How brutal is the rocket equation?
Δv Δv, or delta-v, is what keeps orbital engineers up at night. Simply, delta-v is the change in velocity that is necessary for anything to happen in space. One of the great promises of a momentum-exchange tether is that the system can transfer tremendous amounts of delta-v to a payload without paying exponential costs to do so.1 However, we can’t evaluate these claims in a vacuum (ha). To really get a sense of the unreasonable effectiveness of tethers, let’s first look at the rocket equation more deeply. ...