Flexible Path? What?

Augustine Commission pretty much recommends in its report what it calls
"Flexible Path" - wide array of potential targets to be visited by manned
spacecraft as a precursor to manned Mars mission. These include Near Earth Asteroids,
moons of Mars, Lagrange points etc. It has got blogosphere all excited.

Is there something I'm not getting there? Because quite frankly, that sounds like
biggest idiocy I've heard for long long time. I mean, what there is in Lagrange points
for humans to do? They are just empty space. Manned mission to NEO sounds like one of
big cost for limited return. And why would anyone want a mission where astronauts go through
all the trouble and tedous transit to Mars, only not land there?

Another thing: Augustine Commission supports orbital refueling to get around launch
vehicle limitations. Is this really practical? Because it sure doesn't sound like it would be.

On Sat, 31 Oct 2009 11:08:47 +0000 (UTC), Yama
wrote:

Augustine Commission pretty much recommends in its report what it calls
"Flexible Path" - wide array of potential targets to be visited by manned
spacecraft as a precursor to manned Mars mission. These include Near Earth Asteroids,
moons of Mars, Lagrange points etc. It has got blogosphere all excited.

I call it the "Build the Infrastructure Now, Decide Where To Go Later"
approach. Basically, the AC saw that the current "Back to the Moon, On
To Mars" plan simply doesn't fit the available budget (because NASA
chose or was forced by Congress to choose a hopelessly expensive
infrastructure). Even "Flexible Path" requires a budget increase (just
not as great an increase.) So the AC gave Pres. Obama an option that
keeps exploration on the table without 50% budget increases.

Is there something I'm not getting there? Because quite frankly, that sounds like
biggest idiocy I've heard for long long time.

You must not be listening to the Public Health Care debate and the
idiocy coming out of both sides of that debate. :-)

I mean, what there is in Lagrange points
for humans to do?

Service telescopes, in theory. Build a staging area/propellant depot
for lunar or deep space missions.

They are just empty space. Manned mission to NEO sounds like one of
big cost for limited return. And why would anyone want a mission where astronauts go through
all the trouble and tedous transit to Mars, only not land there?

Remote operation of rovers with only a second or two time delay.

Another thing: Augustine Commission supports orbital refueling to get around launch
vehicle limitations. Is this really practical?

Progress has been performing orbital refueling for 30 years now, at
the Salyuts, Mir and ISS.

90% or more of any deep space mission is propellant. Propellant is
cheap (compared to hardware). If we can use cheap, modestly reliable
rockets (90% reliablity instead of 99.5%... if we lose one now and
then, who cares? its mostly just LOX) to deliver propellant to a
depot, we should be able to cut the costs of the missions and probably
defer development of the hugely expensive Ares V megarocket. The depot
could potentially grow to become a way station for payloads bound for
geosynchronous orbit, enabling even bigger comsats. The fuel delivery
market could finally foster development of true Reusable Launch
Vehicles, which could radically reduce cost-to-orbit over the long
run.

We should at least try.

Brian

Brian Thorn wrote:
: On Sat, 31 Oct 2009 11:08:47 +0000 (UTC), Yama
: wrote:
: Augustine Commission pretty much recommends in its report what it calls
: "Flexible Path" - wide array of potential targets to be visited by manned
: spacecraft as a precursor to manned Mars mission. These include Near Earth Asteroids,
: moons of Mars, Lagrange points etc. It has got blogosphere all excited.

: I call it the "Build the Infrastructure Now, Decide Where To Go Later"
: approach. Basically, the AC saw that the current "Back to the Moon, On
: To Mars" plan simply doesn't fit the available budget (because NASA
: chose or was forced by Congress to choose a hopelessly expensive
: infrastructure). Even "Flexible Path" requires a budget increase (just
: not as great an increase.) So the AC gave Pres. Obama an option that
: keeps exploration on the table without 50% budget increases.

I just don't see where the savings are supposed to come. Quite the contrary,
all these proposed targets would need specialized craft and equipment to
design and build. A Phobos mission would be nearly as expensive and difficult for
Mars mission.

It seems to me that they were proposed because they SOUND easier.

