re: beautiful shot of the surface of mars from the curiosity rover

I’m not an expert by any stretch, but I think the prohibitive factor in sending humans to mars is radiation. We would need a means of shielding them from radiation once they leave earth’s magnetic field. The last I heard the Brits were working on a way to create a magnetic field around a spacecraft back in 2008 but I have no idea if anything ever came of it. If that issue isn’t solved then anyone on a 6-7 month voyage to Mars is taking a one way trip. Even if they make it, Mars has no atmosphere to protect from solar winds and no liquid outer core to generate a magnetic field to protect from radiation. So, again, it’s a one way trip with an agonizing end.