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Unmanned Spaceflight.com _ Earth Observations _ Possible Challenger To Sputnik

Posted by: PaleBlueDot Jan 3 2006, 03:42 AM

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/Plumbob.html#PascalB

http://nuclearweaponarchive.org/Usa/Tests/Brownlee.html

what do you think?

m

Posted by: tasp Jan 3 2006, 05:26 AM

I would love to see some comments on this by any of the Project Orion folks.

blink.gif

Posted by: nprev Jan 3 2006, 05:46 AM

I don't see any way at all for the plate to survive the friction on the way up, unfortunately. Steel is an excellent conductor, so it was undoubtedly isothermal throughout its brief ascent before abruptly turning into a small cloud of plasma...

laugh.gif ...but what red-blooded guy wouldn't have given his back teeth to be there on that day with the grill fired up and a couple of coolers chock-filled with brewskis? "It blowed up REAL good, Vern!!!!!!" laugh.gif laugh.gif

Posted by: Bob Shaw Jan 3 2006, 11:36 AM

Hmmm... ...first into space?

Well, the WW1 Paris Gun was marginal, but the V2 certainly made it into space. The post WW2 V2 flights by both the US and the Soviet Union, sometimes with upper stages, reached as high as 250 miles (Project Bumper).

As for the first objects to escape from Earth's gravity (but *not* to enter orbit), did not one of the early 50s Project Farside launches propel lead shot at about 30,000 mph, straight(ish) up? I think it was an artificial meteor experiment...

Bob Shaw

Posted by: djellison Jan 3 2006, 11:57 AM

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 smile.gif

Doug

Posted by: Bob Shaw Jan 3 2006, 01:40 PM

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 smile.gif

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

Posted by: djellison Jan 3 2006, 02:12 PM

Oh - I've flown enough Orbiter to understand all that smile.gif What I was trying to demonstrate was the fact that getting high, and getting to orbit, are very very different ballparks smile.gif

Doug

Posted by: ljk4-1 Jan 3 2006, 03:31 PM

Some data on those pellets launched by an Aerobee rocket in 1957:

http://64.233.161.104/search?q=cache:JNWn7c-CV6sJ:clsdemo.caltech.edu/181/01/zwicky.pdf+aerobee+pellets&hl=en


Article with photo of the actual rocket before launch. Page also links to a PDF file article on Fred Zwicky with an image of the pellets being shot into interplanetary space:

http://utenti.lycos.it/paoloulivi/aerobee.html


http://www.astronautix.com/lvs/aerobee.htm

1957 Oct 17 - 5:13 GMT - Launch Site: Holloman . Launch Complex: A. Launch Vehicle: Aerobee. LV Configuration: Aerobee Artificial Meteor.

Meteorites mission Nation: USA. Payload: Metal Pellets. Agency: USAF. Apogee: 80 km.

USAF successfully launched pellets at a speed faster than 15 km/sec (some 3.5 km/sec faster than the velocity necessary to escape from the earth) by an Aerobee rocket to a height of 56 km; the nose section then ascended to a height of 87 km where shaped charges blasted the pellets into space. It is claimed that the Superschmidt Telescope at Sacremento Peak photographed the trajectory with a rotating shutter. These little metal pellets would therefore be the first objects to be shot into interplanetary space, months before the first launch to escape velocity (Luna 1, January 1959). But also see August 1957 nuclear test that may have blasted a manhole cover to escape velocity. References: 91 , 1572 .

Posted by: Bob Shaw Jan 3 2006, 04:20 PM

QUOTE (ljk4-1 @ Jan 3 2006, 04:31 PM)
Some data on those pellets launched by an Aerobee rocket in 1957:

http://64.233.161.104/search?q=cache:JNWn7c-CV6sJ:clsdemo.caltech.edu/181/01/zwicky.pdf+aerobee+pellets&hl=en
Article with photo of the actual rocket before launch.  Page also links to a PDF file article on Fred Zwicky with an image of the pellets being shot into interplanetary space:

http://utenti.lycos.it/paoloulivi/aerobee.html
http://www.astronautix.com/lvs/aerobee.htm

1957 Oct 17 - 5:13 GMT - Launch Site: Holloman . Launch Complex: A. Launch Vehicle: Aerobee. LV Configuration: Aerobee Artificial Meteor.

