Economic expansion and liberty, by Mars Maniac in Chief Ken MMinC., and occasional brilliance and humor by CJ.
Friday, January 30, 2015
Thursday, January 29, 2015
Show Low today
Will probably catch a movie when I visit my bank in Show Low today. Two front tires and an oil change are all I have left to prepare my truck for my pending trip. Also will extend my insurance for another six months which expires at the end of march.
Four weeks of abject poverty, then I hit the road.
I have a lot of places I hope to visit. A lot of people to see.
Mainly I will try to get my head focused. Life should not be so consistently miserable although I see no potential relief on the health front. Being alone is the worst of it. Not being around people will strangely provide some relief from that constant pressure.
They say misery loves company. Company however, is disinclined to support the miserable. Understandably so. I have to go stick my head in the toilet now for the second time this night. Doctors are completely worthless.
After this trip I expect to come to terms with my situation. I will need to arrange some personal space. I have none at this time. Otherwise, there is no point in coming 'home.' Aren't I the cheery fellow?
Update: Both theaters in Show Low had American Sniper, didn't go to either. Got tires and oil change, so my truck is ready. Will get insurance next month so I have something left for this month. Now I wait.
Four weeks of abject poverty, then I hit the road.
I have a lot of places I hope to visit. A lot of people to see.
Mainly I will try to get my head focused. Life should not be so consistently miserable although I see no potential relief on the health front. Being alone is the worst of it. Not being around people will strangely provide some relief from that constant pressure.
They say misery loves company. Company however, is disinclined to support the miserable. Understandably so. I have to go stick my head in the toilet now for the second time this night. Doctors are completely worthless.
After this trip I expect to come to terms with my situation. I will need to arrange some personal space. I have none at this time. Otherwise, there is no point in coming 'home.' Aren't I the cheery fellow?
Update: Both theaters in Show Low had American Sniper, didn't go to either. Got tires and oil change, so my truck is ready. Will get insurance next month so I have something left for this month. Now I wait.
Wednesday, January 28, 2015
This author will never understand WHY?
A great article on Mars One by an author that will never understand why? Josh has the right stuff.
Tuesday, January 27, 2015
The ultimate controller...
...is getting closer. Combine this with a 3d output and you'd never need to leave your head. Beware of brainhackers!
Sunday, January 25, 2015
Red lander
In CJ's last post (his best yet) he mentions 10 passenger mars landers. Does this fit within the parameters of the previous 4 passenger, 2500 kg payload landers? Easily.
Volume is no issue. If you've seen photos of existing Dragons it's obvious there is room for 10 for a short duration landing. Assuming each suited crew is 200 kg that leaves 500 kg of consumables. 50 kg each or about a week of supplies... enough to get them to a prepared surface habitat. They aren't going to stay in the lander any longer than they have to.
At $150m per lander which can bring more than 500 kg to the orbiting ship if needed that gives us a per crew cost from orbit to surface of $15m each. Add another $15m from earth to LEO and we only need an estimate for orbit to orbit (will update in a bit) to get total cost per crew.
$50m total sounds about right. About a third my former estimate.
[Update: 185 ton of fuel and supplies requires 3 FH or one BFR so let's call that $300m or $3m per crew. I'm going to stick with my $50m total per crew estimate.]
Volume is no issue. If you've seen photos of existing Dragons it's obvious there is room for 10 for a short duration landing. Assuming each suited crew is 200 kg that leaves 500 kg of consumables. 50 kg each or about a week of supplies... enough to get them to a prepared surface habitat. They aren't going to stay in the lander any longer than they have to.
At $150m per lander which can bring more than 500 kg to the orbiting ship if needed that gives us a per crew cost from orbit to surface of $15m each. Add another $15m from earth to LEO and we only need an estimate for orbit to orbit (will update in a bit) to get total cost per crew.
$50m total sounds about right. About a third my former estimate.
[Update: 185 ton of fuel and supplies requires 3 FH or one BFR so let's call that $300m or $3m per crew. I'm going to stick with my $50m total per crew estimate.]
Saturday, January 24, 2015
BFR and MCT: Some thoughts on what they will look like, and be able to do.
BFR and MCT; some thoughts on what they may look like, and
what they will be able to do.
There’s been much speculation on what SpaceX’s “BFR” (a non
official designation meaning “big freaking rocket”, or other variants of the
middle word). What’s known is it will use Raptor methlox staged combustion
engines, and the design intent it to make it totally reusable. The specs on
Raptor keep changing, and I highly doubt SpaceX will settle on a BFR design
until the engine design is finalized (doing otherwise would be insane).
So, let’s work with what we’ve got; BFR will be big, and be
reusable, and use Methlox. It will have a low cost per pound to orbit (or it
won’t be built). It will also carry MCT (Mars Colonial Transport) to orbit on
some missions.
