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Hello and welcome back to highly ambiguous inquiries.
So what’s the fastest manmade object ever?
I’ll give you a hint—it’s not the US military when a developing country finds oil,
it’s not James Charles’ plummeting subscriber count, and it’s not Sonic—the terrifying
human-toothed shrew-Gollum that haunts my nightmares.
What is the answer?
Well, if you’ve watched this channel before, you probably know what I’m going to say—it’s
complicated… and good for watch time.
If we’re talking about moving on land, then it’s the ThrustSSC, a British rocket-car
that looks like it should be piloted by either James Bond or Anakin Skywalker.
Its actual driver, British fighter pilot Andy Green, for apparently no reason other than,
“hey, why not,” drove it to top speed in the middle of the Black Rock Desert, reaching
the record speed of 763 miles or 1,228 kilometers per hour on October 15, 1997.
But we’re really not talking about the fastest manmade object on land because this video’s
not long enough yet.
If we’re talking about travel through air, though, then that’s another story—a much
longer, and much stranger story.
Starting in 1945, the United States began conducting tests of nuclear bombs.
At first, most of them were above ground, but in the late 50s, people started to think,
“blowing up air isn’t satisfying enough,” and, “maybe this radiation thing isn’t
too good for us,” and so they moved the big boom tests underground.
The thing is though, they didn’t really know what would happen.
The first test was conducted on August 27, 1957.
They dug a long, cylindrical hole into the ground, put the bomb in it, put a two ton
concrete plug at the top of it, which was covered by a 4 inch thick, steel manhole cover.
Then, as one does, they went ahead and set off the bomb.
To their surprise, the concrete plug was vaporized instantly, turning it into a mass of superheated
gas that expanded and essentially made the entire hole into a gigantic gun barrel.
When the gas hit the manhole cover, bam.
It was blown off the ground instantly, shot into the sky, and disappeared out of sight.
Now, normally we’d just shrug our shoulders satisfied with the continued mystery of how
fast the manhole cover went and get back to inconsequential nuking of the ground, but
luckily, this time there was a high-speed camera on site that caught a glimpse of the
manhole cover.
The camera shot at 1 frame per millisecond, or 1000 frames per second, and it only caught
the manhole cover in a single frame which allowed them to calculate, using math stuff,
a lower bound for the manhole cover’s speed.
By looking at where the manhole cover was in the frame, and then calculating the distance
between there and the bottom of the frame, we find the shortest possible distance it
could have traveled between when the last frame was taken and when this frame was taken.
In other words, we’re assuming that when the frame was taken, the manhole cover was
here, just below the frame.
Then we take that distance, and divide it by 1 millisecond—the time between the frames—to
get distance per second.
So, we’re basically saying, if the manhole cover was here, and then one millisecond later
it was here, how fast did it travel?
Now, we can’t do the actual calculation ourselves, because the government has never
released the video and for some reason refuses to declassify it for what is one of the internet’s
most regarded YouTube channels, but we do know that the scientist conducting the experiment,
Dr. Brownlee, took that information from the high-speed camera, combined it with calculations
of the blast force from the bomb, did math things, and reported that the manhole cover
had been moving at six times the earth’s escape velocity which would put it at around
125,000 miles or 200,000 kilometers per hour or 34 miles or 55 kilometers per second.
So like, fast.
There is disagreement as to whether or not the manhole cover made it into space.
Some say that it would have burned up on its way out of the atmosphere, while others say
that it may have been moving so fast that it wouldn’t have had time to burn up.
Either way, just like my ability to write decent jokes, the manhole cover has never
been found.
If it did really make it into space, it would have been the first object ever launched into
space.
The experiment happened on August 27, 1957—just over a month before Sputnik’s launch on
October 4, 1957.
Take that, commies.
As of today, it seems that no other object has managed to come even close to the manhole
cover’s speed while still in the Earth’s atmosphere.
If we count space travel, though, then the manhole cover has met its match.
Although the manhole cover would have been moving over 4x faster than Apollo 10, the
fastest manned space vehicle, its record for fastest manmade object was surpassed in the
1970s by NASA’s Helios probes, and then again in 2016 by the Juno probe.
The Helios II probe became the fastest ever manmade object in space in 1976.
The probe, designed to study the sun, was in an elliptical orbit around the sun.
Because it followed the conservation of angular momentum, its speed increased as it got closer
to the sun, and it eventually topped out at 157,000 mph.
Then, just recently, in 2016, the Juno space probe broke that record, when it was sucked
in by Jupiter’s gravitational pull, reaching 165,000 miles per hour.
It was actually moving so fast that it had to hit the brakes so that it could enter Jupiter’s
orbit instead of flying right past it, but it’s also important to note that both of
those probes only reached those speeds by using the gravity of the Sun or another planet
which kind of feels like cheating.
I mean, if I was allowed to use the Sun’s gravity to pull me, I maybe wouldn’t have
come in last place at my 7th grade track meet.
So, if we only count self-propelled objects, then, unbelievably, the manhole cover still
reigns supreme.
What should really be the fastest object in human history, though, is your mouse when
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