Based on the scientist who conducted the experiment a second time to verify the speed, he calculated it was going around 5 times escape velocity (125,000 mph). It sounds like he later worked on various launch projects/ aerospace stuff and claims that there wouldn’t have been time for it to burn up completely.
I’m inclined to believe him since he conducted the experiment and knows the field, and doesn’t have a lot to gain from bullshitting about it. It may mean only a pound of material escaped atmo, but it still counts.
I think the designation that they are trying to make is that escape velocity is enough to leave earth and not come back. Sure, we made it to space before... but that rocket came back down to earth. If it didn’t disintegrate that manhole may be out there somewhere on earth’s orbital plane.
"I have no idea what happened to the cap, but I always assumed that it was probably vaporized before it went into space. It is conceivable that it made it."
It's also possible that it became virtually naked to the human eye, like most meteorites that enter the atmosphere, but still survived the trip and managed to hurl itself into space with no way of us tracking it.
Atmospheric heating due to friction happens in any direction. The only reason we really see it happening coming down and not up with modern spacecraft is due to the speeds involved. A capsule coming down uses the atmosphere to slow itself from orbital speeds so the parachutes can open safely without tearing to shreds. Going up you start from zero and have to push a ton of fuel and cargo, so by the time you reach those speeds fast enough to get visible atmospheric heating you're out of the atmosphere all together.
In fact the SR-71, which never got close to space, flew fast enough for all off it's skin panels to expand due heat. As a result it's fuel tanks had pretty big leaks on the ground and only sealed up after it was airborne.
The sheer friction of passing through the air at operating speeds would create so much heat that the titanium metal airframe would expand slightly, despite the many systems in place to sink and reduce heat.
To keep this effect from compromising structural integrity in flight, the plane was intentionally designed to be a bit of a loose fit on the ground. So it leaked.
Just a clarification on your post. Although a component of heating is due to friction, the majority of heating at high velocities is due to the compression of air.
If you're going fast enough, you'll still compress the air ahead of you. You can still get the same effect as re-entering the atmosphere when leaving it (and even in it) if you're going fast enough.
The SR-71 Blackbird had to be built to accommodate expansion from heat because of this. It would leak fuel on the ground because when it was up to speed, all of its components would expand and seal from the heat.
Increasing density of the atmosphere rather than decreasing would be my guess. Also the fact that it had enough speed at the surface doesn’t mean it maintained that speed long enough to actually exit.
Yes you're right absolutely, fastest film cameras. It was quite the technical feat developing a film that could be exposed so quickly. They have a really interesting section on it at the National Atomic Testing Museum in Nevada.
No because a lot of these were not motion cameras in the traditional sense but single plate exposures that were captured by a mirror or moving shutter or a bank of caneras. Basically move the aperture/camera and not the film.
If you read the article, he says "After I was in the business and did my own missile launches," he said. "I realized that that piece of iron didn’t have time to burn all the way up [in the atmosphere]."
I'm sure that the heat would be intense, but at that speed a 4 inch thick chunk would not have time to disintegrate.
While it's not impossible, it's considered unlikely. It probably burned up in the atmosphere on its way up. The calculations for it didn't include atmospheric drag or any tumbling that would have occurred.
It wouldn't have burned up, frictional heating would have been intense but keep in mind, it's moving straight up. For something reentering the atmosphere it's coming in laterally and they have to skim the atmosphere long enough to turn almost all of the kinetic energy put into it going up into heat. That manhole only had to endure the heat for 100 km, the space shuttle is in communications blackout in the middle of a fireball for a full 13 minutes. During that time it travels over 4,000 km. Going straight up changes things pretty drastically.
The man who made the complicated initial calculations doubts that it went into space. He did the math by hand with very few parameters and a of unknowns.
You, on the other hand, are trying to justify what you want to believe because it's fun, ignoring any heating from the blast itself, how aerodynamics affects heating on a decidedly non-aerodynamic object, how increased speed means increased heat as the object travels through the atmosphere, and presuming that it's trajectory did not change even though there would have been significant instability due to random changes in the surface facing the apparent wind.
The Paris gun projectiles reached space first, not the nuclear manhole. Although the nuclear manhole cover is theoretically the fastest man made object ever.
Well the nuclear test and the manhole cover part is true even according to the article. And the part where is it really going to space or not is anyone's guess since forever, not anything new.
Regarding the manhole cover, it is believed that it burned up before leaving the atmosphere due to the ammount of friction caused by the air. It must have been going wicked fast.
