Henry Spencer

Foul-ups in testing are not uncommon, especially when the test setup is being tried for the first time.

The demise of Constellation is not the death of a dream. It's just the end of an illusion.

Sure, there were hopes that Constellation's systems could later be adapted to support more ambitious goals. But Apollo had those hopes, too. It didn't work in 1970, and it wasn't going to work in 2020.

The Apollo programme of the 1960s had some weight problems, too; in particular, the lunar lander needed some fairly drastic weight-reduction work.

Progress requires setbacks; the only sure way to avoid failure is not to try.

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.