction
Control System, or RCS. It's an arrangement of 16
thrusters in groups of four. It was powered by fuel and
oxidizer tanks on the side here. During the flight, these
thrusters could be used to maneuver the LM. The plume deflectors helped redirect the exhaust to protect the descent stage. On the outside were several antennas to let them communicate with
Mission Control back on earth. So much effort went into
building each Lunar Module. What's sad here is that they
could only be used once. Most of the descent stages
are peacefully sitting on the moon, and most of
the ascent stages crashed into the moon after they were
discarded in lunar orbit. A few lunar modules never got
the chance to fly in space. They are now located in museums along the east coast of the United States. My name's Jared, and I
make 3D animated videos about how things work. Click here to learn more
about the Apollo Spacecraft, and click here to subscribe to my channel. Thanks for watching, and
I'll see you next time.
Videos like this just remind me what an act of technological vandalism the cancellation of Apollo was.