Not to mention that science return from asteroid mission is going to be
fraction what can be gained from Moon or Mars mission.

: I mean, what there is in Lagrange points
: for humans to do?

: Service telescopes, in theory. Build a staging area/propellant depot
: for lunar or deep space missions.

Except that current and projected Lagrange telescopes are not designed
to be serviceable...

: They are just empty space. Manned mission to NEO sounds like one of
: big cost for limited return. And why would anyone want a mission where astronauts go through
: all the trouble and tedous transit to Mars, only not land there?

: Remote operation of rovers with only a second or two time delay.

I see absolutely no point whatsoever sending people to two-year mission merely
to act as remote rover operators.

: Another thing: Augustine Commission supports orbital refueling to get around launch
: vehicle limitations. Is this really practical?

: Progress has been performing orbital refueling for 30 years now, at
: the Salyuts, Mir and ISS.

: 90% or more of any deep space mission is propellant. Propellant is
: cheap (compared to hardware). If we can use cheap, modestly reliable
: rockets (90% reliablity instead of 99.5%... if we lose one now and
: then, who cares? its mostly just LOX)

But doesn't ISS etc use hypergolic fuels, not LOX?

Yama wrote:
Brian Thorn wrote:
: On Sat, 31 Oct 2009 11:08:47 +0000 (UTC), Yama
: wrote:
: Augustine Commission pretty much recommends in its report what it calls
: "Flexible Path" - wide array of potential targets to be visited by manned
: spacecraft as a precursor to manned Mars mission. These include Near Earth Asteroids,
: moons of Mars, Lagrange points etc. It has got blogosphere all excited.

: I call it the "Build the Infrastructure Now, Decide Where To Go Later"
: approach. Basically, the AC saw that the current "Back to the Moon, On
: To Mars" plan simply doesn't fit the available budget (because NASA
: chose or was forced by Congress to choose a hopelessly expensive
: infrastructure). Even "Flexible Path" requires a budget increase (just
: not as great an increase.) So the AC gave Pres. Obama an option that
: keeps exploration on the table without 50% budget increases.

I just don't see where the savings are supposed to come. Quite the contrary,
all these proposed targets would need specialized craft and equipment to
design and build. A Phobos mission would be nearly as expensive and difficult for
Mars mission.

Are you nuts? JAXA could do it.

It seems to me that they were proposed because they SOUND easier.

They are physically much easier.

Not to mention that science return from asteroid mission is going to be
fraction what can be gained from Moon or Mars mission.

We have spacecraft on Mars right now.

: I mean, what there is in Lagrange points
: for humans to do?

: Service telescopes, in theory. Build a staging area/propellant depot
: for lunar or deep space missions.

Except that current and projected Lagrange telescopes are not designed
to be serviceable...

That's the whole point of going there, so we know we can service them.

: They are just empty space. Manned mission to NEO sounds like one of
: big cost for limited return. And why would anyone want a mission where astronauts go through
: all the trouble and tedous transit to Mars, only not land there?

Because you are demonstrably incompetent and unfunded to do so.
: Remote operation of rovers with only a second or two time delay.

I see absolutely no point whatsoever sending people to two-year mission merely
to act as remote rover operators.

: Another thing: Augustine Commission supports orbital refueling to get around launch
: vehicle limitations. Is this really practical?

: Progress has been performing orbital refueling for 30 years now, at
: the Salyuts, Mir and ISS.

: 90% or more of any deep space mission is propellant. Propellant is
: cheap (compared to hardware). If we can use cheap, modestly reliable
: rockets (90% reliablity instead of 99.5%... if we lose one now and
: then, who cares? its mostly just LOX)

But doesn't ISS etc use hypergolic fuels, not LOX?

On Sun, 1 Nov 2009 12:49:46 +0000 (UTC), Yama
wrote:

: Augustine Commission pretty much recommends in its report what it calls
: "Flexible Path" - wide array of potential targets to be visited by manned
: spacecraft as a precursor to manned Mars mission. These include Near Earth Asteroids,
: moons of Mars, Lagrange points etc. It has got blogosphere all excited.

