Manhole Covers in Space

Strange Horizons ^ | 6/27/2009 | By Debbie Moorhouse

[ErnstStavroBlofeld]

A question on the letters page of the September 2002 issue of Fortean Times -- a British magazine which covers fringe science or "Fortean" subjects -- piqued my interest. Was it true that a manhole cover, accidentally blasted upwards at escape velocity during the American nuclear tests in the 1950s, was in fact the first manmade object in space, beating Sputnik 1 by a long way? Or was it just an urban myth?

The Internet is the natural home of the urban myth: the two could have been made for each other. The question therefore was: could it find room for the truth as well?

It's often thought necessary to give dire warnings about not trusting anything you see or read online. I would go further -- don't trust ANY source implicitly. The advice my history teacher gave me all those years ago seems to me to apply as well to the net as to anything else: When considering the validity of a source, ask yourself these questions: who created it, when (especially in relation to the events described), and why? With this in mind, and convinced that the story had to be nonsense, I nonetheless made some enquiries on the Internet, using Google as my base.

Here's what I found out.

"The first man-made object sent into space was a manhole cover which by now has travelled well past Pluto!" (SAAO). Sadly, the link promising the 'full story' is broken. Isn't it always the way?

[ErnstStavroBlofeld]

This is a map of all the seismic stations in Nevada. As you can see, they have them all over the place. If it came down one of these many stations would have pick it up

[ErnstStavroBlofeld]

We are talking about it right? Myth vs Reality. We are flushing out the truth

[MaxMax]

What can you say about chocolate manhole covers?

You're this close to the best Gerbil joke in the world

[HiTech RedNeck]

But if it sailed out of the region altogether....?

[ErnstStavroBlofeld]

Then the Nevada Seismic Network will not pick it up.

[dr_lew]

An escape velocity in ground level atmosphere would mean instant plasma, no?

When I said "inconceivably", I was speaking from a personal perspective :-) But we may apply the criterion of mass displacement. The object will collide with a volume of air equal to its own weight within a distance 1,000 times its own width times its specific gravity. A manhole cover presents a difficult shape, but I think we can say this effective distance will be less than a kilometer. So within that distance it has to give up half its speed, on momentum considerations, and thus three quarters of its kinetic energy.

Now it's just a question of comparing its kinetic energy per unit mass with the specific heat of steel, say 500 J/kg/C.

An escape velocity of 11000 m/sec gives 60e6 J/kg, which is enough energy to raise the temperature of a steel object by more than 100000 K. So yeah, it looks like we're talkin' instant plasma here.

[ErnstStavroBlofeld]

Here is some info on the Nevada CEMP stations:

A network of CEMP stations located in selected towns, communities, and ranches of Nevada and Utah within 240 miles from the NTS are operated continuously. The stations monitor gross alpha and beta radioactivity, penetrating gamma radiation, gamma radiation exposure rates, and meteorological parameters using automated weather instrumentation. Prior to 1992, when there was an active underground nuclear weapons testing program on the NTS, the CEMP stations also monitored for radioactive noble gases. Occasionally, very small, harmless amounts of these noble gases were detected at the Rachel or Lathrop Wells CEMP stations. The noble gases were the result of operational releases occurring on the NTS or late-time seeps following the detonation of an underground nuclear test.

[knarf]

"We are flushing out the truth"

God, I hope not .... let's flesh it out, instead.

[ErnstStavroBlofeld]

That is fine with me

[Mount Athos]

laugh of the day

[Heatseeker]

Actually it's What Can You Say About Chocolate Covered Manhole Covers?. Niven was/is an underappeciated humorist: I laughed over Man of Steel, Woman of Kleenex for a week. There's a funny video made from the story here.

[HiTech RedNeck]

And also, how might it fall, even in the desert? If it had significant spin, it would land flat and gently, like a Frisbee, and skid along the sand a fair distance before coming to a halt. That would not produce much of a seismic signature.

[2111USMC]

Someone could get hurt.

[HiTech RedNeck]

For the same reason, railgun rocketry at the surface of the earth will never be feasible for getting a craft into outer space. Escape velocity will burn up the object unless it is first brought into a region with sufficiently thin air.

[junkman_106]

I told this story to my mother as she had a very high top secret clearance after the war (WWII) and worked on projects like this. She said “You’ll put your eye out!”!

[Paradox]

But I would also expect a hurtling disc would have rapidly begun to fly like a Frisbee,

Unless you impart a substantial initial spin, a Frisbee is horribly unstable. Imagine that same Frisbee, launched vertically. Heck, go try it yourself, see if you can make it go up more than a couple of feet before it starts tumbling wildly.

No, I'm afraid that thing vaporized soon after its launch. Think of this, say the calculations give it 2x escape velocity. Thats nearly 50,000 MPH. Re-entry velocity is about 18,000 MPH. Much more energetic, plus its slamming straight into the thick atmosphere at the surface, not the thin stuff re-entry vehicles get to go through first. I imagine that thing turned into liquid fast, and then into a cloud of iron vapor.

[raybbr]

Were those sensors in place in the ‘50’s?

[Lonesome in Massachussets]

I agree with you. The Pluto part is impossible. These tests were done out in the DOE Nevada Site.

Hey, under the new International Astronomical Union (IAU) rules, shouldn't we be arguing about the orbit of Neptune?

[Hot Tabasco]

a manhole cover

Obviously headed for Uranus.....

[ExGeeEye]

...a ballistic launch into space from a canon...

:)