SciShow is supported by Brilliant.org.
[♪ INTRO]
It took nearly a decade of work and
billions dollars for Neil Armstrong and
Buzz Aldrin to walk on the surface of the Moon.
But you know what happened
after those first historic steps?
They went back inside the lander.
Only two and a half hours later.
And in that time, neither of them even walked
more than 100 meters from the lunar lander.
To do more science, future astronauts would
need to travel faster, go farther, and carry more.
And to do that, they needed to stop being
moonwalkers and become moondrivers.
Fortunately, NASA had just the
tool for them: the Moon buggy!
Okay, technically it was called the
Lunar Roving Vehicle, but c’mon.
The Moon buggy helped
astronauts on Apollos 15, 16, and 17
do more science and bring back
more samples than earlier missions.
And along the way, we built a really cool car.
Engineers had actually been thinking about
how to build a lunar rover since the
early 1960s, but those first
concepts were totally different.
Some engineers imagined heavy duty,
fully-enclosed vehicles
that also gave astronauts
a place to sleep and work.
Which was nothing like the final design.
By the time the Saturn V rocket was actually flying,
it became clear that there would
be almost no weight to spare,
so the plans had to be scaled down a bit.
In 1969, the final contract
was approved by NASA.
Then, the rover was put together
by Boeing and General Motors.
It was built of aluminum alloy,
weighed just 210 kilograms,
about a sixth of a modern-day compact car,
and had to fold in half to fit
beneath the lunar module.
But it was also sturdy,
and could carry 490 kilograms,
more than twice its weight and enough for two
astronauts, their tools, and a bunch of moon rocks.
It even had space for some nice amenities,
like seat belts, an armrest, and fenders.
So it was no Rolls-Royce.
But considering that it was a car on the Moon,
it was pretty impressive.
The first Apollo missions had
shown that the Moon’s soft,
powdery surface could make for uneven footing.
So the Moon buggy had not only four-wheel
drive, but four engines, one for each wheel.
Each produced only about 190 Watts of power,
or about a quarter horsepower,
but the Moon’s low gravity meant that
that was good enough for a top speed of about
13 kilometers per hour.
The lunar roving vehicle also carried what
might have be the world’s first dashcam,
a TV camera controllable from Earth.
That not only enhanced the PR value of later
missions, but allowed scientists at mission
control to look for interesting features as
the astronauts drove around.
Still, even that wasn’t the most
impressive piece of equipment on board:
The Moon buggy also carried a
revolutionary navigation computer.
Since the Moon doesn’t have a
magnetic field to move a compass needle,
and since surface maps didn’t have much detail,
the astronauts were in real danger of getting lost.
And, let’s be real: Everything on the Moon
just kind of looks the same.
To overcome that, a first-of-its-kind computer
combined data about the rover’s orientation,
taken from an onboard gyroscope,
with odometer readings from each wheel.
That let it track the vehicle’s exact
meter-by-meter progress across the surface
and plot a direct course back to home base.
And just in case that failed, each
astronaut also had to learn to read
a special lunar sundial to determine their direction.
Single-use batteries powered everything,
but power was never actually a problem.
Instead, the limiting factor was the rule
that barred astronauts from driving
farther away from the lander than they had
air left to walk back, a few kilometers or so.
That way, if the buggy broke down,
they still had a way home!
All-told, the lunar roving vehicle
seemed like a miracle machine,
and all that wizardry doesn’t come cheap.
On average, each rover would
cost about $60 million today.
Fortunately, we put them to good use.
Apollos 15, 16, and 17 each brought a rover,
and all were driven more than 25
kilometers over at least three hours.
With them, astronauts were able to bring back
individual rocks with masses as much as
11.7 kilograms, more than half
the total picked up on Apollo 11.
Also, since the lunar landers had to touch
down a safe distance from things like big craters,
the Moon buggy opened up those areas
for closer study on all three missions.
On Apollo 16, it enabled John Young and Charlie
Duke to drive more than 150 meters higher
than their landing site in search of samples
of the area’s unique geology.
And the crew of Apollo 17 used their rover
to deploy literal bombs on the surface.
Just in case you needed another reason
to think Apollo astronauts were cool.
When exploded, these bombs created
tremors picked up by seismic sensors
and used those to understand
the physics of the Moon’s crust.
The experiment revealed that the top layer
of the Moon’s crust is about 1.4 kilometers thick.
It’s also a lot more broken up
than similar areas on Earth,
probably because of the
constant impacts from space.
All together, the Moon buggies
were quintessential Apollo.
They were ultimately designed in only
months and did so much with so little,
relying on clever engineering and
state-of-the-art computers to enable exploration.
Without them, we’d probably know a lot
less about the Moon than we do today.
Which might make them a little
cooler than, say, a Tesla.
And, hey, what’s more American
than a car on the Moon?
So, NASA scientists had to do A LOT of
creative thinking and problem solving
to figure out how best to design
and use the Moon buggies.
And that made me want to work out
my own spatial problem solving skills.
That’s one small step for man,
and now I’m really tired.
Anybody got a moon buggy anywhere?
Brilliant.org has a ton of great spatial reasoning
quizzes, and today I’ll be taking the
3D Geometry Puzzles Shortest Distance quiz.
[tires squealing]
It starts out a little like the story
of the
tortoise and the hare,
but it’s an ant and a fly trying to
make their way through a 3D cube.
They even put them there so you can visualize
it, and I think they’re pretty stinkin’ cute!
In this case, the ant definitely has
the longer distance to travel,
because it can’t fly through the cube
and has to walk along its edges.
As you get deeper into the quiz,
it gets more complicated and
I almost wanted to make a 3D model
to help me think through the distance.
[honking]
What’s cool, is that I’m not alone in this.
When you view the solutions,
Brilliant has created 3D to 2D models
to illustrate how to think through these problems.
So give them a try.
And right now, Brilliant.org is offering the
first 77 SciShow Space viewers
that sign up at brilliant.org/scishowspace 
20% off their annual premium subscription,
and you’ll support SciShow Space, so thanks!
[♪ OUTRO]
