” In the long run, it’s impossible to make progress without sometimes having setbacks, although people who get lucky on their first attempt sometimes forget this. “
” The communications delays between Earth and Mars can be half an hour or more, so the people on the ground can’t participate minute by minute in Mars surface activities. “
” NASA has never had a problem finding capable people to be astronauts. NASA’s problem was, and still is, finding ways to cut the list of capable applicants down to a manageable length. “
” Sometimes people wonder why aeroplanes are so cheap and rockets are so expensive. Even the most superficial comparison shows one obvious difference: aeroplane engines use outside air to burn their fuel, while rockets have to carry their own oxidisers along. “
All 4 Henry Spencer Quotes about People in picture


Topics: People quotes