
The links to the details are worth following, any scientific test where the report includes the phrase "the hypersonic expanding column of vaporized concrete" must have been spectacular, whatever happened!
As any space enthusiast knows, beachball-sized Sputnik was the first manmade object to orbit the Earth after it was launched by the Soviets in October 1957. But it's possible the US managed to put an object into space a few months before that. In 1956, astrophysicist Dr Robert Brownlee was asked by his boss at the Los Alamos …
Escape velocity is the thing, presumably the assumption is that the thing could have been still shifting at a good lick when it left the atmosphere and entered an orbit with a parabolic trajectory if any part of it has survived the heating on the way up (which would have been combined with the momentary effect of the blast). It would have been possible to calculate is the mass of that plug could hold that much energy without disintegrating.
First to Sub-orbital space was probably Werner with his V2.
But whatever, if there was nuclear blast energy being hosed vertically out of the end of a tube then we need video. This just has to be seen. Anyone know of any links I would be very interested.
Paris Gun would only achieve 25 miles in altitude on a normal range shot.
A V2 however would reach 55 miles (88km), on a range shot, but could achieve 128 Miles (206km) if fired vertically upwards.
Neither of these would achieve any kind of orbit. The V2 however would cross the 100km Karman line.
*IF* the manhole cover escaped Earth it would likely still be on a Solar Orbit..
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I'm afraid you misunderstood the impact depth equation. It all depends upon momentum transfer. The momentum is transferred to whatever it is hitting (in this case the atmosphere, which is equivalent to about 10 metres of water). If it could push it aside then it wouldn't be applicable. Wikipedia actually does a resonable take:
https://en.wikipedia.org/wiki/Impact_depth
How far can you throw a 2p coin?
For its thickness Impact depth states 2mm (6660/1.22) = 11m
However this disc will tumble and shed air. its going to go much further than impact depth on its thickness predicts, so perhaps the calc should be done on its diameter...
Nope. The solar escape velocity of the Sun at the distance of the Earth's orbit, is a shade over 42km/s.
So IF that things survived passage through the Earth's atmosphere (and it seems to me that the probability of that happening at that velocity is rather small), it was headed for interstellar space, and would have got there well before Voyager.
"So IF that things survived passage through the Earth's atmosphere (and it seems to me that the probability of that happening at that velocity is rather small), it was headed for interstellar space, and would have got there well before Voyager."
Surely that depends on what direction it was going in comparison to our orbit. If it were facing the opposite way to our orbital trajectory (launched at 6am or 6pm, not sure which), it would have lost orbital 'speed' and effectively moved to a lower solar orbit.
If the object exceeded escape velocity, it would not enter any shape of orbit around Earth, it would just carry on until it hit something or got captured into orbiting another body (thinking about it, it probably would orbit the sun).
Not exactly, if I understand Wikipedia right (and it's explanation is not the clearest). The object would escape earth if launched directly upwards. After escaping earth, it would have to contend with the Sun's much greater gravity, and might start to orbit the Sun. If launched at an angle, the object would achieve "escape orbit" from earth, a parabolic path but not a closed shape, which I don't quite understand the sequence of events.
Most probably, the first man-made object outside atmosphere was V2, the first man-made object on Earth orbit was Sputnik. This plug, if it did not disintegrate (and most likely it did) and kept escape velocity when it exited the atmosphere, could claim to be the first man-made object to go to space and stay there.
Otherwise, that would be Luna 1, launched in 1959.
My father tracked the first orbit of Sputnik in Dublin using a rig he designed and built himself! Our family grew up with the sounds of various Russian and US satellites ringing around the house.. No wonder my sister built a SaturnV instead of a doll's house :) And I ended up here!!
Considering the technology in use in that era, it's surprising it wasn't ticking and required a manned mission to wind it back up.
Considering that state of the art of that era was vacuum tubes, which intensely disliked high G acceleration.
So, a tip of the hat to the ingenious Russians of that era!
Nationalism and space is a bad idea.
Considering that state of the art of that era was vacuum tubes, which intensely disliked high G acceleration
You are thinking of the variety used in living room equipment, with thin glass and delicate insides. Ruggedized equipment used much more sturdily built ones. I have a very small tube from a WW2 German military radio (probably) somewhere among my assorted junk. It does not even have a socket, just wires coming through the thick glass and says "Wehrmacht" on the label.
Hmm, interesting. If I calculate correctly, a 55ton yield gives about 55*4GJ energy (since 1Mton is 4PJ), so that if all the explosive energy turned into the kinetic energy of a 100kg lid, it would end up travelling at 0.0002 of c as well.
Perhaps that was the original calculation :-)
(bah - half ton lid ... so erm, 0.0001 of c)
Unfortunately, the bomb yield was much greater than anticipated – 50,000 times greater, apparently.
The disappointment being that this test was intended to be an accidental detonation safety test, with a yield of 1-2 pounds! The 50,000-times-greater yield only amounted to a yield of 55 tons. It doubtless still made an impressive Roman Candle, but not the multi-megaton bug-planet-threatening manhole-cover cannon I'd been envisaging from the article!
Probably not as bad as the Castle Bravo nuclear test shot, which was only supposed to be 5 megaTons, but, instead, was closer to 15 megaTons. It seems that the designers missed the fact that the Lithium in the Lithium-Deuteride boost fuel would contribute to the fusion. Whoopsie.
https://en.wikipedia.org/wiki/Castle_Bravo#Detonation
And, yeah, that would require a change of underwear!
