Chemical propulsion is obsolete to go anywhere other than the moon. Three days - that's acceptable. But for Mars, we need propulsion technologies to get us there in, say, 60 days - then spend whatever length of time we want… — Anonymous Copy Share Image
For decades, people have known the chemical-propulsion approach to space travel is really not going to get us that far. Chemical propulsion is essentially like the horse-and-cart approach to the exploration of the American West, instead of the steamboat or… — Franklin Chang Diaz Copy Share Image
