In 1955, a group of scientists and engineers at Los Alamos National Laboratory were given the task of reducing the amount of radioactive material expelled into the atmosphere resulting from a nuclear testing. Astrophysicist Robert Brownlee was a principal participant in these tests, named project Bernalillo after a New Mexico county near Los Alamos.
Dr. Brownlee and his team were testing the feasibility of moving nuclear testing underground. In order to achieve a number of scientific objectives, they needed to explode several nuclear devices underground. Doing so involved building the equivalent of a giant, atomic-powered potato cannon. The cannon was a 400-foot-deep well lined with thick steel pipe, capped by a steel plate instead of a potato, and powered by a nuclear bomb instead of a squirt of hairspray.
Forty stories below the scrubby tangle of mesquite trees and creosote on the desert surface, researchers tried to determine if they could test the effects and design of nuclear devices while reducing the release of radioactive materials into the atmosphere to a minimum, maybe even completely.
The Bernalillo team placed a small (by high-energy physics standards) nuclear device in the steel well and capped the well off with a big steel manhole cover. The four-foot-diameter steel manhole cover was four inches thick and weighed in the neighborhood of half a ton.
This puny nuclear device had the explosive equivalent of less than one kiloton of high explosive. However, small in nuclear terms is still incredibly large. The effects of letting lots and lots of nuclear energy loose are sometimes hard to predict. To understand what happened when the device was triggered, the Los Alamos team utilized the scientific method. They started with a hypothesis and then assembled an array of state-of-the-art measuring equipment to test it.
The scientists working on the Bernalillo series of test shots were trying to figure out what happens during the few micro-moments of the nuclear explosion. The Los Alamos team wanted to know what kind of nuclear particles were emitted, how many there were, and most importantly, were they went. The data needed to collect had to be measured in the first few shakes after the explosion begins. (A “shake” is the amount of time it takes light to travel 10 feet. Since light travels at around 186,000 miles per second, that makes a shake an exceedingly short time interval.)
The scientists put all sorts of detectors and sensors in and near the well. They also placed high-speed cameras some distance from the top of the well to film the explosion. Normal cameras take about 16 frames of film every second. The high-speed Los Alamos cameras were 10 times faster.
When the device was triggered, the scientists got a bit more than they bargained for. The bomb emitted high-energy particles of light, called photons. Within a few shakes, the photons, or in Alamos lingo, the “shine,” bombarded the steel pipe, vaporizing it into superheated iron gas. About three hundreds of a second after detonation, the shock wave of gas, light and radiation blasted against the steel cover plate at the top of the well.
The high-speed cameras recorded the blast effect on the plate. In one frame the plate is there. In the very next frame, 1/160th of a second later, it is gone. Where did the four-foot diameter, heifer sized steel plate go? The area was searched carefully, but the plate wasn’t found. In fact, in the 40-plus years since project Bernalillo, no trace of the plate has ever been found, anywhere.
The project team felt they knew where the plate went. Prior to the actual test, Dr. Brownlee’s boss asked him what would happen to the plate covering the test hole. He thought about it for a while. “I guess I don’t really know,” said Brownlee. “Find out,” said the project director.
Brownlee performed some preliminary calculations. Based on the expected bomb, yield, the shape and depth of the test hole, and so forth, he figured the initial velocity of the plate would be somewhere in the neighborhood of 41 miles per second. That’s moving mighty fast. He made many slide-rule calculations and reported back to his director. The manhole cover would probably wind up on a collision course with the distant stars, shoved by a nuclear push through the earth’s atmosphere and into outer space.
In 1687, Isaac Newton figured out some interesting things about gravity and velocity. He deduced that there is one particular speed. One where if you throw something hard enough and fast enough, you can make it through the gravitational attraction of the earth and break free into outer space. Newton called this speed “escape velocity,” and on Earth this is calculated to be just a hair less than seven miles per second. When the Bernalillo team calculated the plate’s velocity just after detonation, they estimated that it was in the rough neighborhood of five times escape velocity! Even taking into account possible assumptive errors and other unknowns, it seemed likely that the plate was traveling well above the speed required to escape the gravitational force of earth.
To test the validity of Brownlee’s calculation, other Los Alamos scientists reviewed the film from the high-speed cameras. Upon review, they found the plate was present in one frame of the high-speed film and gone in the next. They factored in what they knew about the film speed and the field of view of the camera. Based on the photographic evidence, the scientists felt a strong case could be made that the half-ton steel plate was moving faster-in fact, much faster- than escape velocity.
A few years later, in 1959, a team of Soviet scientists launched what they claimed to be the first man-made object into outer space, the satellite Sputnik. Many people at Los Alamos think Sputnik was merely the second object to travel to outer space, preceded by a full two years by an American made manhole cover.
I for one think that this is really cool! The first man-made oblect in space could have been launch by a spud gun! Please share your thoughts.
Edit: Dang! I still only got 5 Spudbux for typing all that, oh well
LOL!
or into orbit 