Meteorites mission Nation: USA. Payload: Metal Pellets. Agency: USAF. Apogee: 80 km.

USAF successfully launched pellets at a speed faster than 15 km/sec (some 3.5 km/sec faster than the velocity necessary to escape from the earth) by an Aerobee rocket to a height of 56 km; the nose section then ascended to a height of 87 km where shaped charges blasted the pellets into space. It is claimed that the Superschmidt Telescope at Sacremento Peak photographed the trajectory with a rotating shutter. These little metal pellets would therefore be the first objects to be shot into interplanetary space, months before the first launch to escape velocity (Luna 1, January 1959). But also see August 1957 nuclear test that may have blasted a manhole cover to escape velocity. References: 91 , 1572 .
*



Great sleuthing!

I always thought it was a balloon-borne launch, and they were lead pellets - isn't it great how the memory plays, er, you know, what's the word?

Things?

Bob Shaw

Posted by: Phil Stooke Jan 3 2006, 05:22 PM

If you can find this:

Zwicky, F., 1961. Possible operations on the Moon. Spaceflight v. 3, no. 5, September 1961, pp. 177-179.

you will see a lunar connection to the pellet 'launch': it was a scheme to get lunar composition data from the spectrum of the impact flash, if one of the pellets could be made to hit the moon. The actual test in 1957 didn't do this, but future attempts might have tried to do so.

Phil

Posted by: tty Jan 3 2006, 05:50 PM

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

Posted by: PaleBlueDot Jan 3 2006, 06:00 PM

QUOTE (djellison @ Jan 3 2006, 04:57 AM)
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 smile.gif

Doug
*


well we know it started fast (<56km/s). im wondering if it some how made it threw atmo (to its advantage, newmexico is pretty high, so it probably started above 5000 feet, and who knows how high it got a free ride from the column of blast air). also, if it couldnt circlulize its orbit, could it still make one orbit without hitting earth?, perhaps if it kept a large amount of its velocity, if it made it past geosynchrnous orbit, would the velocity it had from earths rotation be enough to keep it in orbit?

how do rocks from meteor impacts make it into a stable orbit?

m

Posted by: Phil Stooke Jan 3 2006, 06:09 PM

"how do rocks from meteor impacts make it into a stable orbit?"

They don't. They either escape (like a 'Mars meteorite') or fall back down to make a secondary crater, where that elliptical orbit intersects the surface again.

Phil

Posted by: um3k Jan 3 2006, 06:14 PM

QUOTE (Phil Stooke @ Jan 3 2006, 01:09 PM)
"how do rocks from meteor impacts make it into a stable orbit?"

They don't.  They either escape (like a 'Mars meteorite') or fall back down to make a secondary crater, where that elliptical orbit intersects the surface again.

Phil
*

Then how was the moon formed? huh.gif

Posted by: Bob Shaw Jan 3 2006, 06:36 PM

QUOTE (um3k @ Jan 3 2006, 07:14 PM)
Then how was the moon formed? huh.gif
*


The currently most popular theory involves a glancing impact by a Mars-sized object ('The Big Whack') in which both the proto-Earth and the incoming object were thoroughly heated up and shattered. The Earth collected much of the debris, while the rest, due to the magic of orbital dynamics, managed to whizz off and to form a number of clumps, which fairly soon coalesced into one object, with debris raining down for some time thereafter. This theory neatly explains why Lunar rocks are so similar to Terrestrial ones, but sans volatiles - they all got boiled away. The Earth was sufficiently more massive than the Moon that it could replenish the volatile-depleted surface materials through outgassing, subduction etc, so that we see no signs of the impact on our own planet.

