Are probes like the soviet Luna 9 & 13 considered soft landers or hard
landers? Years ago, all the sources that I came across insisted that
soft landers had to use braking rockets to cut velocity, and that the
Lunas (and, by extention, probes that use airbags, like MER) were
survivable hard landers, ejected by a bus which then crashed onto the
surface. Is this distinction still used?