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3

There is another problem here. How to shield humans from the hard radiation (high energy protons and neutrons) from the Sun and Galactic cosmic ray sources, once outside the Earth's magnetosphere. Analysis of data from instruments on board the Mars Curiosity spacecraft and on the Rover itself, allowed Zeitlin et al. (2014) to compare the equivalent ...

7

Money certainly is one issue, but it is far from the only issue. It isn't even the biggest issue. Issue #1: Humans need air, water, and food. We can live without air for a few seconds, without water for a few hours, without food for a few days. And then we die. We need air, water, and food. And we don't know how to do that on Mars. There are conjectures ...

11

There are several issues with using ramjets on rockets: The startup problem. Ramjets rely on the supersonic velocity of the vehicle to create the compression needed for the combustion chamber to operate. So you'll need something (traditional motor stage, air breathing engine, etc) to get the craft moving to the point the ramjets can actually function. ...

0

The thrust for a rocket (can be demonstrated with global conservation of momentum on control volume set around the rocket) is, in general: $$\mathbb{T}=\dot{m}u_e + A_e\left( p_e - p_a \right)$$ where $\dot{m}$ is the mass flow rate $\left(\frac{M_p}{t_b} \right)$ (being $M_p$ the mass of propellant and $t_b$ the burning time) and $u_e$ the gases exit ...

0

To answer your question: yes, it's perfectly possible to achieve a sizable $\Delta V$ with an Electric Propulsion device as long as you take enough time and have enough propellant. EP is in general low thrust but high $I_{sp}$. I assume they have enough time and/or planned a low-thrust transfer rather than a more traditional method so we wont consider that. ...

0

Although a previous answer has been selected I think the asker needs a bit more info to understand what sort of questions you should be asking about a rocket. In particular, the Tsiolkovsky rocket equation is only ever used to compute a required mass ratio or delta-V. It's essentially a staging tool; given some total delta-V what are the number of burns and ...

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