Multimillionaire's private space ship 'can land on Mars'

Rick Jones wrote:
Fred J. McCall wrote:
Rick Jones wrote:
David Spain wrote:
Pat Flannery wrote:
Lunar still has me going as to whether its a proper noun or not.
And how about Earth, not as a planet, but referring to soil?

I spent my first 18 years in agriculture. Does that mean my
education was 'well-grounded'?

No, and bringing that up will only muddy things...


Don't be a clod...

Time to put this discussion back in the hopper...


I agree, we aren't plowing any new ground here.

On 2011-04-22 03:21:43 -0500, jacob navia said:


It would be nice if all those multimillionaires would climb into
their spaceships and leave us alone for good.

I fully expect Musk will have to fly in his own contraption to prove it worthy.

And I'm sure they'll be pressure for him to preserve his control of the
companies and let someone else fly but I think it's damn near
impossible for him not to be in an early launch of a manned vehicle.

On Apr 21, 7:56*pm, wrote:
"In a statement released yesterday, Musk and SpaceX
also make the bold claim that the Dragon, once fitted
with modifications that the company is now developing
under NASA contract, would also be able to land "almost
anywhere on Earth or another planet with pinpoint
accuracy, overcoming the limitation of a winged
architecture that works only in Earth’s atmosphere"
(our emphasis)."

See:

http://www.theregister.co.uk/2011/04..._dragon_claim/

This has been known since the 1950s. How do you think ballistic
missile systems drop bombs on targets accurately? They use ballistic
re-entry vehicles that have a 1.5 L/D capable of terminal guidance.

http://en.wikipedia.org/wiki/Atmosph...entry_vehicles

We've also known since the 1940s, with vonBraun's Mars Projekt that
any system capable of landing on the Moon can also land on Mars and
return to Earth. The Falcon Heavy with cross-feeding, can lift 53
metric tons into LEO where it travels at 7.2 km/sec. To travel to the
Moon from LEO along a free-return trajectory requires the spacecraft
move at 10.85 km/sec. This means we must impart 3.65 km/sec to the
speed of the 53 ton spacecraft. Using hydrogen/oxygen with an exhaust
speed of 4.3 km/sec this propellant combination allows us to achieve
the desired velocity consuming only 57.2% of the 53 tons. That's 30.4
tons. Allowing 2.6 tons structure this leaves 20 tons useful load.

Landing softly on the moon requires a vehicle in a lunar free return
trajectory slow by 2.4 km/sec. Using the same rocket type used to
depart Earth to achieve this, requires 42.8% of the 20 tons useful
load be propellant. That's 8.6 tons of the total 20. Another 0.8
tons of structure leaves 10.6 tons of useful load on the moon.
Reusing the same 0.8 tons at take off, means that we must send 11.4
metric tons at launch, back along the same trajectory back to Earth.
This takes the same 2.4 km/sec and the same 42.8% of the 11.4 ton
total. This is another 4.9 metric tons of propellant, leaving 6.5
tons at burn out, of which 0.8 tons is structure, leaving 5.7 tons of
useful load.

So, we start with 53 tons in LEO and send 5.7 tons to the moon and
back, along with 0.8 tons of lunar landing structure, and 2.6 tons
around the moon. Both of which can be retrieved and reused.

For Mars, we require the 53 ton starting mass accelerate to a speed of
4.2 km/sec. This requires 62.4% of the starting mass be propellant.
A total of 33 tons. 2.6 tons structure. This leaves 17.4 tons of
useful load bound for Mars.

At Mars, we use aerobraking to slow down and land on Mars. So, we
have 17.4 tons useful load on Mars. Since we know water ice exists on
Mars, and since we know sunlight is available on Mars, and since we'll
be on Mars for sometime, and since we have used solar power to
maintain life support while in transit, then, we will use solar power
on Mars to break ice water down into hydrogen and oxygen, and recharge
our oxygen supplies, and breathe oxygen made on Mars while on Mars.

To get back to Earth from Mars surface requires the vehicle on Mars
accelerate 6.5 km/sec. This means using the same 4.3 km/sec rocket we
must carry 78.0% of the vehicle weight as propellant. Since we can
refuel on Mars while we wait for the planets to line up we can drop
down with our empty propellant tank that carries 33 metric tons of
propellant to get us off Earth. We also carry an additional 11.4
metric tons of propellant to use on Mars while we erect our gathering
system. In the end, we have our 53 metric tons on Mars prior to lift
off. 41.4 metric tons of the total is propellant. This leaves 11.6
remaining, of this 2.6 tons is structure. This leaves 9 metric tons
of useful payload.