Note that some of the islands in the Bikini Atoll no longer exist. Bokonijien, Aerokojlol, and Nam were vapourized during nuclear testing.
https://en.wikipedia.org/wiki/Bikini_Atoll#Geography
Dave
P.S. Despite the island chain giving name to a popular type of swimwear, the natives are very modest.
https://en.wikipedia.org/wiki/Bikini_Atoll#Clothing_and_dress
https://en.wikipedia.org/wiki/Bikini_Atoll#Swimsuit_design
Pikinni ("surface of coconuts") -> Bikini. Quite descriptive!
https://en.wikipedia.org/wiki/Bikini_Atoll#Etymology
"The island's English name is derived from the German colonial name Bikini given to the atoll when it was part of German New Guinea. The German name is transliterated from the Marshallese name for the island, Pikinni, ([pʲi͡ɯɡɯ͡inʲːii̯]), Pik" meaning "surface" and "Ni" meaning "coconut", or surface of coconuts.[2]"
Superpowers spend a lot of time scrabbling for evidence that they did just about everything before anyone else, even if by accident and with no useful result. I may as well claim that my first fart in 1955 included six hydrogen molecules which made it to the interstellar void. Russia was in space first, nearly 60 years ago: apparently that still smarts.
Not so much. I remember first hearing this story at least 20 years ago, and I got the impression it had been in circulation for quite a long time even then. I don't think there's any current smarting taking place, although that might have been the case during the Cold War, when it seems this story first appeared.
>Russia was in space first, nearly 60 years ago: apparently that still smarts.
In the end it was all a matter of who kidnapped the best Germans anyway. The only reason the US lost was not trusting Von Braun sooner. I still honestly believe if he dies in WW2 even today we never would have went to the moon. We recently saw how good the Russians version of the Rocketdyne J-2 engines was when the rocket it was on recently blew up.
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See https://en.wikipedia.org/wiki/Impact_depth
The Earth's atmosphere is roughly equivalent, in kilograms per square metre, to about ten metres of water. You can't shoot a manhole cover through ten metres of water, either, I would guess, though I've not tried it.
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I ran the numbers on this event a while back during a discussion about it in an email bounce...
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Working the numbers as I go along while poking Dickipedia with a long stick... specific heat of steel averages 620J/kg per deg C. The steel lid is about 600 cubic inches if the size you give is correct, that's about 10,000 ccs in volume. Typical steel density is 7.9 g/cc so the lid weighed 790kg. Melting point of steel is about 1500 deg C so it would take 620 x 1500 x 790 Joules or about 750 MJ for complete slagging of the plate. I am ignoring any radiation heating from the explosion (X-rays, neutrons, gamma flux etc.) as I assume the cap was a last-defence thing and not directly coupled to the Device which was Exploding (i.e. it was not line-of-sight to the device).
Assuming the 50km/sec figure at ground level is correct and that is a SWAG at best -- explosive-gas-driven devices such as artillery shells top out at about 2 km/sec and light-gas guns using hydrogen or similar low-mass gasses are not that much faster -- then its kinetic energy on "takeoff" was 1/2 M x V^2 = 1/2 x 790 x 50 x 50 x 10^6 = 1TJ or over a thousand times as much energy as required to melt it completely. The Pascal-B shot only yielded about 300 tonnes equivalent, or about 1.25TJ which would mean the explosion would have to have expended 80% of its energy in driving the plate to that speed.
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There are other factors which also indicate the manhole cover never reached anything like escape velocity -- the shaft to the Pascal-B device was 150 metres deep and about 1 metre square assuming the size of the cap so there's another 180kg of air to be accelerated up to at least 50km/s before it hits the underside of the cover. There's also friction with the walls of the shaft, energy losses in compressing and heating that much gas etc.
Pity.
If the Pascal B steel plate was traveling at 66 km/s, it would have experienced a drag force due to the atmosphere equal to roughly 0.5 x rho x V squared.
https://en.wikipedia.org/wiki/Stagnation_pressure
This is .5 x 1.3 kg/m3 x 66000^2 m/s = 2.8E9 Pa = 475,000 PSI.
This is well above the yield strength of steel at the high temperature created on the plates surface. That temperature is far more complex to calculate because it involves an equilibrium between energy gains and losses and the heat capacities of the materials as they change from solid to liquid to gas to plasma. This is the situation involved in nuclear re-entry and space capsule re-entry and meteor entries into the atmosphere.
A semi-sophisticated ablating vehicle trajectory model was used to model launch of a carbon-carbon plate at 66 km/s at sea level.
This model indicates that the carbon carbon plate ablates about 1 cm every 20 microseconds under these conditions. This is a best case projection that assumes the plate stays intact - which it would not because the stagnation pressure would greatly exceed the yield strength of the carbon carbon.
After 400 microseconds (0.0004 seconds), the ablation depth would be 20 cm ( 8 inches) and the altitude would be about 200 meters. Carbon carbon survives these conditions much better than steel. So the steel plate would evaporate and turn to plasma very soon after launch.
Unlike a steel plate, a nuclear re-entry vehicle like shape with a carbon carbon nose will make it into space if launched below the velocity at which the nose will fail due to atmospheric stagnation pressure. A semi-sophisticated ablating vehicle model shows that a carbon carbon cone designed to be aerodyamically stable even with nose ablation, weighing 1000 kg, with a 76 cm base diameter and a 380 cm length, launched at 13 km/s at sea level will leave the atmosphere somewhat above escape velocity of 11.5 km/s. The nose ablation will be roughly 25 cm.