Elon Musk
@elonmusk · Nov 24, 2015
It is, however, important to clear up the difference between "space" and "orbit", as described well by what-if.xkcd.com/58/
Elon Musk
@elonmusk
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.
12:30 PM · November 24, 2015 · 0 views
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