3.3 tons more than we can take to the moon.

This excess, is the solar power system and long-duration life support.

On Apr 22, 10:10*pm, Robert Love wrote:
On 2011-04-22 03:21:43 -0500, jacob navia said:



It would be nice if all those multimillionaires would climb into
their spaceships and leave us alone for good.

I fully expect Musk will have to fly in his own contraption to prove it worthy.

And I'm sure they'll be pressure for him to preserve his control of the
companies and let someone else fly but I think it's damn near
impossible for him not to be in an early launch of a manned vehicle.

Heinlein wrote about this in his short story THE MAN WHO SOLD THE
MOON.

On Apr 22, 7:52*pm, Brian Thorn wrote:
On Thu, 21 Apr 2011 16:56:19 -0700 (PDT), wrote:
"In a statement released yesterday, Musk and SpaceX
also make the bold claim that the Dragon, once fitted
with modifications that the company is now developing
under NASA contract, would also be able to land "almost
anywhere on Earth or another planet with pinpoint
accuracy, overcoming the limitation of a winged
architecture that works only in Earth’s atmosphere"
(our emphasis)."

Cool talking points, but a useless capability. How will Dragon take
off again from another planet, does it have a Falcon 9 in its back
pocket? The landing part of a future space mission to the Moon or Mars
will be done by a different spacecraft, not the one that hauled the
crew from Earth up to the Transfer Spacecraft. NASA planned Altair to
be its next lunar lander, not Orion or HL-20.

Now if SpaceX wants to built a fully-reusable version of Altair, I'm
all ears.

Brian

Hydrogen Oxygen Propellant has an exhaust velocity of 4.3 km/sec
Lox Kerosene propellant has an exhaust velocity of 3.5 km/sec.

To get to Low Earth Orbit requires 9.1 km/sec speeds. To do this in
two stages means that you impart 4.55 km/sec to each stage. Using Lox
Kerosene means that each stage must be 73.5% propellant. If structure
is 7% of the total, this means that 80.5% is booster and 19.5% is
payload, for each stage. Compounding this by 2 stages means that
3.79% of the launch mass on Earth ends up in orbit.

So, with a 53 ton payload on orbit, we require 1,400 tons at lift
off.

To get to a trajectory to the moon requires 3.65 km/sec. Using
hydrogen oxygen a 53 ton starting mass requires 30 tons of
propellant.

To get a trajectory to to Mars requires 4.3 km/sec. Using hydrogen
oxygen a 53 ton starting mass requires 33 tons of propellant.

53 tons in Earth orbit require 30 tons of hydrogen oxygen propellant
to send it to the moon, and 33 tons to send it to Mars.

On mars the spacecraft uses aerobraking to slow down. On mars the
spacecraft refuels by using sunlight and water found on mars to refill
the hydrogen oxygen tanks.

A 53 ton mass on Mars requires 41.4 tons of propellant to get back to
Earth. This leaves 11.6 tons. Structure of 2.6 tons leave 9 tons
useful load for Mars.

The moon, being airless, requires rocket action to slow down, and
rocket action to take off.

This means that its best if the 20 tons separates into two stages, one
that flies past the moon and returns to Earth without any further
rocket action, and one that lands and takes off. So, this leaves a
2.6 metric ton section that carried the 30 tons originally at Earth
which separates leaving a 17.4 ton lunar stage. This stage requires
11.7 tons of propellant to land and take off from the moon. This
leaves 5.7 tons of useful load. Subtracting 0.7 tons of structure,
leave 5 tons of useful load. 4 tons less than can be carried to
Mars. This difference is the weight of the fuel processing facility
and the long duration life support facility.

By using CO2 + H2 to make CH4 + H2O using the Sabatier Process and
Mars atmosphere, it is possible to increase the density of propellant,
at a cost of reducing performance. The overall payload however, may
be improved, increasing total payload in the system. That's because
we have the potential of setting down over 17 tons on the Mars
surface, it would be nice if we could send it back to Earth as well,
and increase our capacity to carry payload from 9 tons to 12 tons by
increasing the mass carried in the tank that carried the 33 tons of
propellant initially allowing it to carry 50.5 metric tons of hydrogen/
methane mix.

