ME: <<Why is a 4.0 Km/s deltaV to EML so great when it is 3.2 to reach the Moon and 2.7 to land (which I think you need even coming from EML) and 3.6 top reach Mars and 1.0 to land[?]>>

Honestly? When you're going one way it's not that great. But when you're at the crossroads of many different functions it's both the going and the coming that are important.

Mars is a destination. EML-1 is a transit node.

It's kind of like how we don't take off from the middle of Dallas to land in the middle of NYC. We take the appropriate form of transportation (car/bus/train/helicopter) to DFW airport, board a plane there that takes us to JFK, where we take the appropriate form of transport (taxi/car/bus/train) into Manhattan. Possibly through a hub city.

Or how cargo takes a truck to the port, where it takes a boat or plane across the ocean to another port, where it goes by truck or rail/truck to its destination.

You transport to the ISS by STS/Soyouz/Shenzou/Pressurized ATV, take an OMV out to EML-1, where you transfer to your final destination, be it EML-1 itself, the Moon, Mars, or points beyond.

I'm indifferent to the design of the Earth to orbit vehicle versus the OMV. I have no preference as whether they should be one in the same for everything or significantly different. However, I do have a strong preference in achieving a commonality in design across the board.

I firmly believe that we can design a vehicle that will serve well to get people to orbit, and with a bit of modification can serve extremely well as an OMV, and with slightly different configuration can serve as a planetary lander for use on the Moon or Mars. Perhaps its a capsule that you bolt something onto once it's in orbit (heatshield for return, cargo truss/propulsion unit for orbit). I don't care. Just give me a design that gets X number of people to and from orbit, the same number of people to EML-1, and from there to the Moon's surface, or to the Martian surface, or to an asteroid, or wherever, and where you don't need completely different designs for each step. Cripes, you'll never get scale efficiencies in production that way.

The point is that for a permanent presence in space you need multiple levels of redundancy and efficiency. Sometimes you give up a little efficiency here to get a lot more value there.

ME:<<The landing delta V for Phoebos and Demos is 1.9 km/s so I would expect similar values for most asteroids since there is a big size difference in those two.

Again I don't know how you calculate those values.>>

I quoted two sources. Let me repeat them here so you don't have to go back to the other post:

Human SMAD
Lunar Base Handbook

The tables therein have a certain "fudge factor" to them because you can never be quite sure of all of the assumptions that went into the computations (Moon's here, Mars is there, six months past Aries, etc., etc.). However, my calculations have typically been pretty close to those numbers, so I feel comfortable using them from the book (with my own fudge factor thrown in to allow for margin).

And by the way, I do recognize that the inclination used in the LEO calculations in Human SMAD are for a different space station than the ISS, but as I noted, your inclination from LEO doesn't really matter too much when you're going to EML-1. No plane change dV penalty.

If you want to know my sources for orbital mechanics, here we go (sigh):

Bate et al - Fundamentals of Astrodynamics
Berman - Astronautics: fundamentals of dynamical astronomy and space flight (one of my favorites)
Bond & Allman - Modern Astrodynamics: Fundamentals and Perturbation Methods
Carrou (ed.) - Techniques Spatiales: Mecanique spatiale (Good stuff, helps to give a feel for why the French gave up on the Hermes)
Murray & Dermott - Solar System Dynamics (nice for ephemeris stuff)
Roy - Orbital Motion
Szebehely - Adventures in Celestial Mechanics: A First Course in the Theory of Orbits
Thomson - Introduction to Space Dynamics
Vallado - Fundamentals of Astrodynamics and Applications (Great book! Definitely in my Top 10 space references)
Wiesel - Spaceflight Dynamics

and various papers as well.

I have to assume that at least a few of these authors are competent and well-respected in their field.

ME:<<You spend more energy to reach an orbital point, still have to pay some deltaV to reach another point, and still have to pay the deltaV to land.

This sounds like the silliest most idiotic waste of resources I've ever heard of. To want to go there because its [sic] easy to go somewhere else from there without bothering to note that you just made the whole trip harder to obtain no resources is just stupid.

EML only makes sense to me when that is the final destination because of orbital stability/positioning requirements.>>

That's fine. I understand that you only see sense in it when that is the final destination because of orbital stability/positioning requirements. To what purpose, then, would you put the EML-1 point?

I have proposed:
-Early emplacement for asteroid detection scopes
-Other astronomical instrumentation
-Probably some military Earth-watching stuff that I don't care to speculate on

All of which can be refueled/serviced/upgraded by human missions. While there, they can also:

-Refuel/service/upgrade the other Libration scopes that have come wandering back in on low energy trajectories, minimizing their fuel requirements and allowing them to serve on station longer. (What's our replacement for SOHO, anyway?)

