Julius Caesar died in 44 BC, 2,025 years
1 month and 3 days before the first shuttle took off from Launch Pad 39A in Cape Canaveral.
But despite more than 2 millenia separating these events, the Romans actually played a
huge role in designing the space shuttle and it all had to do with a horse's ass.
Different countries have different trains.
China has the CR400AF, Germany has the FS Frecciarossa 1000,
and America has the Acela. By far the worst of the three. It’s basically Kevin Jonas of trains.
But you might be asking yourself.
Gee, I’ve never seen a train before? What are they? Are they basically cars?
Well dear viewer, you’re right a train is basically a car, just on tracks,
and those tracks are what we’ll be focusing on.
Tracks across the world come in different gauges, that’s the distance between the inner phases
of the tracks. Narrower gauges are cheaper but wider gauges allow for bigger and faster trains.
Most developed countries use the standard gauge of 4 feet 8 and half inches (or 1.4 meters), but
former soviet union countries use a slightly wider gauge at 4 ft 11+27⁄32 of an inch (or 1.5 meters).
Most of the world uses one of these two gauges, but there are some exceptions.
Most of south africa uses the much smaller three foot six inch [1.06 meters]
and even Spain uses its own rail gauge of 5 ft 5+21⁄32 of an inch [1.668 meterse] widely
believed to be used to prevent a possible French invasion from using the rail system.
But like we always do in this channel, let's focus on the Americans. Their tracks are 4 feet 8 and
half inches and we’re gonna see this is a somewhat special number. Why’d they use this gauge?
Well, in the 1800’s while Americans were busy invading mexico and manifest
destinying across the continent they were also building railroads. In just six years,
20,000 men built a railroad 1,900 mi (or 3,000 km) miles from Omaha Nebraska to Sacramento
California. Shrinking cross country travel from 10 months by waggon to just one week by rail.
But when Americans rushed to build the railways the people with all the
experience were the British. So they used their expertise and equipment
and American rails ended up being the same gauge as the British ones.
But why were British tracks 4 feet 8 and half inches to start. Well that’s because
the first English railways were built by the same men who built pre-railroad tramways. Again,
the people who built the English rails used the same equipment as the people who built
the earlier trams, meaning they had the same length; 4 feet 8 and half inches.
Those trams were built so they’d fit in the ruts of the very old, long distance roads
that connected smaller English cities. The wheel ruts in those roads? Yep, 4 feet 8.5 inches wide.
And I think you know where we’re going with this.
2 thousand years earlier, those first roads were built by and for the Roman Empire.
Now the Romans didn’t build roads with grooves in them.
They traveled by horse drawn chariot. All the chariots were made to the same specification,
and the weight under their wheels are what carved those divots in the roads.
And the final piece of the puzzle; Why were the chariot wheels spaced at 4 feet 8.5 inch?
The chariots were designed to be drawn by two horses. The width of the chariots’
wheels needed to accommodate the widest part of the horses — their rear ends. Back then,
a horse's rear was about two feet, so add a little margin for the Nikki Minaj
horses out there and that gave us 4 feet 8 and a half inches.
But how does this get us to the space shuttle? Those fly in the air, not on ancient roman roads.
The space shuttle was made of 2 and a half million parts made by hundreds of companies across the
country. And one of the most critical parts were the solid state rocket boosters. These two things
sticking off the sides, 13 stories tall. And these gigantic boosters were built in Utah.
But if the rockets got launched in Florida, why build them more than 2,000 miles away.
Well, originally NASA looked at making the boosters in Florida with the Aerojet 260 booster.
They wanted to cast the aluminum exterior in Florida because the 22 foot diameter
and massive weight meant it couldn't be transported very far.
But when they tested the rocket there were instant problems. The outer casing couldn’t
handle the stress of the test fire and the motor itself basically disintegrated. These problems
were traced back to the variable temperature and humidity during the casting. Basically Florida’s
weather was so inconsistent that the different parts of the boosters that were cast at slightly
different times had different structures, and where they met stress fractures could easily form.
But luckily the air force had contractors that had decades of experience building rockets for them.
And the only difference between the Air Force’s rockets and NASA’s
would be whether there was a big boom at the end.
Like everything in life, there was good news and bad news. The good news is the contractor,
Morton Thikol, was based in Utah, and Utah has a very cool dry climate, with low humidity.
This helped them be very consistent when casting,
especially when casting multiple different segments for the rocket.
But the bad news? Well, the rockets were ridiculously heavy.
They would be too big for road transport, and, at 1.3 million pounds or 600k kg,
were more than triple the maximum lift capacity of the largest aircraft in the world.
This isn’t a new problem for NASA. In the 60’s NASA had to transport the second stage
of the SAturn rocket, at more than 1 million pounds (or 480,000 kg) from the production
plant in California to the testing facility in Mississippi. And they did this with the
use of Orion and Poseidon, NASA’s two barges, going through the Panama canal.
But in case you’ve never seen a map, or confuse Utah with the 20 other square shapes that look
just like it, Utah doesn’t touch the ocean, and doesn't have any water shipping ports capable of
shipping them by barge. This all meant the only realistic way to transport boosters was by rail.
So, the boosters were manufactured in Utah and had to be shipped to NASA’s Kennedy Space Center
in Florida by rail. But along the way the boosters had to pass through the Moffat tunnel in Colorado,
a 6.2 mile long track, barely wider than our 4 feet 8 and half inches tracks. The rocket sections
had to fit through the tunnel and so the engineers were forced to completely redesign the boosters.
The final boosters designed for the space shuttle just barely fit through the tunnel
and were only half as wide as the boosters originally designed
in Florida (but they made up for less total thrust by being twice as long).
And so a decision by a roman emperor 2000 years in the past, ended up redesigning one of the
most advanced vehicles we’ve ever made. Sometimes your decisions can have surprisingly wide reaching
consequences. But NASA does a lot more than just design rockets, checkout this video to
see 13 inventions nasa research gave the world. And don’t forget to like and comment since the
algorithm likes to see that on us small channels. And remember, there is always more to learn.