Hydrogen/Methane with Oxygen propellant mix has an exhaust velocity of
3.95 km/sec.

http://www.grc.nasa.gov/WWW/Fuels-An...nts/GELLED.htm

To depart from LEO to Venus requires a speed of 3.9 km/sec be imparted
to the spacecraft. This requires 59.7% of the 53 ton starting mass be
propellant using hydrogen/oxygen. That's 31.6 metric tons. This
leaves 21.4 metric tons balance. Arriving at Venus we use aerobraking
to slow into an orbit around Venus (no landing) From here we can
examine Venus from above. To return to Earth requires an added speed
of 3.5 km/sec. This requires 55.7% of the 21.4 tons be propellant
using hydrogen/oxygen. That's 12.0 tons. Thus, 9.4 tons can be sent
to a mission to orbit Venus - with no landing.

Even so, probes can be dropped into the Venusian atmosphere that has a
telerobotic capability. This in combination with microwave imagery
and other remote sensing technologies, can provide a quite satisfying
exploration.

On Apr 24, 12:43*pm, William Mook wrote:
On Apr 21, 7:56*pm, wrote:

"In a statement released yesterday, Musk and SpaceX
also make the bold claim that the Dragon, once fitted
with modifications that the company is now developing
under NASA contract, would also be able to land "almost
anywhere on Earth or another planet with pinpoint
accuracy, overcoming the limitation of a winged
architecture that works only in Earth’s atmosphere"
(our emphasis)."

See:

http://www.theregister.co.uk/2011/04..._dragon_claim/

This has been known since the 1950s. *How do you think ballistic
missile systems drop bombs on targets accurately? *They use ballistic
re-entry vehicles that have a 1.5 L/D capable of terminal guidance.

http://en.wikipedia.org/wiki/Atmosph...entry_vehicles

We've also known since the 1940s, with vonBraun's Mars Projekt that
any system capable of landing on the Moon can also land on Mars and
return to Earth. *The Falcon Heavy with cross-feeding, can lift 53
metric tons into LEO where it travels at 7.2 km/sec. *To travel to the
Moon from LEO along a free-return trajectory requires the spacecraft
move at 10.85 km/sec. *This means we must impart 3.65 km/sec to the
speed of the 53 ton spacecraft. *Using hydrogen/oxygen with an exhaust
speed of 4.3 km/sec this propellant combination allows us to achieve
the desired velocity consuming only 57.2% of the 53 tons. *That's 30.4
tons. *Allowing 2.6 tons structure this leaves 20 tons useful load.

Landing softly on the moon requires a vehicle in a lunar free return
trajectory slow by 2.4 km/sec. *Using the same rocket type used to
depart Earth to achieve this, requires 42.8% of the 20 tons useful
load be propellant. *That's 8.6 tons of the total 20. *Another 0.8
tons of structure leaves 10.6 tons of useful load on the moon.
Reusing the same 0.8 tons at take off, means that we must send 11.4
metric tons at launch, back along the same trajectory back to Earth.
This takes the same 2.4 km/sec and the same 42.8% of the 11.4 ton
total. *This is another 4.9 metric tons of propellant, leaving 6.5
tons at burn out, of which 0.8 tons is structure, leaving 5.7 tons of
useful load.

So, we start with 53 tons in LEO and send 5.7 tons to the moon and
back, along with 0.8 tons of lunar landing structure, and 2.6 tons
around the moon. *Both of which can be retrieved and reused.

For Mars, we require the 53 ton starting mass accelerate to a speed of
4.2 km/sec. *This requires 62.4% of the starting mass be propellant.
A total of 33 tons. *2.6 tons structure. *This leaves 17.4 tons of
useful load bound for Mars.

At Mars, we use aerobraking to slow down and land on Mars. * So, we
have 17.4 tons useful load on Mars. *Since we know water ice exists on
Mars, and since we know sunlight is available on Mars, and since we'll
be on Mars for sometime, and since we have used solar power to
maintain life support while in transit, then, we will use solar power
on Mars to break ice water down into hydrogen and oxygen, and recharge
our oxygen supplies, and breathe oxygen made on Mars while on Mars.