: I call it the "Build the Infrastructure Now, Decide Where To Go Later"

I just don't see where the savings are supposed to come.

Canceling Altair. Scaling-down Ares V (sized for Moon/Altair) to
existing ET diameter and 4- or 5-segment SRB (vs. 5 1/2 segment now
planned.) Cancel Ares I and move everything to this Ares V-Lite.

Big savings and a more robust launch system.

Quite the contrary,
all these proposed targets would need specialized craft and equipment to
design and build. A Phobos mission would be nearly as expensive and difficult for
Mars mission.

The simplest asteroid-rendezvous concepts simply call for two Orions
docked end-to-end. You don't really need a lander for a small
asteroid, its really just proximity operations due to the low gravity
(think NEAR's "landing".)

It seems to me that they were proposed because they SOUND easier.

And they defer the high-cost mission modules (landers, labs,
what-have-you) until later.

Not to mention that science return from asteroid mission is going to be
fraction what can be gained from Moon or Mars mission.

But potentially much more important if one is discovered on an impact
trajectory.

Except that current and projected Lagrange telescopes are not designed
to be serviceable...

Chicken meet Egg. There are no servicable observatories at the
Lagrange points because there are no spacecraft that can go out to
service them, and there are no spacecraft that can go out to service
them because there are no observatories that can be serviced.
Servicing something like WISE or SOHO doesn't make much sense, but
when we start talking about something like James Webb at
multiple-billion dollars, adding astronaut servicing starts to look at
least worth considering.

: They are just empty space. Manned mission to NEO sounds like one of
: big cost for limited return. And why would anyone want a mission where astronauts go through
: all the trouble and tedous transit to Mars, only not land there?

: Remote operation of rovers with only a second or two time delay.

I see absolutely no point whatsoever sending people to two-year mission merely
to act as remote rover operators.

Others do. And this could be tied-in with a Phobos or Deimos "lander".

: 90% or more of any deep space mission is propellant. Propellant is
: cheap (compared to hardware). If we can use cheap, modestly reliable
: rockets (90% reliablity instead of 99.5%... if we lose one now and
: then, who cares? its mostly just LOX)

But doesn't ISS etc use hypergolic fuels, not LOX?

Same concept. That's why we need to test it first. Two Centaurs or
ACES upper stages transferring propellant back and forth should to the
trick.

Brian

Brian Thorn wrote:
On Sun, 1 Nov 2009 12:49:46 +0000 (UTC), Yama
wrote:

: Augustine Commission pretty much recommends in its report what it calls
: "Flexible Path" - wide array of potential targets to be visited by manned
: spacecraft as a precursor to manned Mars mission. These include Near Earth Asteroids,
: moons of Mars, Lagrange points etc. It has got blogosphere all excited.

: I call it the "Build the Infrastructure Now, Decide Where To Go Later"

I just don't see where the savings are supposed to come.

Canceling Altair. Scaling-down Ares V (sized for Moon/Altair) to
existing ET diameter and 4- or 5-segment SRB (vs. 5 1/2 segment now
planned.) Cancel Ares I and move everything to this Ares V-Lite.

Big savings and a more robust launch system.

Quite the contrary,
all these proposed targets would need specialized craft and equipment to
design and build. A Phobos mission would be nearly as expensive and difficult for
Mars mission.

The simplest asteroid-rendezvous concepts simply call for two Orions
docked end-to-end. You don't really need a lander for a small
asteroid, its really just proximity operations due to the low gravity
(think NEAR's "landing".)

It seems to me that they were proposed because they SOUND easier.

And they defer the high-cost mission modules (landers, labs,
what-have-you) until later.

Not to mention that science return from asteroid mission is going to be
fraction what can be gained from Moon or Mars mission.

But potentially much more important if one is discovered on an impact
trajectory.

Except that current and projected Lagrange telescopes are not designed
to be serviceable...

Chicken meet Egg. There are no servicable observatories at the
Lagrange points because there are no spacecraft that can go out to
service them, and there are no spacecraft that can go out to service
them because there are no observatories that can be serviced.
Servicing something like WISE or SOHO doesn't make much sense, but
when we start talking about something like James Webb at
multiple-billion dollars, adding astronaut servicing starts to look at
least worth considering.

