Tuesday, March 5, 2013

Around Mars in 500 Days

Dragon Capsule, courtesy Space X
First it was the Ansari X Prize and Spaceship One, then Red Bull's sky-dive from space and Google's Lunar X Prize. Now millionaire Dennis Tito wants to send a privately funded mission to Mars in 2018. It seems like privately funded space exploration is catching on. My novel, Beyond Earth, explores this trend, and I think we'll be seeing many more such missions.

Whether Tito succeeds in his plan or not, it does bring up an important issue of interplanetary travel. According to DVice:
Tito... is going to try to swing two people around Mars without stopping and then bring them back to Earth on a mission lasting 501 days.
500 days in a 10 cubic-meter capsule for one or two days worth of sight-seeing? Whew! If they're not bored to death, they face the problem of cosmic rays and solar wind. Discovery News reports a study from the University of Rochester Medical Center that found:
--that exposure to radiation levels equivalent to a mission to Mars could produce cognitive problems and speed up changes in the brain that are associated with Alzheimer’s disease.
Wow! Go to Mars and come back a vegetable. There has to be a better way. Improved shielding technology would certainly help, but better still would be a faster journey. What I propose in Beyond Earth is 1G propulsion. For half the journey the ship accelerates out at 1 gravity, then turns around and deccelerates at 1 gravity for the other half. That would cut a 250-day outbound trip down to just a few days. It seems that manned interplanetary travel may depend on someone inventing an efficient 1G engine. Not only would it simulate the gravity of Earth that's so important to our physical health, but with high energy particles zipping through our brains, the less time in space the better. As Dorthy said after visiting Oz, "There's no place like home."

3 comments:

Boothby171 said...

Paul, those are serious questions that do not seem to be answered in the preliminary concept artwork for the mission. So far, the one illustration we have shows an inflatable Bigelow-Brand™ habitat bubble placed on the docking connector on a SpaceX Dragon capsule. And that's it.

Nothing about food stores, nothing about artificial gravity (which would have to be centripetally created), nothing about radiation protection. No place to store the Parcheesi pieces.

And Tito is hoping to bring 1960's sexual orientation biases with him, too:

"Anyway, according to Tito, this is because humanity's first flight to Mars should be represented by both genders, and because when you're that far from home, "you're going to need someone you can hug." " (Because, apparently, gays don't hug.)

But, liberal-minded sexual preference issues aside: in its current state, it looks like a high-school science project.

http://io9.com/5987372/everything-we-know-about-dennis-titos-2018-human-mission-to-mars

pstory said...

Thanks for your thoughts. There do seem to be a number of holes in his plan. I didn't give much thought to his choice of astronauts. Whoever he picks will likely be at each others' throats before the end of the mission, cramped in such a small space. It seems interplanetary travel awaits a faster mode of travel.

Boothby171 said...

A few years ago, I attended (and presented) at a conference dealin with manned exploration of space. I was there to present concepts on centripetally induced artificial gravity.

It was amazing how LITTLE had been done in that field. A graduate professor was there presenting on a tethered system for spinning up a module. After a year of work on that concept by him and at least 3 or 4 of his graduate students, that had a nice artists rendering about it, and had figured out what speed to spin it at for a given radius. They had worked out a few of the logistics, but it was obvious that they had not gone into any meaningful depth on it.

When I asked them about some practical issues (how does one keep the system from speeding up when they retract the tethers as part of their "normal operations") it was clear they hadn't through that at all.

In one night, I sat down and analyzed the stability (or, really, the lack thereof) in their approach. One person, overnight, in a hotel room with a laptop computer.

I hope I'm wrong, but I don't think these guys have thought this project through at all.