Now lets get into the specs, and the first spec to look at
is, of course, $$$. Developing BRF and Raptor will cost one heck of a lot. It’s
been theorized that SpaceX will pay this out of pocket and use BFR for nothing
but its own Mars launches. I consider this preposterous; we’re talking
billions, and there’s no reason to do it that way, so why not save that money
for other purposes? SpaceX has always optimized for cost.
BFR is planned to be a very large, fully reusable, system,
and thus should have a very low cost per pound to LEO. I’ve long argued that
they’ll offset R&D and construction costs the way they always have; by
selling launches. Why wouldn’t they? The counter argument has always been that
there’s no call for that much capacity, but SpaceX’s recent announcement of a
4025 satellite constellation, plus other companies being interested in such
large constellations, blows that argument out of the water; there may well be,
and soon, plenty of demand for a large low-cost-per-pound launcher. Selling
such launches (or using them internally to launch revenue-generating sats) is
IMHO how SpaceX will offset the R&D and construction costs of BFR. One
result of this will be a far lower per-Mars-mission launch cost – because the
infrastructure will already exist, and will have been paid for. (A current
example of this dynamic; SpaceX is using paid-for expendable launches to
develop its reusable F9R).
Now, this gets us to MCT, the Mars vehicle itself. SpaceX
has released little but the name and payload capacity, so there has been much
speculation. Much of the speculation claims that MCT will be able to go, on its
own power, from LEO to a landing on the surface of Mars, and then (after
tanking up ISRU) return from the Mars surface to Earth’s surface. The inherent
problem with this concept is the rocket equation and the fuel fraction
required. Building a craft able to land on Mars, as well as fly a reentry and
land on Earth, requires one heck of a lot of dedicated mass (heatsheild, airo
surfaces, landing engines for Mars, and above all structural strength). Let’s
use a Boeing 747 airliner as an example; its cargo capacity (cargo version)
maxes at 123 tons, within the ballpark for MCT’s claimed 100 tons payload
capacity to Mars. The 747, bare bones empty (without fuel or cargo) masses 128
tons. So, one ton of cargo for roughly 1 ton of aircraft. Not too bad… but if
you start adding things like heat shielding and life support, plus the heavier
pressurized compartment needed for space, you’re increasing it by a lot.
For comparison, the Space Shuttle orbiter had a dry mass of
110 tons, and could loft 25 tons, a ratio of greater than 4 to 1 (and the
Shuttle didn’t carry its primary fuel internally, so didn’t have the mass of
the external fuel tank counted). So, let’s say that, via some magical
engineering a liberal use of unobtainium as a structural element, you can get a
better mass/payload ratio than Shuttle (with its tiny pressurized volume and no
significant internal tankage) when scaled up to the size of a 747’s internal
volume and cargo capacity. Let’s call it a 4-1 ratio.
Where does that leave us with a postulated surface-surface
MCT? It has to be able to land on Earth and on Mars, as well as have all the
life support and other equipment needed for long-duration deep-space missions.
Let’s be optimistic and assume the 4-1 ratio above, and we get 400 tons. But,
we’re forgetting something; the fuel tanks. Shuttle didn’t include them in the
airframe (except the small hypergolic supply) but airliners do (and doing so
adds a lot of mass). The heat shielding shielding, and structure, has to
protect the fuel tanks too, which means it’s huge, and thus heavy. However,
we’ll be super optimistic and say the airframe can be enlarged to hold it all
by simply adding 147 tons (If that sounds like a lot, it isn’t, as we’ll see in
a bit). So, a surface-to-surface MCT with 100 tons of cargo masses, unfueled,
at a very optimistic 647 tons. That’s our dry weight – everything but fuel.
There’s also the matter of internal pressurized volume.
Again using an airliner as an example, the 747 has around 32,000 cubic feet –
and so, for comparison, does ISS. ISS has a crew of 6, though could handle a
few more. However, let’s use the 747 – ISS internal volume and assume it’d be
enough for 100 people. (for comparison, the 747 carries 500, but does so in
such cramped confines that a 6 hour flight in one is bad, and a 15 hour flight
is unmitigated hell). Even if we postulate horrific crowding, you’d need at
least that much volume (probably more) to accommodate 100 people for a
months-long journey. However, we’ll assume the aforementioned magic engineering
and say that a surface to surface MCT (which has to deal with reentry and landing
on both earth and Mars, as well as long-duration deep space capability) will
mass 647 tons.
So, let’s say you have your surface-to-surface MCT in LEO,
and want to go to Mars. How much fuel do you need? Fortunately, that’s easy to
figure out; the rocket equation. The optimal Trans Mars Injection burn (least
delta/V, but a rare window) is 4.7 KPS. This assumes essentially zero
propulsion for Mars orbital insertion (which can be done via aerobraking or
multi pass aerocapture) and the landing itself. For the latter, we’ll be
optimistic and say .3 kps (which is less than the F9R recovery profile, even
without full boostback). That gives us a
needed delta/V of 5kps, so time to tank up! Calculating how much is easy; we’ll
assume 380 ISP for Raptor Vac, the most likely engine choice. We already have
our dry mass of 647 tons. The rocket equation gives a fuel requirement of 1833
tons (, but there are always boiloff losses, margins, etc, to consider, so add
10%, and we need 2016 tons of fuel. That gives us a fueled MCT mass in Leo of
2663 tons (about 3X the mass of ISS).
