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Falcon Heavy to Loop Mars with Empty Nesters?

Dennis Tito wants to send an "older" middle-age couple around Mars in 2018 in a Falcon Heavy. http://www.bbc.co.uk/news/science-environment-21603490 Price tag $1.2 bn. Volunteers?

2018 really is near future.

Sure, we'll go - Provided he also funds my retirement if we make it. No doubt I'd lose my job having been gone for so long...

I was think... unlike many Mars mission plan I've seen so far, I think it would make most sense to not compromise too much on room and life support for the trip. This means I think it would make more sense to have a large space ship, complete with artificial gravity through rotation and even a green house where astronauts can garden and grow fresh lettuce and kale (a must for Musk the kale-eating overlord of Mars--just kidding). This large space ship would not descend to Mars or Earth, it would only orbit when waiting and otherwise would be a ferry between the two planets, so it would serve many, many times. I realize that lifting anything to space is expense per lbs or kg, for which I propose that a rocket could be suspended under a huge hydrogen balloon or blimp and a smaller one, perhaps half the volume, of oxygen. The oxygen balloon with have a very low weight because the oxygen is expanded and of similar density as air, and the hydrogen will actually lift the rocket to about 35 to 40 km, which will save fuel and weight (from extra fuel and fuel tank, and still extra fuel and fuel tank to lift the initial extra fuel and fuel tank, larger rocket for extra weight from extra fuel and fuel tank...) of up to 392,000 J per kg for that first leg of the trip, and not counting the compound effect noted above. The hydrogen balloon will still provide a bit of lift after 40km by diminishing the net weight of the rocket, but the hydrogen and oxygen will also be used as fuel to push the rocket out to space. So there is also large weight savings resulting from most of the fuel being expanded and therefore of near zero and negative weights, for oxygen and hydrogen, respectively. I know huge balloons could create a lot of wind resistance, but air is much thinner beyond 40km (I calculate less than 0.05% of sea level) and the rocket will start off slowly. Plus the balloons could be shaped so as to minimize wind resistance. By the time the rocket reaches 200 km, it will shed the balloons which will slowly and gently fall back to Earth because they are so light. They will circle the planet until the wind carries them to a location where they will be easy to retrieve to re-use for a future mission, thanks to a GPS and the ability remotely control altitude by burning some of the remaining hydrogen. Meanwhile, the rocket, by now traveling mostly in orbit, will continue its climb with fuel on board, perhaps even at some point switching to ion propulsion or less powerful but more efficient, therefore saving more weight.

Elon's comment that the lower atmosphere is "thick as soup" made me think of this balloon idea. Hopefully all this will help improve the 2-4% useful cargo margin he noted in regards to sending something to orbit.

Is it bad that I do not think it's very exciting to just fly by Mars?

Yes, I realize doing that still means that they do a lot of impressive engineering to be able to sustain two people in space that long at remote distances and yadda yadda, but really, I am just not inspired.

And it seems like an awfully huge effort with little payoff. I mean, yes, I totally understand that it would be a huge accomplishment, and that getting to the surface of Mars safely, and then back off of it and back home wouldbe way more complicated and so maybe we should take baby steps, but still, it seems like such a shame to go that close, yet be so far.

Also, man, for the two people, geez that would be boring. 500 days? I would pray for like an alien attack or something. Anything to make it interesting. I think after a week I would go crazy. I mean, maybe they could get the internet, but it would be super slow, and it would have to somehow compensate for the fact that a radio signal would take longer and longer the further they got away.

Haha, being on the ground and designing such a device that could let them use the internet would be interesting.

You would just cache a site. So you want to read the Times, you open the home page, then it says "caching...". You wait an hour or whatever, then you can navigate the site.

Your regular sites would be pre-cached.

There is no way to browse live once you are past a couple of million miles or so, which would be pretty darned soon. Latency quickly gets up to tens of seconds and then minutes.

The key might be to send two evenly matched chess or GO fanatics, who could happily spend 2 years playing each other.

Haha, funny comments, and that might be the solution, Brian.

olanmills
"[...] but still, it seems like such a shame to go that close, yet be so far."

Reminds me of that scene in Apollo 13 with sad Tom Hanks looking down as he flies by the moon without being able to land. I guess that would be called a teaser.

I think an internet connection could potentially be fast in terms of bandwidth, but of course where it would suffer is in unresponsiveness, kind of like watching a tv interview with a far away guest via satellite. I guess that rules out online computer games. If the travelers are avid gamers, they better bring games with lots of replay value, or like Brian said, they could simply bare it a play each other virtually to the death, or so it would seem.

I know Elon said he would like to retire on Mars as soon as possible, meaning when he will not be missed too much at SpaceX and Tesla and at home with his kids. I suspect that unless he goes senile, people will still want him around for longer than he would like, so I thought of a funny compromise image is that he could be CEO and chairman of his companies from Mars, beaming commands and orders to Earth, except with a 20 minute delay. Sure would feel weird.

Yeah, Elon sez he wants to die on Mars -- just not on impact. >;p

@Brian H - I love that quote. It makes me chuckle every time I hear it.

