Titan's Resources and Their Utilization | Hacker News Reader

Titan's Resources and Their Utilization

arxiv.org

26 pointsbookofjoe14 comments

Illustrative video:

>On Jan. 14, 2005, ESA's Huygens probe made its descent to the surface of Saturn's hazy moon, Titan. Carried to Saturn by NASA's Cassini spacecraft, Huygens made the most distant landing ever on another world, and the only landing on a body in the outer solar system. This video uses actual images taken by the probe during its two-and-a-half hour fall under its parachutes.

https://www.youtube.com/watch?v=msiLWxDayuA

Thank you SO much for this! I just watched it and my jaw dropped to the floor. What an accomplishment. I thought about a hundred years or so from now when there will be a base on Titan and explorers on and above the surface will happen on this probe, hopefully right where it landed in 2005. Worth building an exhibit/museum for visitors on the site, it seems to me....

Huygens was an amazing project. It also sticks in my head as a really instructive example of "bug in production code" - the Huygens probe was transmitting on two channels to the Cassini orbiter during its descent. Due to a mistake in the Cassini software, one of the receivers never got switched on. 900 million miles from Earth and during a one-off unprecedented probe landing on an outer solar system body. Half the images and some wind speed data lost.

I don't know if the exact details of the bug ever got published but it would be interesting to know how it slipped through testing.

JPL tests in production!

I wonder if you could design a plastics production plant, injection molding system, propellant plant and an extremely large potato canon in order to launch large canisters of hydrocarbons and oxygen on a slow return trip.

Slow return trip to where? There’s plenty of both on Earth, so no point. But it may be easier to send bulk resources from Titan to the Moon or HEO than from Earth. I think the delta-V is lower, anyway.

The inner solar system was what I was thinking, returning to Earth like you said is a bit pointless but even a slow trajectory with a constant supply would be useful to have fuel and feedstock already in orbit near Mars and Earth.

The Hohmann transfer time between Saturn and Mars/Earth is around 16 years. So, all the ships used for such a supply mission would reach their destination at least 32 years after they’ve been built, assuming we build them on Earth.

That's not really a problem if the supply is continuous. Think of the last time you drank a 12-year scotch, that distillery had to be set up and start producing at least 12 years ago for them to label the product that way but they've continued production constantly since then which ensures there is a steady supply to be delivered to stores.

Spirits are not capital intensive. Building a rocket is very capital intensive. You'd like to be able to reuse it. But if one single mission takes 30 years, then you can reuse this rocket once, at most twice. Let's say you reuse it twice, you amortize the capital cost over a period of 90 years. Now, let's say someone builds the exact same rockets, but they do missions between the asteroid belt and Mars. Each trip takes about 2 years. Everything you can source on Titan, you can find an asteroid to source it from. By the time you reuse a Titan-bound rocket once, you reuse an asteroid-bound rocket many times.

I'm not sure what you're talking about, my initial comment was a (sort of silly) idea about building a mass driver on Titan that uses native materials to launch payloads on an inward bound trajectory, not to ferry them back and forth with a rocket.

That's an interesting idea, but I don't think you can use a mass driver to shoot something from an higher orbit to a lower orbit.

True, it would need to accelerate somehow. Maybe there could be some kind of on board propulsion that would be enough once it's in space. Solid rocket motors could be fabricated as part of the process but the timing and control systems would pose a problem. Maybe something clever could be done mechanically that leveraged temperature or pressure changes.

Sure you can — you just fire it went pointing ‘backwards’. But either way, you still need a burn to circularise the orbit when you get there.

Reply on news.ycombinator.com