shiri

@shortwavesurfer The propulsion is absolutely linear, the perk of an ion drive is that it's mostly electrical with minimal fuel consumption.

It's also something we're already using, the first one actually launched was in 1964, though for some reason we never stopped hyping it.

An ion engine would absolutely make the trip take *longer* as you'd have to wait for better transfer windows (9 months is the timeframe *after* we wait for a good transfer window), we'd have to wait even longer for one with an ion drive and it absolutely wouldn't be a shorter window.

@shortwavesurfer @InquisitiveApathy ion drives really don't solve any of these problems.

Orbital dynamics are *weird* and "more speed" isn't a solution. With orbital dynamics your relative position and speed are directly related, so moving faster basically means changing direction. Once you're in microgravity thrust power is more about how quickly you can steer and fuel quantity is how many maneuvers you can do. Ion drives can do a lot of maneuvers, but every maneuver is very slow (which also makes them more complicated because you need to account for the changes that happen over the course of the maneuver).

We don't travel to orbital bodies in a straight line because it goes beyond an absurd quantity of fuel to do so (ion drives don't even scratch the surface of the amount needed, let alone the complexity they add due to slow acceleration).

Right now we don't have much to improve the speed of getting places and not much on the horizon there either, so we're focusing on questions like how to survive getting there.

@saba @Recant We're definitely not going to have a moon colony in our lifetime, and a manned mars mission would only be a disaster.

The reason we haven't really gone back to the moon and don't have a colony there is because it's much more expensive to access and offers no real benefit over space stations. It's perk is low gravity instead of microgravity, but it trades off in massively increased fuel and time costs as well as the inability to "dodge" hazards. The moon has no special resources, no capacity for terraforming, and if we were wanting to build enclosed habitats we could do that more easily in a space station.

Mars is kinda worse because as far as I can tell we're finding problems faster than we're finding solutions. My favorite recent example of this is that we discovered anyone we sent would go blind before reaching the planet (microgravity destroys your vision over time, it took us forever to find out because the astronauts were hiding it so they wouldn't be disqualified from future flights).