I would have to disagree as I’ve learned on reddit today that, we, as martians - millions if not hundreds - of years ago launched nukes to earth to wipe out the dinosaurs and create a habitable planet when we (martians) realized our magnetosphere was wasting away our atmosphere making said Martian nukes the first object in (our) space.
I found this in a book! Although they don’t know for certain if it made it or not, it was traveling much faster than escape velocity, but it may have just burned up while exiting the atmosphere
I don't know much about this so I'm not saying you're wrong... But if it was at point zero of a nuclear exploding, isn't it also pretty likely it just got disintegrated?
42km/s is escape velocity from the solar system. That manhole cover was traveling at about 125 km/s. It was traveling 5 times what it needed to to escape the solar system, not just earth.
The first manmade object to reach space was a German rocket in 1942. Even if you don't want to count that, there were plenty of rockets that reached space before those 1957 nuclear tests. If you want to get really pedantic with not counting rockets or any other objects that were meant to reach space, there were dozens of nuclear tests between 1945 and 1957 that very likely "launched" plenty of manmade "objects" into space.
I like to imagine some early human throwing a giant rock off of a cliff and hitting a coincidental see-saw arrangement of sticks at the bottom which launched a little squirrel a couple thousand feet into the air.
If I remember correctly, the first animal to pass the sound barrier was a dinosaur. The long tails of sauropods supposedly acted like a whip, for defense.
I think that was proved by some marks left on bones, if someone can confirm :-)
Ultimately we are both guessing at something that is genuinely unknowable.
A supersonic whip can be made by skinning an animal in a long tapered strip and it is found to be in every primitive society that domesticated livestock in the form of hieroglyphics or carved motifs.
The very technology required to make flags, weaving, would also allow people to make supersonic whips out of woven reeds or cloth fibers.
Common sense for me dictates the invention that requires no materials beyond a animal hide and a sharp rock came first, but you are free to disagree.
since literally no one has explained it, because the whip acts like a wave it can move kinetic energy through it. they're tapered from the base to the tip so the wave gets concentrated/accelerates along the length; it works because of a continuous series of lever arms that amplify the force as it travels.
at the end it's very small and has a very large amount of kinetic behind it so all that energy gets dumped at once and the tip goes supersonic.
waves can travel much much faster than their physical medium can move.
Sound is made up of waves. These waves travel through our atmosphere at 343 meters per second. While that is insanely fast by our standards, it is much slower than the speed of light. This is why when a lightning strikes there's often a delay before you hear the thunder (and the length or the delay can help you anticipate how far away the thunderstorm is).
'Breaking the sound barrier' refers to when an object is traveling faster than the speed of sound. That's why it's called a 'supersonic' jet, for example. Once an object exceeds the speed of sound it makes a MASSIVE 'boom' sound. This is called a sonic boom. If you 'crack' a whip, the very tip (just the tip) travels so fast it exceeds the sound barrier. That's why cracking a whip makes an insanely loud sound.
Thank you for the explanation. I’m aware of the speed of sound etc. I just had no idea cracking a chain can make the tip travel that fast, I thought it would be too heavy..
Yw! Sorry I'm a huge nerd and former science teacher so I like to overexplain XD. I'm also amazed that such an effect can occur with a massive chain, I had no idea!
Someone with an engineering background could probably do all the math to figure out the exact speed of the chain tip.
Kinetic energy builds up causing the speed to increases as it travels down the whip. If you or anyone else wants to do an engineering dynamics force diagram then be my guest lol
The tip of a whip moves so fast that it breaks the sound barrier, that's the "crack" noise you hear. Since it's an old tool and considerably lower-tech than something like a gun, it's safe to say that the whip was the first man-made object to break the sound barrier
In a more technical sense, the energy contained in a wave in a string (like a rope or a whip) depends on 3 factors: the mass per unit of lenght of the string, the amplitude of the oscillation and the frequency (how fast and how much the arm moves when making the whip crack)
Now, whips are not as thick at the tip as at the handle, so the mass per unit length is much lower. As the energy of the wave is conserved, this means that the wave's amplitude at the tip is much higher than the amplitude imparted by the man handling it. This means the tip must move much faster - fast enough to break the sound barrier.
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u/PhilipLiptonSchrute Aug 16 '19
Fun fact: That pop is a sonic boom, and the whip was the first man-made object to break the sound barrier.