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Eroica
2005-Apr-03, 03:01 PM
Quick: what was the first man-made object to be placed in orbit? If you said Sputnik 1, then guess again! :)

I came across these statistics in a recent article in a newspaper, so I don't know how accurate they are. But I think they're quite interesting.

4,500 - launches since the start of the Space Age

26,000 - observable objects placed in orbit

9,000 - of these have diameters greater than 10cm

< 200 - currently operational satellites

100,000 - objects in orbit with diameters between 1cm and 10cm

Several Million - objects in orbit with a diameter of about 1mm

10 kps - average relative velocity of an impact with debris in LEO

Once every 15,000 years - chances of a satellite 100 square metres across, orbiting at an altitude of 400km, hitting an object 10cm across

Once every 10 years - chances of a satellite 100 square metres across, orbiting at an altitude of 400km, hitting an object 1cm-10cm across

1957 Alpha 1 - jettisoned portion of the rocket that launched Sputnik 1 and the first man-made object to be put in orbit

sarongsong
2005-May-30, 10:20 PM
"... a representation of the space debris in low Earth orbit..."
http://starbulletin.com/2005/05/30/news/art6a.jpg (http://starbulletin.com/2005/05/30/news/)

George
2005-May-30, 11:33 PM
And to think there were no man-made objects in space prior to 1957.

Fritz Zwicky was the first, apparently. to get something up there. It was a bullet or some shrapnel, I think.

mickal555
2005-May-31, 02:21 AM
"... a representation of the space debris in low Earth orbit..."
http://starbulletin.com/2005/05/30/news/art6a.jpg (http://starbulletin.com/2005/05/30/news/)

That isn't to scale though so there's alot of space still up there- I think we should crash it all back down again- make for some interesting viewing...

Tacitus
2005-May-31, 04:00 AM
Some interesting links:

From NASA - more than you could possibly want to ever know about debris in orbit:
http://ston.jsc.nasa.gov/collections/TRS/_techrep/TP-1999-208856.pdf

Proposal for a pulsed laser to destroy debris in orbit:
http://phippsd.best.vwh.net/orion.htm

The UN is concerned:
http://www.oosa.unvienna.org/Reports/AC105_681E.pdf

Eroica
2005-May-31, 11:49 AM
Fritz Zwicky was the first, apparently. to get something up there. It was a bullet or some shrapnel, I think.
I think he was the first to get something into Sun-Orbit (in 1957, just 12 days after Sputnik was launched). I don't believe any of his earlier experiments with V-2 rockets after the war succeeded in putting anything into Earth-Orbit. :-k

George
2005-May-31, 01:25 PM
Fritz Zwicky was the first, apparently. to get something up there. It was a bullet or some shrapnel, I think.
I think he was the first to get something into Sun-Orbit (in 1957, just 12 days after Sputnik was launched). I don't believe any of his earlier experiments with V-2 rockets after the war succeeded in putting anything into Earth-Orbit. :-k
This might be a good question. I have not read much about it but it seems like he sent some metal up and used an explosion to accelerate shrapnel. If so, maybe some chunks did not escape Earth's oribit. Of course, it probably would not be still up there, I suppose. I find his effort peculiar and almost juvenile, a showboat stunt similar to something I would try to pull :)

eburacum45
2005-May-31, 02:14 PM
Some mention of Zwicky here;
http://www.mail-archive.com/meteorite-list@meteoritecentral.com/msg20391.html

this also includes the orbital manhole cover myth; a plug which was propelled at escape velocity by a nuclear explosion...

George
2005-May-31, 03:54 PM
Some mention of Zwicky here;
http://www.mail-archive.com/meteorite-list@meteoritecentral.com/msg20391.html

That is a fair example of the sites I've found, though I haven't looked hard.



But the 1946 experiment undoubtedly
had both escape velocity particles and orbiting
particles, so if pellets count as "spacecraft", Zwicky
was beat too.
No mention was given of the '46 experiment. I vaguely recall a 1946 American V2 attempt at this but I read it had failed. I assumed failure meant no metal into space.

So, who was first? #-o

Glom
2005-May-31, 04:03 PM
I think we should crash it all back down again- make for some interesting viewing...

Are you crazy? Do you have any idea how much the global warming alarmist would get their pants on fire over all those objects having their kinetic energy dumped into the atmosphere?

mickal555
2005-Jun-01, 02:38 AM
I think we should crash it all back down again- make for some interesting viewing...

Are you crazy? Do you have any idea how much the global warming alarmist would get their pants on fire over all those objects having their kinetic energy dumped into the atmosphere?
huh?

How could that effect global warming anymore than you standered once a month house sized meteor?
I'd say theve got their kninekers in a knot