It has one flaw, which is *other* satellites going around other planets, none of which it so neatly explains!

Previous theories tended to see the Moon as a small planet which had somehow been captured by the Earth, but this had many problems too, not least being the similarity of it's composition to that of the Earth, but, again, without volatiles (which are to be expected in quantity on the larger asteroids).

Bob Shaw

Posted by: Bob Shaw Jan 3 2006, 06:40 PM

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

Posted by: BruceMoomaw Jan 3 2006, 07:36 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 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.

Posted by: tty Jan 3 2006, 10:27 PM

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

Posted by: dvandorn Jan 3 2006, 11:28 PM

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

Posted by: ljk4-1 Jan 4 2006, 03:20 AM

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?

Posted by: DDAVIS Jan 4 2006, 03:34 AM

[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

Posted by: tasp Jan 4 2006, 03:54 AM

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?

rolleyes.gif

Posted by: tty Jan 4 2006, 07:13 AM

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. blink.gif

tty

Posted by: edstrick Jan 4 2006, 10:06 AM

"What can you say about chocolate-coated manhole covers?"

<grin>

What's that line from?

Posted by: dvandorn Jan 4 2006, 05:39 PM

Ed, that's a Larry Niven short story, called (IIRC) "What Can You Say About Chocolate-Covered Manhole Covers?"

-the other Doug

Posted by: tty Jan 4 2006, 05:57 PM

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" smile.gif

tty

Posted by: nprev Jan 5 2006, 08:14 AM

QUOTE (tty @ Jan 4 2006, 10:57 AM)
"It's the only thing on this world that we know we can eat" smile.gif

tty
*


"That one fell pretty flat. What can you say about chocolate covered manhole covers?" tongue.gif

Posted by: edstrick Jan 5 2006, 08:28 AM

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>

Posted by: ljk4-1 Jan 26 2006, 05:28 AM

Sputnik-3, its flight and radio systems

http://www.svengrahn.pp.se/radioind/Sput3radio/Sput3radio.htm

Posted by: ljk4-1 Feb 9 2006, 02:00 PM

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

Posted by: BruceMoomaw Feb 10 2006, 05:06 AM

Where the hell did THAT one get started? It was made clear from the very start of the Mercury program that the first two US manned orbital flights (Glenn and Carpenter) would run 3 orbits each.

Posted by: dvandorn Feb 10 2006, 01:09 PM

Bruce, that one got started because of the AZUSA guidance system of the Atlas rocket. The trajectory guys on the first Mercury orbital flight (MA-6, Glenn's flight) were tracking the capsule using the AZUSA system, and their first projection after MECO told them that the capsule's orbit was "safe" (i.e., it wouldn't decay on its own) for at least seven orbits. They called that out and Alan Shepard, at the Cape's CapCom console, passed it along to Glenn.

So, very shortly after orbital insertion, Shepard called up to Glenn, "You have a GO, at least seven orbits."

That call-out had nothing to do with the anticipated length of the mission -- it merely told Glenn that his orbit was high enough that it wouldn't decay naturally before at least the seventh orbit. I believe that this was a planned call-out, and that any value for this call-out greater than three orbits was considered a GO situation.

Since most of the news people covering the flight, and since an even greater percentage of historians who have written about the flight since, didn't have any kind of clue as to how the flight controllers called out their data and how that data was used by all involved, there has been an urban myth that MA-6 was supposed to fly for at least seven orbits. The myth is simply a misunderstanding of the call-out.

-the other Doug

Posted by: ljk4-1 Apr 25 2006, 04:27 PM

"Chronology of Significant Events and Decisions Relating to the
US Missile and Earth Satellite Development Programs - May 1942
to October 1957"

http://www.blackvault.com/documents/dod/readingroom/14/578.pdf

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