Now, how do we get a 647 ton MCT to Leo? This is what’s
called, in engineering terms, a bit of a problem. BFR is going to need to be
really, really, really big. A Saturn 5 could put 118 tons into LEO. However,
MCT will take a performance hit due to reusability, so at best you’ll need a
BFR significantly larger than a Saturn 5 just to equal a Saturn 5’s payload.
But, our postulated MCT, unfueled, is 6 times the capability of a Saturn 5. A
BFR that could launch it thus can’t be 3 cores, each the size of a Saturn 5.
You’re going to need something massing 10 times the Saturn 5 – far larger than
any estimate I’ve ever seen for BFR, and also beyond the realm of the plausible
(either fiscally or physically).
You’re also going to need the equivalent of 17 Saturn 5
launches just to fuel up one MCT. You’ll also need one hell of a lot of ISRU
fuel production on Mars to refuel it once it gets there.
All this begs the question; why do it that way and spend so
much fuel boosting, for example, the earth-entry structures all the way to Mars
and back? Or the Mars entry and landing systems all the way to Earth and back?
Why not do it much more economically from every perspective, and do so in a way
that gives you a far more versatile system? It’s the same problem that makes
Orion such a pathetic design; you’re hauling along a huge mass because you’re
treating your living space as the reentry vehicle. Far, far better to use a
very small RV, like Soyuz’s, for the RV, and use a lightweight hab for the
rest.
So, given the implausibility above of a surface-to-surface
MCT, what might an optimized MCT-BFR system look like? MCT would not land on
either earth or mars; it would be a space-only vehicle, thus saving enormous
mass. A good example of such a craft would be a space station module; an
inflatable one, such as Bigelow is building… let’s use their BA-330 design for
a starting point. Once inflated, it’s big; 11,654 square feet internal volume
(for comparison, ISS has 32,333, roughly akin to a 747) It’s a space station
module, thus has life support, etc, included. Mass? 20 tons. It’s not big
enough though… so you’d need more. Let’s assume 4 linked together. That gives
you redundancy too, plus an internal volume of 46,616 square feet. Mass? 80
tons empty – which interestingly, is 4/5th the mass figure SpaceX
gives for MCT- 100 tons empty. That’s also far more realistic an internal
volume for 100 people, plus the needed life support equipment and consumables.
It’s designed as a space station, so it has the ability, inherently, to exist
in space long-term, no need to land.
However- we need propulsion and fuel. So, add a 5th
inflatable module, because inflatables would be ideal for fuel storage in space
– why waste the mass needed for a rigid tank like the Shuttle ET? I’ll assume
20 tons (it’d be a lot lighter than a hab module, but it’d need a Raptor engine
and thrust structure – perhaps two Raptors, for redundancy)
Okay, we have our 5-module MCT. Now, we need to get it to
Mars. We’ll do the same rocket equation as above, and so our 200 ton (100 ton
empty mass, plus 100 tons of cargo or humans plus supplies) MCT needs 565 tons
of propellant to push it through TMI from LEO. However, this MCT doesn’t land
on Earth or Mars, so there’s no reason to waste Delta-V by going deep into the
gravity wells of Earth and Mars; high-energy orbits will be far better. Let’s
use geosynchronous transfer orbit as an example for Earth, and a similar orbit
for Mars. That has a major impact on the needed Delta/V. Instead of 5 kps
propulsive ability (Leo to Mars landing, assuming aerobraking) we need 1.3 kps
(assuming multipass airocapture into Mars GTO). Now, what does that do to our
fuel requirement? It reduces it from 565 tons to 85 tons. (Quite a big difference from the 2016 tons of
fuel a surface-to-surface MCT would need to get from LEO to Mars! It’s reduced
our fuel (all of it very expensive upmass) needed by 96%). We also save on
margins by omitting the need to haul decent fuel (with resulting losses) all
the way to Mars.
However, we still need to get to and from the surface of
Mars. The surface-to-surface MCT could do it, but the space-only one can’t –
it’s limited to orbit. Fortunately, the answer lies in the launch vehicle, the
BFR; the reusable upper stage, to be exact. Any upper stage that can return
from orbit to Earth is going to be light, about the density/volume ratio of an
empty beer can. Thus, even in Mars’ very thin atmosphere, terminal velocity
should be in the low supersonic range. That makes for an easy propulsive
landing (it already has a heat shield, due to needing one to reenter on Earth).
