> >even if it is expendable, we can manufacture the things by
> >the zillions and still get payload to orbit for less than 5k$/kg. spike
> Randall Randall wrote:
> Notice, as well, that the target price for the roton is 2.2k$/kg,
> less than half of the price you mention. Cost is the major factor
> for many industries...
randall, i saw on their site the target price and i hope they can make something like that happen, but... i fear the roton folks are taking a promising technology and overpromising it. {8-[ i see the scientific american article has all the elements: true single stage to orbit with reentry system and full reusability. by promising all that, they cause investors to be disappointed if it falls short, even tho it is quite an impressive achievement just to make true single stage to orbit.
for those who are interested in our future in space, please check out that article and comment on which system looks the most promising. that outfit in kirkland washington with the k1 two stage to orbit and full reusability looks like the best bet to me.
the article mentions using bucky tubes to make a geosynchronous cable to the deck, but no mention is made of the biggest show stopper with that scheme, even if we manage the materials problem: every satellite crosses the equatorial plane twice each orbit. several years ago i calculated the probability of a collision at 45% per year. {8-[ i suspect that estimate is low. such a thing might be possible on mars however, as it turns a bit faster and has less mass than the earth, and fewer artificial satellites. spike