It's worth considering for future space telescopes of comparable cost to
JWST. It doesn't make sense for JWST itself because the design and fab
are too far along to retrofit it for human servicing.

JWST will carry a passive LIDS adapter "just in case" but the systems
are not designed for human servicing; a lot of improvisation would be
required.

Brian Thorn wrote:
: On Sun, 1 Nov 2009 12:49:46 +0000 (UTC), Yama
: wrote:
: I just don't see where the savings are supposed to come.

: Canceling Altair. Scaling-down Ares V (sized for Moon/Altair) to
: existing ET diameter and 4- or 5-segment SRB (vs. 5 1/2 segment now
: planned.) Cancel Ares I and move everything to this Ares V-Lite.

: Big savings and a more robust launch system.

Except you'd have to man-rate Ares V Lite, and still design all the
equipment you need for interplanetary travel. Only except that because
of launcher limitations, it is harder.

: Quite the contrary,
: all these proposed targets would need specialized craft and equipment to
: design and build. A Phobos mission would be nearly as expensive and difficult for
: Mars mission.

: The simplest asteroid-rendezvous concepts simply call for two Orions
: docked end-to-end. You don't really need a lander for a small
: asteroid, its really just proximity operations due to the low gravity
: (think NEAR's "landing".)

Even if this were practical (which I doubt), you'd still have to come up
with the larger craft for Mars mission, even if it's just Phobos or Mars Flyby.

: It seems to me that they were proposed because they SOUND easier.

: And they defer the high-cost mission modules (landers, labs,
: what-have-you) until later.

Given that the "high-cost mission modules" are the ones which make the whole
program meaningful in the first place, I again foresee no actual savings.
They will have to be developed at some point in any case.

: Not to mention that science return from asteroid mission is going to be
: fraction what can be gained from Moon or Mars mission.

: But potentially much more important if one is discovered on an impact
: trajectory.

So what's stopping sending a robotic mission to study one?

: Chicken meet Egg. There are no servicable observatories at the
: Lagrange points because there are no spacecraft that can go out to
: service them, and there are no spacecraft that can go out to service
: them because there are no observatories that can be serviced.
: Servicing something like WISE or SOHO doesn't make much sense, but
: when we start talking about something like James Webb at
: multiple-billion dollars, adding astronaut servicing starts to look at
: least worth considering.

Given the high costs involved, seems dubious. They could have built another
space telescope at the cost of HST service missions.

: : Remote operation of rovers with only a second or two time delay.
:
: I see absolutely no point whatsoever sending people to two-year mission merely
: to act as remote rover operators.

: Others do.

Who are these "others"? What is the precise value?

: : 90% or more of any deep space mission is propellant. Propellant is
: : cheap (compared to hardware). If we can use cheap, modestly reliable
: : rockets (90% reliablity instead of 99.5%... if we lose one now and
: : then, who cares? its mostly just LOX)
:
: But doesn't ISS etc use hypergolic fuels, not LOX?

: Same concept.

No, not really. It is much more complicated with cryogenics, which is why it hasn't
been done yet.

And really, again, the supposed "savings" seem to evaporate: now you have to
develope technology to store and transfer cryogenic fuels in the orbit,
and to test it with specialized missions.

On Wed, 4 Nov 2009 11:39:07 +0000 (UTC), Yama
wrote:

: Big savings and a more robust launch system.

Except you'd have to man-rate Ares V Lite, and still design all the
equipment you need for interplanetary travel. Only except that because
of launcher limitations, it is harder.

Man-rating is whatever NASA declares it to be, and they've already
recently lowered the requirements for EELV. Stick to as much
Shuttle-heritage hardware as possible (SSME, 4-segment SRB, ET
tankage) and you've gone a long, long way toward man-rating. And NASA
already wants Ares V to be "man-ratable", so we're probably going to
pay for it anyway, Ares I or not. So dump Ares I.

Two Ares V-Lites offer *more* payload than an Ares V and an Ares I,
and because both launchers are identical both pads can be the same,
simplifying ground handling and launch preparations. Dumping Ares I
for Ares V-Lite improves the situation, rather than limiting it.