To get back to Earth from Mars surface requires the vehicle on Mars
accelerate 6.5 km/sec. *This means using the same 4.3 km/sec rocket we
must carry 78.0% of the vehicle weight as propellant. *Since we can
refuel on Mars while we wait for the planets to line up we can drop
down with our empty propellant tank that carries 33 metric tons of
propellant to get us off Earth. *We also carry an additional 11.4
metric tons of propellant to use on Mars while we erect our gathering
system. *In the end, we have our 53 metric tons on Mars prior to lift
off. 41.4 metric tons of the total is propellant. *This leaves 11.6
remaining, of this 2.6 tons is structure. *This leaves 9 metric tons
of useful payload.

3.3 tons more than we can take to the moon.

This excess, is the solar power system and long-duration life support.

btw; there's a few variables like orbital motions of planets and
moons, and the fact of having to haul a considerable amount of
shielding that's going to be mostly inert mass or at least spare water
that'll be replaced with human poop for your radiation shielding, and
you'll need to pack along lots of energy because even the to/from trip
will always be near cryogenic according to your specifications (no
problems getting rid of heat, just big-time problems holding onto
heat).

Must be why raw/naked ice doesn't melt in space?

A sizable plutonium fueled heater and electrical energy generator
should come in real handy for this trillion plus dollar mission to/
from Mars.

http://translate.google.com/#
Brad Guth, Brad_Guth, Brad.Guth, BradGuth, BG / “Guth Usenet”

In sci.space.policy message
, Fri, 22 Apr 2011 18:52:23, Brian Thorn
posted:

On Thu, 21 Apr 2011 16:56:19 -0700 (PDT), wrote:

"In a statement released yesterday, Musk and SpaceX
also make the bold claim that the Dragon, once fitted
with modifications that the company is now developing
under NASA contract, would also be able to land "almost
anywhere on Earth or another planet with pinpoint
accuracy, overcoming the limitation of a winged
architecture that works only in Earth’s atmosphere"
(our emphasis)."

Cool talking points, but a useless capability. How will Dragon take
off again from another planet, does it have a Falcon 9 in its back
pocket?

It has already been demonstrated that Dragon does not need a crew.

A Falcon Heavy, to judge from the figures, can launch enough mass to
Mars to allow delivery of a fully-loaded re-enter-mode Dragon into the
Martian atmosphere. It could carry, with revised hatch arrangements, a
few Robonaut /n/ and a vehicle. At anything like suggested prices, that
should be competitive with what NASA would otherwise hope to spend.

But I think he's optimistic about "any" planet.

Mercury : parachutes no good
Venus : parachutes, etc., melt - or dissolve
Earth ; OK
Mars : OK?
Jupiter, Saturn, Uranus, Neptune : nothing to land on
Pluto : demoted

--
(c) John Stockton, nr London, UK. Turnpike v6.05.
Website http://www.merlyn.demon.co.uk/ - w. FAQish topics, links, acronyms
PAS EXE etc. : http://www.merlyn.demon.co.uk/programs/ - see in 00index.htm
Dates - miscdate.htm estrdate.htm js-dates.htm pas-time.htm critdate.htm etc.

A 100 megawatt solar power system, using a ultra-light-weight
concentrators can power an ion rocket capable of generating 400 kg
force with an exhaust velocity of 50 km/sec. This system, including
collector, masses 7 metric tons. Its a 1% model of the 10 GW system
I've spoken of previously.

As part of a 53 metric ton payload at LEO, of which 6 metric tons is
ion propellant, the solar powered ion stage imparts 6 km/sec to the
remaining 40 tons of useful load.

This is enough to take the 40 tons to an orbit around Mercury.

To land on Mercury from low orbit takes 3.0 km/sec. To take off the
same. With a 4.3 km/sec chemical rocket lander -adapted from the moon
landing - 75.3% of the total mass starting in orbit must be
propellant, leaving 24.7% returned to orbit. With a 7.7% structure
fraction this leaves 17.0% useful load. Starting with 22 tons we have
3.7 tons of useful load on Mercury of this 2 tons is structure and 1.7
tons is payload.

A total of 18 tons remain on orbit. 3.5 tons of that is propellant to
return to Earth. 7.5 is long term life support for the mission.

