Not me this time, but it looks like an interesting lineup this week:

1.Monday, Feb. 26, 2007, 7-8:30 PM Pacific: Dr. Lee Valentine returns to discuss the upcoming Planetary Space Conference, commercial space investments and much more.

2. Tuesday, Feb. 27, 2007, 7-8:30 PM Pacific. Stephen Metschan, President & CEO of TeamVision Corporation comes on board to discuss the comprehensive TeamVision plan for returning to the Moon and going to Mars.

3. Wednesday, Feb. 28, 9:30-11AM Pacific: Dallas Bienhoff, an engineer with Boeing, joins us to discuss on orbit fuel depots and much more.

I worked with Dallas on the CE&R studies a couple years ago, in which we fleshed out a lot of the features and advantages of propellant depots, in LEO and elsewhere. NASA continues to prefer a return to Apollo.

fuel depots make a lot more sense for a moon mission
then "Apollo on Steroids."

When I was working out my military basic prep, I was always
told that steroids shrink your testicles and make you crazy.

Which might explain mike puckett.

Why is an orbital fuel depot useful, Rand? I thought nearly all your fuel went into getting from ground to LEO, and that what it took to get from LEO to the Moon (say), was a fairly trivial addition thereto.

Rand, are there any public documents about the Boeing depot studies? It would be very fascinating to read them.
Lockheed Martin sure has many about Atlas and Centaur solutions for the future. (hint, hint)

Carl,
It turns out that about 50-90% of the mass in LEO of anything going to Geostationary Orbit, L1, Lunar Orbit, Mars, or beyond, is going to be propellant. Yeah, you burn an even bigger amount of propellant getting up to LEO in the first place, but you're still mostly propellant in LEO. Which means that if you can launch your satellites or transfer vehicles, or what-have-you empty, and then tank them up in LEO, you can get away with a much smaller launcher flying at much higher flight rates. No need for uber-heavy lift, and only little need in the near future for complex orbital assembly (orbital assembly is useful, and putting off learning how to do orbital assembly intelligently is a bad move, but for most nearterm projects it just isn't much needed if you have a propellant depot).

~Jon

For MZ, and anyone else, my STAIF paper and presentation are available for the asking. Only the abstract made it into the STAIF publications as the paper was a late addition thanks to John Mankins and Bob Wegeng.

Some other reasons for a LEO depot for the NASA architecture, in addition to Jon Goff's comments, include: the Earth Departure Stage uses ~half its propellant getting to LEO and the other half for the translunar burn so the Ares V could be downsized to do the same job or more mass can be landed on the Moon if the EDS is full in LEO; if Loral's Aquarius, Space X's Falcon, or RPK's K-1 are successful, their projected prices to LEO are less than the Griffin-stated LEO propellant value to NASA so a commercial depot may be able to reduce the cost of getting mass, especially surface payload mass, to the lunar surface; a depot can drive up the launch rate of any system, which is the single largest contributor to the cost of space access; having a LEO depot removes propellant boil-off and long-term cryo storage capability as design considerations for the EDS and Descent Stage and places that burden on the depot, a stationary long-lived infrastructure item. There are probably others as well, but you get the picture.

NASA's ESAS requirements aren't at any stage driven by cost, they're driven by employment. If they were driven by cost they'd most certainly be using the Atlas V to launch the mission hardware.

There is exactly zero chance that NASA will be buying LOX in orbit.