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Boy, the way, at the end of the video, I'm like, "actually speed doesn't exist" is wild. The fastest thing in the universe might actually be you...just depends on your frame of reference...


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Good morning, John, it's Monday!
And Pizzamas is going by very quickly-- so quickly that it is reminding me of a video that I've wanted to do for a very long time. Because I'm fascinated by what happens when you ask seemingly simple questions. Like, for example, what's the fastest thing? 

Sounds like that would be really objective and that you could just answer it and be done with it, like the answer is light. Light is the fastest thing. But is light a thing? It's not matter, it doesn't have mass, I can't, like, grab it. 

Also, in some cases, particles can go faster than light, as long as the light isn't travelling through a vacuum. So...meh.

The interesting thing to me is that I think a bunch of different people could have this same title for a video and make very different videos. But here's the video that I would make: Here are the top four, six, I don't know, things that are the fastest.

Let's start out with the fastest a person has ever gone. Now for a long time that was just running, and then horses, and actually I have bad news. It was neither of those things. For a long time, the fastest person was someone who did not survive, because they were falling off of something that was very high up. The terminal velocity of a human body in our atmosphere is 120 miles per hour. You can easily reach that if you fall off, just, you know, a number of different waterfalls. And the 120 miles per hour that somebody probably experienced while falling off of a waterfall or a cliff somewhere, was not exceeded until the 1900s! Specifically, probably, in the 1910s or 1920s. We're not entirely sure, because cars were very new and people were driving them very fast and we didn't have great ways to measure how fast they were going. Anyway, people were definitely going over 120 miles per hour by the 1920s.

And then over the next few decades, we rapidly increased our top speed until the 60s, when we had gone from 120 miles per hour to over 24,000. And that record, set in the 1960s by three people at the same time, has not yet been beaten. And we are not on the way to beating it.

The three people in question were Tom Stafford, John Young, and Eugene Cernan, and they were on the way home from the moon, which they did not land on because this was Apollo 10. It went faster on the way back to earth than any other Apollo mission. I don't think because, like, they were in a hurry to get home. I'm guessing it was just because of, like, orbital mechanics reasons. But yeah, that's the fastest a person has ever gone and we're not looking to exceed it until, probably, we head to Mars. 

But we have made lots of things that have gone way faster than Apollo 10. But here's the thing that's pretty easy to understand: as an orbit gets lower, it gets faster. So Mercury orbits the sun faster than Venus, which orbits faster than Earth, which orbits faster than Mars. And so if you want to get a probe really close to the sun, to do science on the sun, it's going to be going very fast during the part of its orbit when it's close to the sun.

And that brings us to the Parker Solar Probe, which this year broke its own record for the fastest a man-made object has ever gone, with around 330,000 miles per hour. Now, very strangely, this might not be the fastest a man-made object has ever gone. 

If you remember my 2017 WheezyWaiter paternity leave video, you'll know about this, but it might be that the fastest man-made object ever was the manhole cover that capped an underground nuclear test that went slightly awry.

The shock of the explosion was vented improperly, and so it all went to this one manhole cover, which was then of course blasted off. There was high-speed camera running and the manhole cover appears in one frame of the high-speed film. That allowed scientists to calculate that, at minimum, it was going at 125,000 miles per hour. And there wasn't enough data to put a maximum on that, so it could've been going significantly faster than that. That manhole cover may have been blasted into space, where it would still be, or it may have vaporized as it slammed through the atmosphere. Either way, it did not fall back to earth.

And that brings us to the final question. Alright, so those are the fastest things that we've made; what's just the fastest thing, Hank? What's the fastest thing? And if we're not counting light in a vacuum, because of course that is the fastest thing, the fastest stuff that has mass? Well that would be, like, the super heated jets of plasma that come off of active galactic nucleuses. So, super massive black holes in the center of galaxies, called blazars. Balzars shoot big globs of this plasma out; some of them, like, as big as the planet Jupiter, going over 99% the speed of light. Why does this happen? I have no idea. 

And then, here at the end, a quick note: Speed is a function of distance and time. And time, it turns out, is relative, and so speed itself is kind of doesn't exhist. 

But Pizzamas does! And it's going fast. And you can go to right now to see all of the amazing products that we have available now, that will never be available after the end of this week.

John, I'll see you tomorrow.

The fastest thing in the world: It's me!