# What type of propulsion system will get us to mars? **URL:** \ **Category:** Factual Questions\ **Created:** [July 28, 2011, 6:11am UTC](https://boards.straightdope.com/t/what-type-of-propulsion-system-will-get-us-to-mars/590595 "2011-07-28T06:11:56Z")\ **Posts on this page:** 4\ **Page:** 4
**Author:** ![Trinopus](https://avatars.discourse-cdn.com/v4/letter/t/2bfe46/32.png) [@Trinopus](https://boards.straightdope.com/u/Trinopus)\ **Post date:** [July 29, 2011, 9:24pm UTC](https://boards.straightdope.com/t/what-type-of-propulsion-system-will-get-us-to-mars/590595/61 "2011-07-29T21:24:29Z")
> [@outlierrn](#): > > Ahh, but there is > > [http://www.youtube.com/watch?v=1uPznTbus3g](http://www.youtube.com/watch?v=1uPznTbus3g) Mountain unicyling… My entire brain hurts… Thank you for making my life that much more surreal! Trinopus ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [July 29, 2011, 10:34pm UTC](https://boards.straightdope.com/t/what-type-of-propulsion-system-will-get-us-to-mars/590595/62 "2011-07-29T22:34:20Z")
> [@davidm](#): > > \ For a completely unworkable ridiculous tongue in cheek suggestion just to get us thinking in unorthodox ways: how about sending an automated ship which lays a cable between here and Mars, anchors it on Mars, then reels it in after we attach the manned ship to the Earth end. 😛 Let’s go for it, but you hold the line here, until the other end reaches mars. Now… who’s got 300 million miles of monofilament? > [@Trinopus](#): > > Mountain unicyling… My entire brain hurts… Thank you for making my life that much more surreal! > > Trinopus Wait a second. No pink tutu? Without the tutu, and an undersized parasol, that sport just looks silly. ---
**Author:** ![Icerigger](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/icerigger/32/432_2.png) [@Icerigger](https://boards.straightdope.com/u/Icerigger)\ **Post date:** [July 29, 2011, 10:47pm UTC](https://boards.straightdope.com/t/what-type-of-propulsion-system-will-get-us-to-mars/590595/63 "2011-07-29T22:47:52Z")
Sadly we had the power plant, built, tested and running but gave up on it. > **[NERVA](https://en.wikipedia.org/wiki/NERVA)** > > The Nuclear Engine for Rocket Vehicle Application (NERVA) was a nuclear thermal rocket engine development program that ran for roughly two decades. Its principal objective was to "establish a technology base for nuclear rocket engine systems to be utilized in the design and development of propulsion systems for space mission application". NERVA was a joint effort of the Atomic Energy Commission (AEC) and the National Aeronautics and Space Administration (NASA), and was managed by the Space Nuc... ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [July 29, 2011, 10:57pm UTC](https://boards.straightdope.com/t/what-type-of-propulsion-system-will-get-us-to-mars/590595/64 "2011-07-29T22:57:11Z")
You could build a solar sail ship, but that’s a solution to the wrong problem. Ultimately, the reason why a conventional rocket wouldn’t be practical for a trip to Mars is that it would take too damn long. A Saturn V could do it, if it only had to send an Apollo-sized capsule. But now put a couple years worth of food and oxygen and radiation shielding and health equipment and entertainment in that capsule, and you’re way over the weight limit. A solar sail would require no more fuel than it takes to get to low Earth orbit, but it would take far, far longer to get to Mars. The cable idea has more promise. No, really. You obviously can’t run a cable the whole distance, but you _can_ run a cable from the surface of the Earth up past geosynchronous orbit, and another one on Mars. You can get huge tonnages into orbit that way, arbitrarily cheaply. And if you go further out than geosynch on the cable before letting go, you can get a pretty hefty launch speed. The catch is that the cable needs to be strong enough and light enough to be able to support its own weight. Steel won’t do it, spider silk won’t do it. Carbon nanofiber _would_ do it, but we don’t yet know how to make that in significant quantities. Of course, even aside from space elevators, strong, lightweight materials are always in high demand, so we’re working on ways to make it practically. [Previous page](https://boards.straightdope.com/t/what-type-of-propulsion-system-will-get-us-to-mars/590595.md?page=3)