It already has landing legs, too. With some minor modifications (incorporated
into the original design), it should be able to land on Mars, and carry a
payload while doing so. Once on Mars, it can fuel up from ISRU, and function as
a very capable SSTO – with at least the same payload as the full BFR’s max
capacity from Earth – Mars’ far lower gravity, and thus orbital speed, makes SSTO
easy. The MCT would arrive in an
eccentric (Basically, Martian GTO) Mars orbit, and be met by a BFR upper stage
from the surface. If the stage had a payload shroud, cargo could be placed
within it for the trip to the surface. A pressurized compartment would do the
same for people, or, something akin to Red Dragons could function as landers
(and then be returned to orbit by the BFR stage, which could loft more than
enough to carry 100 people down – for a trip of less than an hour, 10 could fit
in a Dragon).
So, a BFR upper stage, you have your needed Mars
ascent/decent vehicle.
Now what about getting the MCT from Mars to Earth? Easier. The
BFR stage brings fuel and cargo and/or passengers. You then need 1.1 kps, with multipass
aerocapture (which does not require heat shielding) to get from Mars GTO to
Earth, and brake into GTO at Earth. From there, high capacity (10 seat) Dragons
could deliver any crew to earth, or a simple, small, orbital tug could transfer
any cargo to LEO (again using areocapture). A likely cargo (seeing as how MCT
would otherwise be coming back empty) would be fuel for the fuel depot in GTO,
or one in LEO – it takes a lot less delta/v to get to Leo from the surface of
Mars than it does from the surface or Earth.
Given the low delta-V requirements from GTO to Martian GTO,
you could add 1 KPS to do a fast transfer. (something else SpaceX has
mentioned). This would also ease the launch window timeframe significantly (my
calcs in this post are based on the once-in-2.2 years optimal Mars window).
Therefore, my hunch is that the MCT will either be, or be
very similar to, four or five BA 330 modules. Going further, the four manned
ones could be linked in pairs, separated by a tether, and spun up to generate
artificial G. Generating Mars G would be even easier, as it’s 38% of Earth’s.
This would acclimatize crew to Mars G en route, while avoiding the debilitating
effects of prolonged weightlessness. Also,
artificial G will probably be required in order to get the breeding stock of
food animals (which any Mars colony will have to have) to Mars. No need to take
a whole flock of chickens or drove of pigs, for example, but you’ll need to
take two or three plus a few hundred frozen embryos.
That brings us back to the BFR; how big does it need to be?
For the space-only MCT, it really only has to get, at most, about 100 tons to
GTO, which makes it about one and a half Saturn 5 class in capacity – well
within the speculated range for the BFR. That’d also give its upper stage the
capability (assuming ISRU refueling on Mars) to function as a Mars
ascent/decent SSTO vehicle with 100 or more tons of payload.
As a further piece of evidence supporting my hunch that
that’s what they have in mind for some BFR upper stages, SpaceX has said one of
the reasons for choosing methane was the ability to obtain it via ISRU on Mars.
So, unless part of the BFR is intended to go to Mars, that makes little sense
(otherwise, only a surface-to-surface MCT would need Methlox, and could use
smaller engines).
Using this architecture, the result would be a fairly
low-cost, reusable multi-vehicle Mars transportation system. It would have
cargo capacity in both directions, allowing for the Mars colony to export
ISRU-derived commodities (Fuel, oxidizer, water, food) to Earth orbit (a good
fiscal basis for an economically self-supporting colony), due to the fact that
it takes far less propulsive delta-V to get from Mars surface to LEO than to do
so from Earth. Granted, there isn’t currently
a demand, but the near future should see such a demand, in the form of several
LEO and higher space stations, fuel depots, etc. (the advent of the cheap-per-pound
launch capacity BFR promises would help create that market).
Major caveat; I’m writing this post in the belief (If I’m in
error, please correct me) that it contradicts nothing SpaceX has recently officially
announced regarding BFR and MCT. I do however discount some SpaceX
announcements from the more distant past, due to SpaceX's penchant for changing
plans due to encountering physical and fiscal limitations during R&D. They
have always done this. For example, their recovery method for F9R looks nothing
like their announced parachute-based splashdown concept they tried with F9 1.0.
Also, Falcon Heavy will look very different from the F9 1.0 based FH they
originally announced. They’ve also changed the specs on Raptor massively, more
than once. The only thing I’m accusing them of is having a sane approach to
engineering, one that’s not needlessly bound by their past estimates. I consider
this very commendable. However, it does means that outside speculators, such as
myself, sometimes need to assume that some of SpaceX’s announcements may have a
short shelf life. Thus, I’m taking such liberties in my speculation here.
A couple of definitions for terms used here; Aerobraking is
using a partial entry to dissipate velocity and enter orbit (or set up for full
entry). Aerocapture is multiple passes through the atmospheric fringes, such as
MRO used to enter Mars orbit. Aerobraking requires a heat shield, while
aerocapture does not. Both save on propulsive delta-V.
Export industry for Mars
A couple of posts below, Ken lays out a good argument for developing industry on Mars.
The only point I disagree with is the assumption that there's no market for exporting products from Mars.
An export industry is an industry, and there is, or soon will be, a very viable market; consumables.
