"Would you ever sign up for a trip to Mars?"

The arching sky is calling

Spacemen back to their trade.

All hands! Stand by! Free falling!

And the lights below us fade.

Out ride the sons of Terra,

Far drives the thundering jet,

Up leaps the race of Earthmen,

Out, far, and onward yet--

We pray for one last landing

On the globe that gave us birth;

Let us rest our eyes on fleecy skies

And the cool, green hills of Earth.

Robert A. Heinlein, The Green Hills of Earth 

It used to be that I depended on television for weather reports, but thanks to the Internet I just check online with The Weather Network whenever I need information more explicit than what I can determine by looking out the window. The Weather Network website does its best to be more than just a list of temperatures and weather predictions by adding in things like trivia, photos from users, videos of extreme weather, and surveys – which often have nothing to do with weather. As an example, a recent survey asked visitors to the site if they would be willing to “Sign up for a trip to Mars” with four possible answers.

I was pleased to see that 31% of the respondents would be willing to go into space, but a little surprised to see that 3% would sign up exclusively for a one-way trip. (Just for the record, I fall into the “Sure!” group, and I honestly can’t say that I thought about it in terms of whether it would be impossible to return.) I realize that this small percentage probably viewed the Martian odyssey as a chance to leave behind the petty concerns of earthbound existence for a life on the frontier, without ever looking back.  That aside, would Martian colonists have to accept that it was a one-way ride with no chance to return to Mother Terra?

Depending on the relative orbital positions of Earth and Mars, and how much fuel you’re willing to burn on the trip, going to Mars could take as little as 130 days or as long as 300. Let’s pick a median and say 210 days, or about seven months. That doesn’t sound like a one-way trip to me. It’s a long haul, admittedly, and 130 days sounds a lot better, but provided that there’s adequate living space, entertainment, and perhaps even work of some sort to fill the time, not a deal-breaker in terms of a round trip.

However, this is the sort of schedule that NASA has used for pieces of technology not bothered by boredom, claustrophobia or lack of gravity. If we do a one-G burn to midpoint and then decelerate at the same rate for the second half of the trip, apparently the trip could come in at less than a week. (With some variance in the exact times - see above re: relative orbital positions.) You need a lot of fuel to pull this off, but I’m willing to bet that there’s some kind of compromise between the two extremes of zero and one gravity* that would make this practical in terms of both time and fuel.

This solves two problems - keeping the trip time to a minimum, and reducing the effects of extended exposure to zero gravity.  Given the various health issues suffered by astronauts returning to Earth after 146 days in the zero-G environment of the International Space Station, anything that either reduces the time line or creates the illusion of gravity through acceleration is a good thing.

In the short term, astronauts get their “earth legs” back fairly quickly, but the long term effects will not be known until, well, the long term – retired Canadian astronaut Chris Hadfield will probably be the subject of regular medical scrutiny for the rest of his life in order to determine whether or not his natural span was reduced by his extended exposure to lack of gravity.

As it turns out, we may have already begun the process of colonizing Mars in some small way, albeit accidentally. A recent study conducted by the American Society for Microbiology revealed that there are 377 strains of bacteria that can make it through the sterilization process used on the Curiousity Mars rover before its departure.** This is probably a non-issue: between exposure to vacuum and high UV levels on the Martian surface, it would be a very determined organism that survived the entire process. On the other hand, there are bacteria that thrive in a wide range of environmental conditions, so it wouldn’t take a lot of shelter for a bacteria to make it to Mars alive.

Hmmm…do bacteria mutate? Anybody remember The Andromeda Strain?  Now that I think about it, maybe it is a good idea after all if no one comes back from Mars - just in case.

- Sid

*And if you do a 2-G trip, I bet you can bring it down to a day or two, but first, that would be really fuel intensive, and second, it may not be a great idea to subject the human anatomy to two gravities for that long.

** There is actually a mandate in the UN Space Treaty that stipulates that space missions "shall avoid harmful contamination of space and celestial bodies.”