Even if this were practical (which I doubt), you'd still have to come up
with the larger craft for Mars mission, even if it's just Phobos or Mars Flyby.

The craft, but not the lander/launcher. Getting down to the Mars
surface and launching again are going to be the monster costs of a
Mars mission. Flexible path does things incrementally, instead of
paying for everything in one fell swoop, which is the case if
President Obama announces "we're going to Mars by 2025!"

Given the high costs involved, seems dubious. They could have built another
space telescope at the cost of HST service missions.

Perhaps they could have, but probably wouldn't have. There was no
Einstein 2, no IRAS 2, no OAO-2. No NEAR-Shoemaker 2, no Magellan 2,
no Mars Global Surveyor 2. Instead, we got completely new successors
to them all. Internal and external politics generally forces NASA to
order a new 'bigger and better" satellite, which is much easier to
explain to Congress why you need it (versus "Another Hubble? Didn't we
just pay for that?") And that bigger and better means an all-new
design, which is invariably expensive. The only "bigger and better
than Hubble" we have seen so far is James Webb Space Telescope, now
approaching $4.5 billion. Shuttle missions range from $400 million
each for the early Hubble servicing missions to $900 million for the
last two or so. We updated Hubble with state-of-the-art instruments
about four times for less than the cost of JWST.

: I see absolutely no point whatsoever sending people to two-year mission merely
: to act as remote rover operators.

: Others do.

Who are these "others"?

The Augustine Commission, for one.

What is the precise value?

Operation of rovers in areas that have limited contact with Earth,
such as Valles Marineris.

: But doesn't ISS etc use hypergolic fuels, not LOX?

: Same concept.

No, not really. It is much more complicated with cryogenics, which is why it hasn't
been done yet.

Its more complicated, but potentially hugely rewarding. And it has
been tested to a degree, with NASA's SHOOT (Superfluid Helium On-Orbit
Transfer) aboard Shuttle mission STS-57. Small scale, but no
showstoppers.

ULA, which has tons of experience with cryogenic stages, doesn't seem
to think it will be that big a problem. They've already outlined one
concept, which uses a big folding sunshade to keep the cryo stage cool
during loitering/prop transfer.

And really. We're going to have to learn how to do that eventually.
We'll never explore the solar system if we have to take all the fuel
for the mission with us at one time from the launch pad.

And really, again, the supposed "savings" seem to evaporate: now you have to
develope technology to store and transfer cryogenic fuels in the orbit,
and to test it with specialized missions.

A couple of development missions (which could be used to launch
satellites or cargo to the Space Station as their primary objective)
eats up all the savings of full-scale development and, say ten years
of Ares V launches? I don't think so. And we just happen to have a
Space Station up there just waiting to take on an experiment like
that.

Brian

Yama wrote:
Augustine Commission pretty much recommends in its report what it calls
"Flexible Path" - wide array of potential targets to be visited by manned
spacecraft as a precursor to manned Mars mission. These include Near Earth Asteroids,
moons of Mars, Lagrange points etc. It has got blogosphere all excited.

Is there something I'm not getting there? Because quite frankly, that sounds like
biggest idiocy I've heard for long long time.

Bigger than Ares I, a technically flawed, fiscally irresponsible launch
vehicle which won't be flying for years duplicating nearly identically
the capabilities of a launch vehicle that has been flying for years now?

I mean, what there is in Lagrange points
for humans to do? They are just empty space. Manned mission to NEO sounds like one of
big cost for limited return. And why would anyone want a mission where astronauts go through
all the trouble and tedous transit to Mars, only not land there?

You are incapable and incompetent to land on Mars for another several
decades. You just can't recognize your incompetence :

http://www.apa.org/journals/features/psp7761121.pdf

Unskilled and Unaware of It: How Difficulties in Recognizing One's Own
Incompetence Lead to Inflated Self-Assessments

Another thing: Augustine Commission supports orbital refueling to get around launch
vehicle limitations. Is this really practical? Because it sure doesn't sound like it would be.

Progress and the ISS do it all the time.