I don't think he said "as soon as possible". I think he has mentioned his fifties.

Given the current timeline, his late 50's (15 years from now), is possible. Kids will be grown by then. Tesla will be successful or dead, SpaceX successful, by definition, and Musk will still have another decade ahead of him to do real exploring, assuming he takes care of himself.

Assuming he's lucky. Life has taught me that, in contrast to the "take care of your health and you'll be fine" meme, genetics and other misunderstood probabilistic systems, which we can bundle under the label chance, has more to do with it than we tend to give it credit for. I'm not saying healthy living is wrong, but that we are fools if we think we can be mostly in control of our future through our past and present actions.

I also wonder how deeply Elon and other people have thought out the Mars colony idea. For one thing, we've all seen those artistic depictions of Mars colonies, but I'm pretty sure a Mars colony should be deep underground until the planet is terraformed. I'm considering writing a short paper about it, or maybe just a post.

Better idea is starting a Moon colony first. Lowers the transportation costs, and is easy to observe for flaws & errors that are bound to crop up.

Moon colony may not directly lower transportation costs, but I agree it would be awesome for:
-gaining valuable experience regarding building space colonies and the like, but with a wider margin for error because closer to home;
-Moon colony is bound to get done someday, so might as well do it first as a baby step;
-for space tourism because cheaper and much more accessible than Mars (4 days vs at least 6 months to get there), which could make the Moon colony more financially sustainable than Mars;
-for science in general;
-for absolutely awesome and unrivaled astronomy: operating nearly two weeks at a time, zero light or radio pollution (with Earth and sun hidden on the other side), insignificant atmospheric distortion, and the possibility for a telescope surface (up to the size of the face of the Moon) so large that it might allow astronomers to see incredibly further and clearer and discover that the universe is much larger than 16 or so billion light years in radius around us (in fact it's likely infinite);
-for harvesting of helium-3, an isotope believed to be the fuel needed for safe fusion power and which could be shipped to Earth economically viably I figure (probably the only commodity that ever could), and because helium-3 comes from the sun and falls onto the lunar surface, it is renewable;
-as a permanent base and a useful and accessible pit stop for whatever business will go on around the Earth neighbourhood.

Mars may always be ten years in the future, but the Moon is much more accessible, as we could probably start setting up a base there within one or two years of the Falcon Heavy rocket being ready for flight. A Moon base will give us the confidence go check out Mars next, as the Moon is as inhospitable as Mars. Elon is looking at Mars, but if he doesn't want the Moon, he should give it to me, make me governor, a kale-eating lunar governor. After all, who better to populate the Moon than lunatics?

Okay, I can no longer resist, I will tell you why I think a Mars or Moon colony should be deep underground. The obvious starter is protection from radiation and extreme temperatures. Also, consider atmospheric pressure:
http://en.wikipedia.org/wiki/Atmospheric_pressure

p = p0 (1 - [L * h]/T0)[g * M]/[R * L]

Or to keep it simple:
http://www.engineeringtoolbox.com/air-altitude-pressure-d_462.html
So we see that the peak of Mount Everest (above 8.8 km) has about 35% atmospheric pressure of sea level (atm), yet as we know that pressure is not lethal. Oxygen is low only because it is heavy and stays closer to sea level. Also, a hole 1500m deep here on Earth would have 120% atm. The values would be different on Mars or on the Moon, but the basic idea is the same, that deep underground on the Moon or at least on Mars, higher atmospheric pressures could be sustained naturally, even without compression. This could allow for life without pressure suits at the bottom. Oxygen need not be rare like at the top of Mount Everest, because if it is heaviest it would gather near the bottom and ten to stay in the colony. Only concern might be radon, but properly sealed walls could keep levels manageable and safe. So the idea is that a self-sustaining atmosphere is much better than pressure inside a capsule or pressure suit, for many practical reasons but also for safety. Maintaining a perfect seal could be challenging, especially at he surface where storms and radiation could degrade materials, let alone regular wear. Aside from all the practical considerations are the psychological, namely security. Being vulnerable to a sudden, lethal loss of pressure would be a huge stress. This stress might be manageable during an outing but it might make it difficult to sleep well. Likewise, could you find any volunteers to live kilometers under the sea (here on Earth) for two years or longer with no lifeline, so vulnerable to sudden death, or even worse, a slow drowning or "loss" of pressure? A colony that is not vulnerable to lethal loss of pressure because air naturally gathers there would feel much more comfortable and safe, and astronauts would greatly benefit at many levels.

Astronauts would regularly ride their Tesla rover to the surface to work and explore, and this is the only time they might need to wear their pressure suit (unless perhaps if the Tesla rover is pressurized). An underground Mars colony might not even need a door. Also, it could be dug out by robots prior to the arrival of the astronauts, which would also be an incredible exogeological experiment!

@TeslaRocks

Just fire the Tesla Laser from the Falcon, just like in Alien vs. Predator, you will have your tunnel in a second!

Brian H,
Funny quote..
However, the problem with those Chess players is that they would be back home before looking out the window. They won't be able to account for their trip...reminds me of the movie "Contact"


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