Possible Challenger To Sputnik, manhole first manmade object in space? |
Possible Challenger To Sputnik, manhole first manmade object in space? |
Jan 3 2006, 03:42 AM
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Newbie Group: Members Posts: 4 Joined: 18-April 05 Member No.: 250 |
I was browsing around and found some intresting articles about there is some debate whether or not a metal cover for a underground nuke test a few months before Sputnik made it to space or not. Pictures from the test (launch??) give a lower bound of its velocity at 56km/s. the main argument agianst is that it would have blead off the speed in the atmosphere. anyways, kinda cool
http://nuclearweaponarchive.org/Usa/Tests/...ob.html#PascalB http://nuclearweaponarchive.org/Usa/Tests/Brownlee.html what do you think? m |
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Jan 3 2006, 11:57 AM
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#2
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Founder Group: Chairman Posts: 14434 Joined: 8-February 04 Member No.: 1 |
This item might have made it into space - but never into orbit.
Ignoring the fall off of gravity, and ignoring air resistance, getting into orbit is a two fold issue. Getting high, and getting fast. Say you need 200km and 7500 m/sec The pot.energy of, say, 1kg @ 200km is 200,000 J The Kinetic Energy of that 1kg doing 7500 m/s (orbital velocity) is 28,125,000 J Those are the two things you need to add to something to get it into orbit. So even if they gave it enough shove to overcome friction, and it survived the massive heating, it might have got into space, but it would never have got into orbit Doug |
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Jan 3 2006, 01:40 PM
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Senior Member Group: Members Posts: 2488 Joined: 17-April 05 From: Glasgow, Scotland, UK Member No.: 239 |
QUOTE (djellison @ Jan 3 2006, 12:57 PM) This item might have made it into space - but never into orbit. Ignoring the fall off of gravity, and ignoring air resistance, getting into orbit is a two fold issue. Getting high, and getting fast. Say you need 200km and 7500 m/sec The pot.energy of, say, 1kg @ 200km is 200,000 J The Kinetic Energy of that 1kg doing 7500 m/s (orbital velocity) is 28,125,000 J Those are the two things you need to add to something to get it into orbit. So even if they gave it enough shove to overcome friction, and it survived the massive heating, it might have got into space, but it would never have got into orbit Doug Doug: To have an orbit which lasts for more than one pass, you need two impulses, too - one to raise the perigee from sea-level up to something which doesn't intersect the ground (or the atmosphere). 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). Bob Shaw -------------------- Remember: Time Flies like the wind - but Fruit Flies like bananas!
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Jan 3 2006, 05:50 PM
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#4
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Member Group: Members Posts: 688 Joined: 20-April 05 From: Sweden Member No.: 273 |
QUOTE (Bob Shaw @ Jan 3 2006, 03:40 PM) Doug: To have an orbit which lasts for more than one pass, you need two impulses, too - one to raise the perigee from sea-level up to something which doesn't intersect the ground (or the atmosphere). 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). Bob Shaw 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 |
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Jan 3 2006, 06:40 PM
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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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