Let's look at fuel depots in LEO for just one example; they're going to happen, and fairly soon. So, how does one get fuel to the fuel depot? Currently, plans are to launch it from Earth. This seems logical, because low earth orbit is only around 200 miles from Earth's surface. However, when it comes to spaceflight, the number that matters most is propulsive delta-V, not distance. To get to LEO, you have to accelerate your payload by around 9.2 kilometers per second (8 kps for orbital speed, and about 1.1 to 1.2 for gravity and aerodynamic losses).
Therefor, if you have a fuel depot for, say, methane and oxygen, or hydrogen and oxygen, getting it to LEO from Earth is a hard hill to climb. So, why not get it from Mars? That sounds preposterous because Mars is a long way from Leo, but that's in distance, not in Delta-V, and Delta-V is what counts.
Launching from the surface of Mars to low Martian orbit takes 4.1 kps, a lot less than the 9.2 from Earth to Leo. But, how do you get from low Mars orbit to LEO? Part of that is propulsive Delta/v - 2.3 kps to get you on an earth-transfer trajectory. So, your total propulsive delta-V? 6.4 kps. From Earth transfer, you can aerocapture (no shielding required) into LEO. So, your fuel arrives in LEO having needed 6.4 kps propulsive Delta-V compared to 9.2 from Earth. That's quite a savings, but it's only a small part of the benefits. The rest is in launch architecture.
Take the F9 upper stage as an example. If you had it on the surface of Mars, not only could it do single stage to orbit with what, on earth, is its max payload, it could do Mars surface to earth transfer. (Falcon 9 stage sep occurs around mach 6, so 1.7 kps, and though the first stage has dealt with about half the gravity losses, the second stage has to supply around 6.8kps)
What this means in practice is that your Mars launch vehicle can be single stage to orbit - far, far cheaper and easier than staging, because it eliminates the need for the 90% of the vehicle you discard at staging (and even with reusability, this cost dynamic applies. a 747 and a Lear Jet are both reusable, but the 747 costs one hell of a lot more to buy and operate.)
With ISRU on Mars, you could easily produce methane and oxygen, launch them to low Mars orbit, where you use them to fill up a supercold transfer tank. (you avoid boil off losses by keeping the tank very, very cold, easy to do in space; you have a layer of aluminum foil a few feet from the tank, between it and the sun). Once the tanker is filled, a small rocket motor using some of that fuel boosts it through the trans-earth burn.
Hydrogen/oxygen is a bit trickier due to the temperature demands for Hydrogen, plus the tankage size needed. It's probably be more efficient to ship it as water, and electrolyze it as needed in earth orbit.
And speaking of water, that, too, is a commodity that'll be needed as space infrastructure grows. And that gets us to food, which is already a significant amount of upmass for ISS, and the demand for it will rise as we see more human occupation of LEO as well as further out.
So, given all of the above, we have an economic model for a major export industry on Mars. However, there's an even bigger economic factor, one that harks back to the birth of Transatlantic trade. The early colonies in North America were founded with people and supplies from Europe, and initially, the only value returned was that of the land in the New World. However, the ships delivering supplies were going back empty, and that's free cargo capacity, then as now. Back then, cash crops such as tobacco began to fill those empty holds. The same dynamic applies to a Mars colony; the vehicles delivering colonists and supplies to Mars will be going back to earth empty at first, so that's basically free cargo capacity. For a colony on Mars, you'll already have ISRU production of water, fuel, etc, and for vehicles like MCT, which is supposed to be reusable (and thus must return to earth), you'll have 100 tons cargo capacity to LEO. Whether MCT is able to land on Mars (I personally doubt it) of is a space-only craft, you'll have some kind of Mars-ascent system. The capability is inherent in the design concept of the raptor-powered heavy lifter; an upper stage of that reusable launch vehicle would have the inherent ability to land on Mars, refuel, and do either single stage to Mars orbit, or, single stage from Mars surface to Leo. So, to use the early transatlantic trade analogy, you'll already have the empty holds returning to Earth, so why not use them for an export industry?
Later, as the Mars colony's capabilities expand, if they're able to build pressurized habitats for Mars (they'll have to be able to do that) they can just as easily build them for space, and put them where they are needed for far, far less cost than launching them from earth. It might also be worth their while to build fuel depots (which are largely just large tanks), fill them in Mars orbit, and send them earthward - because one of the many advantages of launching from Mars is you're not limited by the diameter of the launch vehicle or payload shroud (restrictions imposed by earth's atmosphere). This of course applies to habitat design as well; if somebody wants, say, a 100 foot diameter sphere, or a segment of a large wheel, that's easy to launch from Mars but impossible from Earth, due to the atmosphere.
The only point I disagree with is the assumption that there's no market for exporting products from Mars.
An export industry is an industry, and there is, or soon will be, a very viable market; consumables.
Let's look at fuel depots in LEO for just one example; they're going to happen, and fairly soon. So, how does one get fuel to the fuel depot? Currently, plans are to launch it from Earth. This seems logical, because low earth orbit is only around 200 miles from Earth's surface. However, when it comes to spaceflight, the number that matters most is propulsive delta-V, not distance. To get to LEO, you have to accelerate your payload by around 9.2 kilometers per second (8 kps for orbital speed, and about 1.1 to 1.2 for gravity and aerodynamic losses).