This stage produces 2.5 tons of thrust at Mercury due to increased
solar intensity. The collector also operates as a solar shield to the
orbiting module.

The ion engine may also be used to increase the payloads sent to Venus
and Mars, and even explore the asteroids with the same sort of capsule
used in all these other missions.

Using the 100 MW (at Earth) 200 MW (at Venus) or 660 MW (at Mercury)
power plant, equipped with laser beam to power a laser propulsion
powered lander, improved capacities are possible. A Venus landing and
return of material to orbit using first an unpiloted probe. 5.8
metric tons of force may be generated by a rocket operating this way
at Venus with a 7 km/sec exhaust velocity. A 19.2 metric ton force
may be generated by a similar rocket operating at Mercurcy. 34.4
metric tons force may be exerted by a rocket operating at half the
exhaust velocity (3.5 km/sec) at Mercury. With 0.4 gravity, most of
the payload arriving at Mercury, save the 7 ton solar power portion,
can be landed on the planet by careful development of this technique.

A large inflatable structure may be deorbited. Deorbiting a free
floating landing platform that remains 50 km above the surface of
Venus reproduces Earth normal pressures at low temperatures which are
more easily sustained than surface conditions.

Then, using a laser propulsion system to land a piloted vehicle on the
platform and return it to the orbiting module would be tried after a
teleoperated robot were placed and returned. This would test the
technology needed for future Venus bases.

At 1 atm pressure the atmosphere of Venus is 3x heavier than the
atmosphere of Earth. So, a 500 m diameter torus that has a 10 meter
diameter tube (the same one used to tension the solar concentrator)
has a 296 ton lifting capacity when the torus is filled with Earth air
at 1 atm - carrying 130 tons of oxygen and nitrogen. This is
scavenged from the Venusian atmosphere once the unit is placed in the
atmosphere. At 1/10th atm lift is only 30 tons, and only 13 tons of
gas is used to inflate the system. Increasing pressure as desired
gases are harvested from the Venusian atmosphere, lowers altitude.

Placing a tensioned sheet within the torus interior allows the 480 m
sheet to be used as a landing platform. It can also receive power
beamed to it from the orbiting module as long as both are visible to
one another. A molniya type orbit combined with a location of a
station near the pole under the apoveneral location of the module's
orbit, allows nearly continuous power separated by brief periods of
interruption. This method of gathering power reduces the total area
of solar collection. The receiver doubles as a solar panel for low
energy operations for periods of time when the orbiting module is
unavailable. A total of 15,393 sq meters of interior area is
available within this torus.

This same system can be adapted for basing schemes on the surface of
the Moon, Mercury, Ceres, and Mars, or for free flying stations in
space.

http://upload.wikimedia.org/wikipedi...2003-00106.jpg

Basically a 3.5 ton structure combined with 33 tons of propellant, and
16.5 tons of other materials, can take you to the moon's surface, to
mars surface, to mars orbit, to diemos, to phobos, to orbit around
venus.

Adding 500 meter diameter, 100 MW solar concentrator - with ion rocket
engine - massing 7 tons - allows taking this show to Mercury and the
Asteroid belt.

Adding a power beaming and laser rocket capability, allows returning
samples from Venus surface, and increasing the amounts of payload to
and from Mercury.

Adapting the torus used to concentrate sunlight in the solar ion
rocket we can create bases floating on Venus, as well as orbiting
stations, and landed based on Mercurcy, Mars, Diemos, Phobos, Moon,
Ceres, and other asteroids.

Each launch is at present $125 million.
Each vehicle at $20 million per ton is $70 million.
The power plant is $140 million.
Propellant, payroll and consumables are nil on this scale.
Scientific and other gear is $3 million per ton - these add up to less
than $30 million per flight.

So, at $250 million - each planetary flight would cost less than half
a space shuttle launch.

With 5 people per flight - each paying $50 million - would cost about
the same as present day Soyuz flights.

This is all well within the budgets and capabilities of Space X to
achieve.

Here are the Synodic periods

Mercury 0.317
Venus 1.599
Mars 2.135
Vesta 1.380
Ceres 1.278
Hygeia 1.219

So, in a year there will be several opportunities to travel around the
inner solar system, as well as to the moon and the Lagrange points in
Cislunar space.

20 flights per year at $0.25 billion is $5.0 billion per year, about
1/4 the cost of NASA at present.