The latest, year-end Carnival of Tomorrow is up, and has a number of very interesting links (of which mine is undoubtedly the least interesting). Hard to believe that we're already almost four years into the new century, and millennium, and while we don't yet have flying cars, in many other ways, we're living in the science-fiction future of our childhoods, at least for those baby boomers among us.

He has a link in there to an article from September about the impossibility of SSTO. While the article made some interesting points, one thing confused me - he said that a LH/LOX rocket needed a propellant mass fraction of 92%. Isn't that high? My calculations show the 92% at 450 Isp would give you 11 km/s delta-v - I thought that orbit was 9 km/s, including losses. Am I really that far off?

Probably not. Jeffrey Bell is usually full of crap. That was a seriously flawed piece, as most (all?) of his are.

"... while we don't yet have flying cars, in many other ways, we're living in the science-fiction future of our childhoods, at least for those baby boomers among us"

We also are not living in space which was supposed to be a part of 'Century 21 - the World of Tomorrow. (I was so young when I went to that world's fair that I believed everything would be exactly the way it was displayed.)

We do have a bit of technology that was not even dreamed of yet back then so I guess it evens out.