[wolf550e]

As Elon Musk wrote [1]:

  It is, however, important to clear up the difference between "space" and "orbit", as described well by https://what-if.xkcd.com/58/

  Getting to space needs ~Mach 3, but GTO orbit requires ~Mach 30. The energy needed is the square, i.e. 9 units for space and 900 for orbit.

1 - https://twitter.com/elonmusk/status/669129655597731841

[andygates]

Of course, going slower means less acceleration, which means less high-G discomfort for paying passengers. A vertical hop makes perfect sense for meerkat-mission tourism.