New answers tagged

4

Of course, but relative to what? For example, consider the rotation of the Earth. At the equator, the ground (with you on it) is moving at 1670 km/hr. You could travel very fast if you "just stopped". But how would you stop? You'd have to somehow start moving 1670 km/hr relative to the earth. That's very very fast. In this case "stopping" ...


0

Going to Mars is going to need a lot of cargo. Elon's plan is to send 2 starships of cargo to Mars before any crewed mission. (He's been uncharacteristically consistent on this, given how much he usually changes his mind.) Even for Elon (let alone NASA) this is a minimum safety requirement. I'd want to see the propellant factory up and running and at least ...


0

The ratio of total mass to propellant mass becomes better the larger the fuel tank is, therefore a bigger tank provides more delta-v. (I.e. the tank has less dry mass per amount of propellant it can hold the bigger it is). The reason for this is that the volume of a cylinder or sphere scales roughly with the square of its radius, while its surface only ...


10

Why not both? You've correctly identified that there are two economies of scale - the first being in production (the more we produce, the cheaper it gets) and the second being payload per flight (the more we carry, the cheaper it is). The problem is you think starship is attempting to do the second, at the cost of the first. This is not correct. Starship ...


8

When sending something to Mars, it seems space agencies wait until Mars is about to reach the closest distance to Earth. from: https://en.wikipedia.org/wiki/Launch_window Sending one mission instead of dozens would open up additional launch sites as well since the preferred launch window is limited.


34

A lot of launch costs are independent of rocket size. It's no cheaper to clear the flight path for a smaller rocket, for example. It also takes a lot longer to do 10 launches instead of one large launch, and spaceflight is full of cases where you have limited launch opportunities. A larger vehicle will have higher throughput and lower costs per kg. Smaller ...


Top 50 recent answers are included