Possible Challenger To Sputnik, manhole first manmade object in space? |
Possible Challenger To Sputnik, manhole first manmade object in space? |
Jan 3 2006, 06:40 PM
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#16
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Senior Member Group: Members Posts: 2488 Joined: 17-April 05 From: Glasgow, Scotland, UK Member No.: 239 |
QUOTE (tty @ Jan 3 2006, 06:50 PM) Actually, if You throw a rock into the air by hand it also goes into an elliptic orbit around the Earth with the perigee (way) under ground level. tty Yes, very true - and a great classroom demonstration - it's easy to see, cheap to perform, and you have a fairly profound aspect of the universe right in front of you! Bob Shaw -------------------- Remember: Time Flies like the wind - but Fruit Flies like bananas!
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Guest_BruceMoomaw_* |
Jan 3 2006, 07:36 PM
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#17
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Guests |
I first read about the manhole cover years ago in a letter to "Smithsonian Air & Space Magazine". Since it weighed several hundred km, there's an excellent chance that some of it survived its trip through the atmosphere -- and while it certainly was not "the first object to enter space" (the best claim for that honor probably goes to the Aerobee second stage on that 1949 Bumber-WAC launch from White Sands), it would have been both the first man-made object to escape from Earth and the first one to hit solar escape velocity.
Moreover, in (I believe) Nov. 1957, a small suborbital research rocket was launched to detonate, at high altitude, a grenade stuffed with little metal pellets to simulate micrometeoroids entering the atmosphere; and photos indicated that at least two of them went upwards at more than escape velocity, and that some portion of them likely survived the air friction. |
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Jan 3 2006, 10:27 PM
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#18
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Member Group: Members Posts: 688 Joined: 20-April 05 From: Sweden Member No.: 273 |
QUOTE (BruceMoomaw @ Jan 3 2006, 09:36 PM) I first read about the manhole cover years ago in a letter to "Smithsonian Air & Space Magazine". Since it weighed several hundred km, there's an excellent chance that some of it survived its trip through the atmosphere -- and while it certainly was not "the first object to enter space" (the best claim for that honor probably goes to the Aerobee second stage on that 1949 Bumer-WAC launch from White Sands), it would have been both the first man-made object to escape from Earth and the first one to hit solar escape velocity. The second stage of the Bumper WAC was a WAC Corporal - not an Aerobee. The Bumper WAC is often claimed as the first two stage rocket but it wasn't, since the original WAC Corporal itself was actually two-stage with a Tiny Tim solid booster. And in any case the german 1944 Rheinbote artillery rocket was four stage! As a matter of fact it had a somewhat higher top speed than the A4 (V 2) and if the germans ever launched one straight up it was probably the first thing to reach space. tty |
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Jan 3 2006, 11:28 PM
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#19
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Senior Member Group: Members Posts: 3419 Joined: 9-February 04 From: Minneapolis, MN, USA Member No.: 15 |
QUOTE (Bob Shaw @ Jan 3 2006, 07:40 AM) ...Shuttle ETs have gone into orbit several times, but following an orbit which has a perigee below the surface of the Earth (that's why the OMS fires after ET Sep, to circularise the orbit of the shuttle itself). That used to be the case. But over the past several years of Shuttle flight operations, more and more of the launches are "SSME direct-to-orbit", in which the entire stack -- orbiter *and* ET -- are placed into a stable (albeit somewhat low) orbit. No OMS burns required during the first orbit to maintain a safe orbit. This started when the Shuttle needed to get the maximum cargo possible up into the ISS orbit. Adding some SSME delta-V made it possible to get those big components, like Destiny and the solar arrays, up to ISS. -the other Doug -------------------- “The trouble ain't that there is too many fools, but that the lightning ain't distributed right.” -Mark Twain
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Jan 4 2006, 03:20 AM
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#20
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Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
QUOTE (tty @ Jan 3 2006, 05:27 PM) The second stage of the Bumper WAC was a WAC Corporal - not an Aerobee. The Bumper WAC is often claimed as the first two stage rocket but it wasn't, since the original WAC Corporal itself was actually two-stage with a Tiny Tim solid booster. And in any case the german 1944 Rheinbote artillery rocket was four stage! As a matter of fact it had a somewhat higher top speed than the A4 (V 2) and if the germans ever launched one straight up it was probably the first thing to reach space. tty Correct me if this is apocryphyl, but didn't von Braun say "Today the spaceship was born" after the first successful V-2 launch in 1942? -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