Therefor, if you have a fuel depot for, say, methane and oxygen, or hydrogen and oxygen, getting it to LEO from Earth is a hard hill to climb. So, why not get it from Mars? That sounds preposterous because Mars is a long way from Leo, but that's in distance, not in Delta-V, and Delta-V is what counts.
Launching from the surface of Mars to low Martian orbit takes 4.1 kps, a lot less than the 9.2 from Earth to Leo. But, how do you get from low Mars orbit to LEO? Part of that is propulsive Delta/v - 2.3 kps to get you on an earth-transfer trajectory. So, your total propulsive delta-V? 6.4 kps. From Earth transfer, you can aerocapture (no shielding required) into LEO. So, your fuel arrives in LEO having needed 6.4 kps propulsive Delta-V compared to 9.2 from Earth. That's quite a savings, but it's only a small part of the benefits. The rest is in launch architecture.
Take the F9 upper stage as an example. If you had it on the surface of Mars, not only could it do single stage to orbit with what, on earth, is its max payload, it could do Mars surface to earth transfer. (Falcon 9 stage sep occurs around mach 6, so 1.7 kps, and though the first stage has dealt with about half the gravity losses, the second stage has to supply around 6.8kps)
What this means in practice is that your Mars launch vehicle can be single stage to orbit - far, far cheaper and easier than staging, because it eliminates the need for the 90% of the vehicle you discard at staging (and even with reusability, this cost dynamic applies. a 747 and a Lear Jet are both reusable, but the 747 costs one hell of a lot more to buy and operate.)
With ISRU on Mars, you could easily produce methane and oxygen, launch them to low Mars orbit, where you use them to fill up a supercold transfer tank. (you avoid boil off losses by keeping the tank very, very cold, easy to do in space; you have a layer of aluminum foil a few feet from the tank, between it and the sun). Once the tanker is filled, a small rocket motor using some of that fuel boosts it through the trans-earth burn.
Hydrogen/oxygen is a bit trickier due to the temperature demands for Hydrogen, plus the tankage size needed. It's probably be more efficient to ship it as water, and electrolyze it as needed in earth orbit.
And speaking of water, that, too, is a commodity that'll be needed as space infrastructure grows. And that gets us to food, which is already a significant amount of upmass for ISS, and the demand for it will rise as we see more human occupation of LEO as well as further out.
So, given all of the above, we have an economic model for a major export industry on Mars. However, there's an even bigger economic factor, one that harks back to the birth of Transatlantic trade. The early colonies in North America were founded with people and supplies from Europe, and initially, the only value returned was that of the land in the New World. However, the ships delivering supplies were going back empty, and that's free cargo capacity, then as now. Back then, cash crops such as tobacco began to fill those empty holds. The same dynamic applies to a Mars colony; the vehicles delivering colonists and supplies to Mars will be going back to earth empty at first, so that's basically free cargo capacity. For a colony on Mars, you'll already have ISRU production of water, fuel, etc, and for vehicles like MCT, which is supposed to be reusable (and thus must return to earth), you'll have 100 tons cargo capacity to LEO. Whether MCT is able to land on Mars (I personally doubt it) of is a space-only craft, you'll have some kind of Mars-ascent system. The capability is inherent in the design concept of the raptor-powered heavy lifter; an upper stage of that reusable launch vehicle would have the inherent ability to land on Mars, refuel, and do either single stage to Mars orbit, or, single stage from Mars surface to Leo. So, to use the early transatlantic trade analogy, you'll already have the empty holds returning to Earth, so why not use them for an export industry?
Later, as the Mars colony's capabilities expand, if they're able to build pressurized habitats for Mars (they'll have to be able to do that) they can just as easily build them for space, and put them where they are needed for far, far less cost than launching them from earth. It might also be worth their while to build fuel depots (which are largely just large tanks), fill them in Mars orbit, and send them earthward - because one of the many advantages of launching from Mars is you're not limited by the diameter of the launch vehicle or payload shroud (restrictions imposed by earth's atmosphere). This of course applies to habitat design as well; if somebody wants, say, a 100 foot diameter sphere, or a segment of a large wheel, that's easy to launch from Mars but impossible from Earth, due to the atmosphere.
Friday, January 23, 2015
AmericaSpace Chickenshits still afraid of free speech
I'd spoof them if it were important, but it isn't.
Thursday, January 22, 2015
MCT payload
Elon promises too tell us more.
The article says MCT will have a 100 metric ton payload. Previously we learned it will have up to 100 colonists. That makes the math easy!
I'm guessing a ballpark of $500 million per launch. So if first landing has 10 colonists that's almost 10 tons per crew. Much better than the 2 ton per I consider minimal.
My mission of a dozen for $2b just got blown out of the water.
