Re:Why We’ll Have Evidence of Aliens–If They Exist–By 2035
by tzs on Friday October 06, 2017 @03:19AM
(#15414990)
I wonder if there are intelligent species that are incapable of developing spaceflight due to environmental reasons. For example, an intelligent water-breathing species on a planet that is quite a bit more massive than Earth.
A ship filled with water has a lot more mass than a ship filled with air. That extra mass compared to what we face, combined with starting from a high gravity world, would mean they would need significantly better propulsion systems than we need to get to orbit.
Could this mean that chemical based rockets would not be sufficient for them to do manned spaceflight? If so, they may never establish a manned orbital presence, and a manned orbital presence may be necessary as a stepping stone to interstellar travel.
A ship filled with water has a lot more mass than a ship filled with air. That extra mass compared to what we face, combined with starting from a high gravity world, would mean they would need significantly better propulsion systems than we need to get to orbit.
Could this mean that chemical based rockets would not be sufficient for them to do manned spaceflight? If so, they may never establish a manned orbital presence, and a manned orbital presence may be necessary as a stepping stone to interstellar travel.