A new space odyssey beckons; Manned space exploration...
True or False: We Can Make it to Mars and Back
July 20, 2009 -- We recently heard a radio columnist talk about the impossibility of a manned mission to Mars. He said the voyage would take years, and that long periods without gravity create serious health problems for astronauts..
Any space vehicle you've ever seen, and which can be provided with a continuous thrust of one Earth gravity (one G), will achieve near lightspeed in one month. So Google the distance between Earth and Mars, divide it by 2/3 of the velocity of light, and provide yourself with a rough estimate of how long the journey will take. And the zero-G health problem? It doesn't exist. Since the accelleration we're talking about generates the same amount of force every human body feels on this planet, one gravity, there is no gravity health problem inside such a ship.
What you just read is physics. It cannot be questioned by any scientist. They can quibble about the "weight" (actually "mass") of the vehicle (thus, the fuel-generated thrust per mass unit of the ship required to overcome inertia, which even sitting on the ground is a measurment related to direction, etc., etc.), but not the principle involved. Continuous thrust of one G in outer space will get your SUV to near lightspeed in a month.
So where do we get the fuel to accomplish that? Will liquid oxygen or hydrogen burning for a month do it? Yup, but the thrust numbers you get from that stuff, per unit/volume/mass of that kind of fuel, would require a gas tank the size of Vermont.. It would take a gigantic chunk of that kind of fuel just to get the contraption moving. You could do it with a steam engine, but where would you get the coal? A nuclear rocket would be one answer to the problem. A few pounds of that produce enough steam power in a nuclear submarine to go around the world without surfacing. Then, there's the stuff the universe is made of. A great many modern physicists say that our galaxy spins faster than it should, based on the quantity of mass astronomers can see through their telescopes. There's stuff floating out there that is invisible. That is why legions of these scientists have decided the "missing mass" should be called "dark energy and matter." The dark energy seems to be the largest item. We have read reports that those two were predicted by Albert Einstein. Then, they were rejected by Albert Einstein.
Talk about ironic humor. Remember the joke? "Yes, I have made a mistake in my life. In 1954 I thought I was wrong about something, but it later turned out that I had been right." This is literally what happened to our pal, Al. He wanted the universe to stand still, so dreamt up a force to hold it in place. He called it his "cosmological constant." Later, he called it the biggest mistake of his life. Later, scientists discovered that it sort of existed.
It seems that either gravity has gone soft, or some other force is messing with the universe, these days. This is the conclusion since somebody noticed that the Big Bang original explosion which started the universe expanding is not the only wind in the cosmic willows. The rate of expansion is increasing.
Perhaps this dark stuff has something to do with it. At any rate, the galaxies spin too fast for the mass that can be observed. Dark matter and energy make the numbers work out perfectly. Quite likely, this missing stuff, whatever the hell it actually is, must kiss Albert Einstein's butt. It must exist/operate/behave within the framework of the most famous equation in the history of Earth -- E=MC2. The energy (power/force) potential in every gram of dark matter, just like in every gram of matter we can see, is a number that is equal to the amount of it times the velocity of light squared. So, just get out your hand calculator and multiply 186,000 miles per second times itself. Then multiply that number times the grams of plutonium or goose grease or dark matter you have in the rocket's gas tank.
That final number, which should take up half or more of the page to write down is how many (watts/pounds of thrust/whatever) of energy that the rocket will throw in the opposite direction while your ship heads for the Red Planet. (Assuming dark matter's reaction to the laws of phyics isn't sign-opposite. If it is, the way to use it will involve research by scientists from Disneyland.)
A few pounds of uranium wiped out two cities in Japan, ending the Second World War. Send a controlled explosion like that out the tailpipe of a space ship for a month, and you will be well on your way to dining at the Mars Bar and Grille.
The point is, just based on known physics, some kind of "fuel" is available either here on Earth or out there in space, and that fuel can be used to drive a spaceship to a large fraction of the velocity of light. And at that speed, a space ship would get to Mars and back in about the same amount of time it takes the average American to understand the remote control functions on his DVD. Say, about the time between Easter and Thanksgiving. I may be off by a couple of months, here, but that doesn't matter.
We'll find a way to go, and go quickly. Forget colony ships and whirling gizmos that use centrifugal accelleration to replace gravty effects on the human body. Once we find the fuel and understand the physics of it, the engineers will do their thing and we'll be off to go where no man has gone, before.
© 2009 Oregon Magazine