Utne Blogs > Science and Technology

Marty McFly Had To Be Rich

by Staff


Tags: Space Exploration, Time Travel, Space, Future,

DelorianFrom a physics standpoint, time travel is entirely possible, according to an article in Cosmos Magazine. All you need is a really fast space ship and knowledge of Einstein’s Theory of Special Relativity.  Financially, however, it’s still totally unviable.

Theoretically, if a person were to orbit the Earth at 161,556 miles per second for one full year, during the same time, two years would have passed on Earth. That would mean the person would have traveled a year into the future. The problem is that to travel that fast for that long would require about 30 trillion gigajoules (GJ) of kinetic energy. At over $9 per GJ, the bill would total around $27 trillion. So for Back to the Future to become a reality, Marty McFly would have to be a very rich man.

Erik Helin 

Image by Valerie Everett, licensed under Creative Commons.

Correction: The speed was originally identified in miles per hour. It has been corrected to read miles per second.
norman gravely
2/28/2008 10:34:40 AM

have you no faith in the flux capacitor? LOL


larry letich
2/27/2008 4:35:44 PM

Can Utne please be more diligent about fact-checking its science bloggers? Anyone who has the professional knowledge to write about physics knows that light travels at approximately 186,000 miles per *second,* not per hour. I recall learning this in grade school, folks, or at least middle school. You should have, too. As for "time travel," yes, time moves more slowly the faster you are moving -- but you're still moving forward. Einstein's Theory of Special Relativity does not offer any way to go back in time the way Marty McFly did -- not even a single minute.


bill webb_3
2/26/2008 10:05:29 PM

Theoretically, if a person were to orbit the Earth at 161,556 miles per hour for one full year, during the same time, two years would have passed on Earth. Oops. One presumes you're shooting for about 9/10ths of the speed of light (C), which would be required in order for a 50% time reduction. That would be about 161,566 miles per second . That speed exceeds the estimated escape velocity from the Milky Way galaxy (c. 200 miles per second -- no one is sure, because we don't know the total mass of the galaxy) by at least three orders of magnitude. Even 161,556 miles per hour is nearly 9 times the Earth's escape velocity. It's impossible to travel at an appreciable percentage of C and remain anywhere near the Earth.