-At some point, probably not too far off, things will get to the point where there's enough going on out there that it makes sense to put people out there full time. At that point your capabilities expand to include:

-teleoperation of Lunar robotic vehicles without the time delay
-post-launch inspection station for outward bound craft (a huge! benefit)
-Garage for dead GEO sats (round-trip dV (<3 km/s) is cheaper even than just getting from ISS to GEO (>4 km/s))
-Test bed for solar power satellites
-Beamed power source for Lunar operations
-Serve as a fuel depot from Lunar oxygen and hydrogen production
-Logistics center for construction of GEO SPSs and Comm sats
-etc., etc.

Everything I've suggested has direct or near-direct application to Earth benefits, from a scientific, engineering or commercial viewpoint.

Now my question is: Where do those functions fit into the Mars First scheme of things?

Does the Mars infrastructure propose to operate asteroid detection systems?
Not just NO, but an Emphatic NO from everyone here.

Does the Mars infrastructure propose other astronomical applications?
I speculate No.

Will the Mars project allow for military application?
Can I hear an ain't-no-friggin-way-over-my-dead-body NO!

Will the Mars infrastructure allow for telerobtic operation of Lunar oh never mind.

Will the Mars project inspect/service outbound craft (i.e. a Gallileo follow-up kinda thing)?
I don't think so.

Will the Mars infrastructure allow for a GEO cleanup?

Does the Mars infrastructure propose to serve as a testbed for solar power satellites for a power hungry Earth?
(Cue sound of crickets chirping in the background)

Will the Mars project beam power to the Moon for ah fuhggedaboutit.

Will Mars serve as a fuel depot for cislunar operations?
Didn't think so.

ME:<<The focus on the delta V issue is to kill the false arguement [sic] that the Moon is a key path to Mars. It's not the only issue, but is the key false issue that keeps raising its ugly head. Far to [sic] many people buy the arguement [sic] that we have to go back to the Moon to go to Mars rather than focusing on which is of more inate [sic] value as a target.>>

I've never said that the Moon is a key path to Mars. Nor that Mars is a key path to the Moon. I've maintained that EML-1 can serve as a key stepping stone to both, since it's on the way to both, as well as to a lot of other places.

As far as the "inate value" goes, that's pretty much a function of the priorities and agendas.

ME:<<As far as Mars NEO detection goes you keep avoiding admitting you grossly misrepresented the context of the Mars/NEO debate. You can't build consensus by paying so little attention to others [sic] views that you totally misrepresent their arguements [sic]. You especially can't do it if the misrepresentation is intentional which I assume it wasn't, although continued evasion of admitting the error makes that appear more likely.>>

No, No, a thousand times no! I have never said that going to Mars is a rationale for NEO detection. Never! Any reference in that regard was to point out the gross disparity in the priorities and agendas of one versus the other. And if I remember correctly I discounted that idea in the same post in which it was brought up.

Let me say it again to be clear:

YOU DO NOT GO TO MARS TO LOOK FOR NEOS: YOU DO NOT GO TO THE MOON TO LOOK FOR LIFE

I never said that Mars is a viable NEO detection spot (other than MSL-2, but that's via EML-1, not Mars). I am in full agreement with you that it is an absolutely absurd proposition. We have no disagreement in this regard. Can I assume that we will no longer waste bandwidth on this? Thank you.

Conclusion:
So yes. Getting to EML-1 isn't cheap. But as I have consistently stated the dV IS NOT the only factor, and there are a LOT of other factors to look at.

Purely speculation, because no one really knows, but I'd put money on a Mars First! space infrastructure ending up being More expensive, dV-wise , over the medium- to longer-term once space operations really get underway.

Unless of course, there's really no point in going to space other than to go to Mars, and by the way, LEO is a cheaper dV destination than any of the above.

Cheers,
Ken

P.S. Here's an image for you.

(Cue TV reporter)
Today marks the launch of humanity's first mission to our closest planetary neighbour. As you can see behind me, there are thousands of people gathered together here to share in the launch, something that's happening in cities and towns across half the globe.

The Mars-bound craft, Ares-1, is even now moving away from the EML-1 station after having been thoroughly checked and double-checked to ensure that all systems will function perfectly (cue to corner window of Emilycam showing the craft moving away). Once it moves a safe distance away it will ignite its main engines for the long journey to Mars.

Wait, wait, yes, something's happening. Arms are starting to point to the sky. Can you get that? Yes, very faintly, like a diamond in the center of the Moon you can just see a pinpoint of light from the ionized particles being thrown from the new High Performance Ion Thrusters. It seems only fitting that the Moon should serve as the backdrop for our next step out into the Cosmos.

It's starting to track towards the edge of the Moon. People around me are cheering and shouting words of encouragement to the brave departing spacefarers, something that hundreds of millions of people on this side of the world are doing even as I speak. There's going to be a lot of celebrating going on tonight on this most important of days in human history and achievement.

Back to you in the studio.

(static)

Now that's poetic.

K