MCT cargo about $5m per ton vs. red lander $60m per ton... quite an impressive improvement.
Bad news? This lower the value and amount of personal possessions. A half ton each (the other half being themselves, spacesuit and short term consumables) means personal property may be worth something less than a million but still provide a good financial start.
My speculations in general become more possible as costs lower. This should also cause the value of real property on mars to appreciate faster. I may actually see people living on mars before I die?
The article says MCT will have a 100 metric ton payload. Previously we learned it will have up to 100 colonists. That makes the math easy!
I'm guessing a ballpark of $500 million per launch. So if first landing has 10 colonists that's almost 10 tons per crew. Much better than the 2 ton per I consider minimal.
My mission of a dozen for $2b just got blown out of the water.
MCT cargo about $5m per ton vs. red lander $60m per ton... quite an impressive improvement.
Bad news? This lower the value and amount of personal possessions. A half ton each (the other half being themselves, spacesuit and short term consumables) means personal property may be worth something less than a million but still provide a good financial start.
My speculations in general become more possible as costs lower. This should also cause the value of real property on mars to appreciate faster. I may actually see people living on mars before I die?
The idiocy of smart guys
If you need an asset in orbit, common sense tells ya it should be put there at lowest cost. The clearest explanation why ARM makes no sense.
Monday, January 19, 2015
Industry on mars
Edward Wright makes this astounding statement...
[clarification: Ed and I are actually in complete agreement that mars has no export of mass that would be profitable. I simply don't limit industry to exports only.]
[Update: CJ provides the answer Ed was looking for.]
Is he defining industry as anything they can't currently do on mars? Is anything not involving earth/mars import/export not industry?
Ok, now let's show how industrial development on mars may occur...
A dozen permanent colonists arrive in mars orbit. They do some prep of there landing site with rover/tractors. Then four of the dozen land for more site prep followed soon after by the remaining colonists.
These dozen have everything they need for basic ISRU life support. They can do some exploring (both directly and remotely in a limited range, satellites provider farther views) but it is a very modest life with many desires unfulfilled. They have habitats and farms but little food diversity. They have energy to survive, but little for industry. Water and oxygen are abundant. Fuel for vehicles will be abundant as well. Machines will require maintenance and repair eventually beyond the replacement materials they brought with them. Recycling and 3D printing having its limitations. They will need to develop local resources but that will always be a progressive operation.
Living on mars will tell them by experience what priorities are, which they will communicate to the next missions leaving earth.
What is industry? It doesn't start out full blown. It grows to fill the needs of its customers. What do they need more of? Energy. Any industry is going to need energy so that will be the first priority. Electricity is one convenient form. Methane and oxygen would be another. They will extract iron from the dust for mechanisms. People will specialize and trade. Eventually they can make more solar panels but steam is easier at first. So they concentrate solar energy for steam. The steam powers a generator (car alternator sized at first, getting bigger over time.) They'll need more batteries, using whatever chemical elements they find to use. They will have a lot of options, but it will depend on what they find. Battery making is an industry that some will specialize in. They will trade those batteries, not give them away.
Do I really need to identify every modern item of trade? It all works the same. New arrivals will bring things they haven't yet developed on mars. This is a source of wealth for all new arrivals.
How will existing colonists pay for this new stuff? With things they produce on mars so new arrivals don't have to waste mass bringing it with them. This is the basis of all economics.
There is no industry that could not eventually evolve. The pace is faster as more millionaires arrive (everyone that arrives with personal property chosen well will be a millionaire on landing.)
Why? Because trade for earth products will compete. Do I buy from the new arrivals or pay $60k per kg to get it delivered from earth? Can I build it myself or will the new colonist accept something less than $60k. Will my neighbor buy it for more leaving me out? Hey, I got that 50 inch tv for only 4 grand!
Can I call my lawyer and accuse them of price gouging... wait, no lawyers. Can I steal it? Oh no, everybody knows everything in a small town.
Trade works, unless you have a very blinded concept of economics.
Tell me again what industry they could not develop on mars?
[clarification: Ed and I are actually in complete agreement that mars has no export of mass that would be profitable. I simply don't limit industry to exports only.]
[Update: CJ provides the answer Ed was looking for.]
You can’t identify a single industry that you expect to establish on Mars?Amazing! Ed is a really smart guy so how could he make such a statement? Because there isn't any possible industry that couldn't be established on mars. Before getting to that, let's consider the false assumptions that might have lead to this amazing statement.
Is he defining industry as anything they can't currently do on mars? Is anything not involving earth/mars import/export not industry?
Ok, now let's show how industrial development on mars may occur...
A dozen permanent colonists arrive in mars orbit. They do some prep of there landing site with rover/tractors. Then four of the dozen land for more site prep followed soon after by the remaining colonists.
These dozen have everything they need for basic ISRU life support. They can do some exploring (both directly and remotely in a limited range, satellites provider farther views) but it is a very modest life with many desires unfulfilled. They have habitats and farms but little food diversity. They have energy to survive, but little for industry. Water and oxygen are abundant. Fuel for vehicles will be abundant as well. Machines will require maintenance and repair eventually beyond the replacement materials they brought with them. Recycling and 3D printing having its limitations. They will need to develop local resources but that will always be a progressive operation.
