- What's the difference between a flying saucer and a flying pretzel?
- Why didn't the aliens in Independence Day have to bother invading Earth to destroy it?
- What's new with warp drives?
- What's the most likely scenario for doomsday?
- Are ESP and telekinesis impossible?
- What do clairvoyance and time travel have in common?
- How might quantum mechanics ultimately affect the fate of life in the universe?
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About the Author
Lawrence M. Krauss is Ambrose Swasey Professor of Physics and Professor of Astronomy and Chairman of the Department of Physics at Case Western Reserve University. He is also the author of two acclaimed books, Fear of Physics: A Guide for the Perplexed and The Fifth Essence: The Search far Dark Matter in the Universe, and over 120 scientific articles. He is the recipient of several international awards for his work, including the Presidential Investigator Award, given by President Reagan in 1986. He lectures extensively to both lay and professional audiences and frequently appears on radio and television.
Read an Excerpt
It's just that in most of my work, the laws of physics rarely seem to apply!
A dark, ominous shadow descends over your house. The furniture starts to rattle, the walls and ceiling vibrate, and you hear a strange whistling in your ears. You rush to the window to see what's causing all the commotion. Only 5,000 feet off the ground, a huge black disk at least 15 miles across floats motionless in the sky, blotting out the sun, darkening the entire neighborhood. You run to the kitchen sink and splash cold water on your face. Surely this can't be happening! Back to the window once more, and the massive object is still there. You scurry out to the garage to get away, then you remember something. Hurrying back to the house, you pick up the phone to call your daughter's school, but the line is dead. You lose bladder control. The realization terrifies you. Aliens have arrived! As you begin to black out, your last thought is, I am about to become toast!
Hold on! While F14s or computer viruses or even H. G. Wells's microbes might not be able to protect us from the sheer terror generated by the attack of a 15-mile-wide floating saucer, Isaac Newton would--sort of. Newton's laws would ensure that you'd probably be dead before you had time to get terrified. Even 350 years after the fact, Hollywood still has to get past Newton before it can indulge in all the fancy stuff. Alas, the aliens piloting the Mother Ship in the blockbuster Independence Day seem to have skipped that semester back home. . . .
What instead might actually transpire if we were visited by the Mother Ship and her children reads more like a scenario for theSalem witch trials.
Death by Drowning
A Mother Ship full of aliens bent on ending life on Earth may not need to send out a squadron of huge flying saucers in order to destroy our major cities. Long before the first shadow fell on the Empire State Building or the Hollywood sign, New York might be underwater and Los Angeles could be leveled by earthquakes. Early in Independence Day, the telemetry tracking the approach of the Mother Ship reveals that it is almost 1/4 the mass of the Moon. Before it releases its squad of death saucers, the mammoth ship pulls into a geostationary orbit above the Earth--the same sort of orbit the U.S.S. Enterprise uses to visit a new planet. In such an orbit, a spacecraft or a satellite moves at the same rate as the planet rotates, so that it always stays directly above the same spot on the planetary surface. The large communication satellites that transmit our international messages, as well as the network of Global Positioning navigational satellites that guide our airplanes and well-equipped trekkers (the terrestrial wilderness type), sit in such orbits.
Newton's law of gravity determines how high such an orbit must be, regardless of the object's mass. It is one of the many miracles of the law of gravity that any object, no matter how heavy, must orbit at exactly the same speed as any other object at the same distance from Earth. (If that weren't the case, NASA would have to design a different trajectory for every space shuttle, depending upon the weight of the astronauts inside.) The distance from Earth for an object in geostationary orbit is about 22,500 miles, or almost 1/10 the distance from Earth to the Moon. At 22,500 miles up, the gravitational attraction on the Earth of an object the mass of the Moon would be 100 times stronger than the Moon's gravitational pull; since the Mother Ship is 1/4 the mass of the Moon, its gravitational pull on the Earth would be 25 times that of the Moon!
What would this do? Well, one effect might well be to close down Wall Street, because much of New York City would probably be awash. The tidal forces provoked by an object as massive as the Mother Ship would cause a catastrophic rise in sea level in various places on the Earth. At the same time, the unaccustomed tidal stresses on the Earth's crust would undoubtedly induce earthquakes and volcanic eruptions in sensitive areas around the globe. Moreover, the very motion of the Earth through space would be affected, producing unpredictable effects, including possible climatic variation. When an object as heavy as 1/4 the mass of the Moon is in close orbit above the Earth, it causes the Earth to move back and forth in response--once again, because of gravity. Adding a third massive body, with its additional gravity, to the Earth-Moon system would change the system's dynamics in possibly chaotic ways.
Indeed, if the evil aliens were particularly patient--and why shouldn't they be?--they might choose to orbit the Earth in the direction opposite to its present direction of rotation. The tidal pull of the Mother Ship would then slowly serve to brake the Earth's rotation rate, lengthening the day or getting rid of it all together! In just such a way, the length of the Earth's day has been slowing due to the Moon's pull. Eventually (on a cosmic timescale), the Earth's rotation period would precisely match the orbital period of the Moon, so that one Earth day would be almost a month long. Imagine how hungry you would get between lunch and dinner.
Whether or not its crew chooses the slow route or the fast one, the Mother Ship could wreak devastation on Earth by astute choice of orbit, without doing anything more than being there-- much easier than risking battle with terrestrial aircraft and missiles.
Beyond Star Trek. Copyright © by Lawrence M. Krauss. Reprinted by permission of HarperCollins Publishers, Inc. All rights reserved. Available now wherever books are sold.
Most Helpful Customer Reviews
I've enjoyed these books from the very first one. My only complaint is not the author's fault, but rather the ebook publisher's: this copy is poorly fomatted. Occasional spelling and grammar errors indicate to me this copy is little more than an OCR scan with little clean-up.