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Jan 4 2006, 03:34 AM
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#21
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Member Group: Members Posts: 194 Joined: 8-February 04 Member No.: 10 |
[quote=ljk4-1,Jan 4 2006, 03:20 AM]
Correct me if this is apocryphyl, but didn't von Braun say "Today the spaceship was born" after the first successful V-2 launch in 1942? It was said by Dornberger: http://www.donaldedavis.com/PARTS/V-2.html Don |
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Jan 4 2006, 03:54 AM
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#22
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Member Group: Members Posts: 903 Joined: 30-January 05 Member No.: 162 |
I probably won't field any questions as to how I know this, but near the earth's surface where the atmosphere is densest, a 'typical' manhole cover, dropped edge on from a height of roughly 100 feet is aerodynamically stable till impact with a cement sidewalk.
Upon emerging from the hole, if the cover can be shown to have been edge on to the oncoming slipstream, might there be hope that a significant fraction of it survived to 200 km? |
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Jan 4 2006, 07:13 AM
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#23
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Member Group: Members Posts: 688 Joined: 20-April 05 From: Sweden Member No.: 273 |
What is the stagnation temperature in front of a generic manhole cover moving at 60 kms-1 through a standard atmosphere? The answer doesn't seem to be in the literature. Do we have a good aerodynamicist among the members? A ballpark guess would be well over 10,000 K.
tty |
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Jan 4 2006, 10:06 AM
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#24
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Senior Member Group: Members Posts: 1870 Joined: 20-February 05 Member No.: 174 |
"What can you say about chocolate-coated manhole covers?"
<grin> What's that line from? |
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Jan 4 2006, 05:39 PM
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#25
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Senior Member Group: Members Posts: 3419 Joined: 9-February 04 From: Minneapolis, MN, USA Member No.: 15 |
Ed, that's a Larry Niven short story, called (IIRC) "What Can You Say About Chocolate-Covered Manhole Covers?"
-the other Doug -------------------- “The trouble ain't that there is too many fools, but that the lightning ain't distributed right.” -Mark Twain
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Jan 4 2006, 05:57 PM
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#26
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Member Group: Members Posts: 688 Joined: 20-April 05 From: Sweden Member No.: 273 |
QUOTE (edstrick @ Jan 4 2006, 12:06 PM) "What can you say about chocolate-coated manhole covers?" "It's the only thing on this world that we know we can eat" tty |
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Jan 5 2006, 08:14 AM
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#27
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Merciless Robot Group: Admin Posts: 8783 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
QUOTE (tty @ Jan 4 2006, 10:57 AM) "That one fell pretty flat. What can you say about chocolate covered manhole covers?" -------------------- A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
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Jan 5 2006, 08:28 AM
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#28
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Senior Member Group: Members Posts: 1870 Joined: 20-February 05 Member No.: 174 |
DVandorn wins the keg of Geritol Beer for getting the answer., and without checking the text (20+ years since I read it), I believe that's the last or one of the last lines in the story that TTY posted. <grin>
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Jan 26 2006, 05:28 AM
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#29
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Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
-------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
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Feb 9 2006, 02:00 PM
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#30
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Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
Includes discussion of the fact that no one actually said "Goldstone has the bird!" in regards to the launch of Explorer 1 in 1958.
Apocrypha now: no go for seven orbits --- One of the commonly-accepted "truths" of the history of the American space program is that a potential heat shield problem caused John Glenn's historic Mercury flight to be cut from seven orbits to three. Dwayne Day digs into the historical record to expose that myth and show that Glenn's flight was intended to be three orbits all along. http://www.thespacereview.com/article/550/1 -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
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