Living on mars will tell them by experience what priorities are, which they will communicate to the next missions leaving earth.
What is industry? It doesn't start out full blown. It grows to fill the needs of its customers. What do they need more of? Energy. Any industry is going to need energy so that will be the first priority. Electricity is one convenient form. Methane and oxygen would be another. They will extract iron from the dust for mechanisms. People will specialize and trade. Eventually they can make more solar panels but steam is easier at first. So they concentrate solar energy for steam. The steam powers a generator (car alternator sized at first, getting bigger over time.) They'll need more batteries, using whatever chemical elements they find to use. They will have a lot of options, but it will depend on what they find. Battery making is an industry that some will specialize in. They will trade those batteries, not give them away.
Do I really need to identify every modern item of trade? It all works the same. New arrivals will bring things they haven't yet developed on mars. This is a source of wealth for all new arrivals.
How will existing colonists pay for this new stuff? With things they produce on mars so new arrivals don't have to waste mass bringing it with them. This is the basis of all economics.
There is no industry that could not eventually evolve. The pace is faster as more millionaires arrive (everyone that arrives with personal property chosen well will be a millionaire on landing.)
Why? Because trade for earth products will compete. Do I buy from the new arrivals or pay $60k per kg to get it delivered from earth? Can I build it myself or will the new colonist accept something less than $60k. Will my neighbor buy it for more leaving me out? Hey, I got that 50 inch tv for only 4 grand!
Can I call my lawyer and accuse them of price gouging... wait, no lawyers. Can I steal it? Oh no, everybody knows everything in a small town.
Trade works, unless you have a very blinded concept of economics.
Tell me again what industry they could not develop on mars?
Saturday, January 17, 2015
Preparing for my trip.
My alternator is now installed (which perversely now has my check engine idiot light lit.) I just bought a new fanbelt tension pulley because that's the next bearing due to fail. Replaced my idler pulley (and belt) on my last failed trip. Pep Boys wanted $300 for ten minutes of labor. They didn't get it from me.
My oil change is a bit overdue, but I have a new filter.
Two new front tires on payday and my Jimmy should be ready for the trip. Then I wait a month for enough money to go (this next paycheck is already spent.) I expect to borrow some more to give me a bit more security in case of trouble.
I hope to tour SpaceX in Hawthorne and Bigelow in NV. I hope gas prices remain low (under $2 in Phoenix.) Also hope to get to Sacramento and Los Angeles (haven't been to the pit in decades but Hawthorne is right there.)
Still need to needle my local attorney for the trust attorney referral. Taking my money doesn't require him to take me seriously, but he fakes it pretty well.
Also working on my 13 ton (does not require a heavy) charter yacht in space strategy (LEO and lunar excursions.) A good potential ROI (less than a year) might get some investor group bites? Don't need to mention mars as the real goal for this (sidestepping the giggle factor.) A real ship in orbit allows others to see some possibilities as real. The trust could pay for the total cost of putting it in orbit (about the same cost as a single colonist travel ticket.)
So I wrote an email to ILC Dover about the cost of a prelim design for a ship to a spec I gave them. So far just got a robo-response. Will draw it myself if I must (using existing systems as models.) Pen plotters have gone the way of the dinosaurs ( I am so old) but CAD software is easy to get.
Tangibles for moving forward...
My oil change is a bit overdue, but I have a new filter.
Two new front tires on payday and my Jimmy should be ready for the trip. Then I wait a month for enough money to go (this next paycheck is already spent.) I expect to borrow some more to give me a bit more security in case of trouble.
I hope to tour SpaceX in Hawthorne and Bigelow in NV. I hope gas prices remain low (under $2 in Phoenix.) Also hope to get to Sacramento and Los Angeles (haven't been to the pit in decades but Hawthorne is right there.)
Still need to needle my local attorney for the trust attorney referral. Taking my money doesn't require him to take me seriously, but he fakes it pretty well.
Also working on my 13 ton (does not require a heavy) charter yacht in space strategy (LEO and lunar excursions.) A good potential ROI (less than a year) might get some investor group bites? Don't need to mention mars as the real goal for this (sidestepping the giggle factor.) A real ship in orbit allows others to see some possibilities as real. The trust could pay for the total cost of putting it in orbit (about the same cost as a single colonist travel ticket.)
So I wrote an email to ILC Dover about the cost of a prelim design for a ship to a spec I gave them. So far just got a robo-response. Will draw it myself if I must (using existing systems as models.) Pen plotters have gone the way of the dinosaurs ( I am so old) but CAD software is easy to get.
Tangibles for moving forward...
- Ship CAD drawing, cost estimate and leasing potential.
- Trust document (and trustees?)
- Webpage to finance trust (need many ducks lined up first.)
Now if only my truck doesn't break down this time?
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