Beyond Mars

I read a review of Louis Friedman’s new book, Human Spaceflight From Mars to the Stars. (Friedman is the executive director emeritus of The Planetary Society, which he co-founded with Carl Sagan and Bruce Murray in 1980.)

Friedman is optimistic about human space exploration, but he is quite certain that humans will not travel beyond the orbit of Mars in any significant way.

He says that human space travel beyond Mars is too expensive and is unnecessary; we can send machines to gather data, and virtual reality can give us the illusion that we have made the trip. He also says that space colonies – cities in space orbiting the sun – are impractical and unnecessary, a science-fiction idea that is not in our future.

I was at once reminded of Arthur Clarke’s First Law of Prediction: When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.

I don’t know what time scale Friedman has in mind. If it’s the next 20 years, then he’s very probably correct. If it’s the next 1000 years, then he’s very probably wrong.

If a human of 300 years ago had been asked about the feasibility of going to the Moon, or of building a city full of skyscrapers, or even of building a network of paved roads like America's interstate highway system, he would surely have thought all of the ideas were far-fetched and unlikely to ever become reality.

Sending humans to the Moon? Not only impossible but completely unnecessary – until the invention of rocket technology and computers made it possible and a space-race made it necessary. A city of skyscrapers? Impossible – until inventions like structural steel, elevators, and electric lighting made it possible. A continent-wide system of paved highways? Impractical and unnecessary (for horses) until mass-production of motor vehicles made paved highways essential.

It’s impossible to predict future technologies and what they may enable humanity to do. It’s impossible to predict what our descendants may want to do or what they may need to do. However, we do know one aspect of the future: some of the things our descendants will do will be, to our eyes, indistinguishable from magic.