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Old August 13th 10, 05:12 PM posted to sci.space.policy,alt.politics
William Mook[_2_]
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Default If You Could Cause Someone to Land on the Moon Tomorrow bySending NASA $5 Today, Would You Do it?

By 1969 America had spent $22 billion going to the moon. Another $18
billion would have taken us to Mars aboard a reusable Mars ship
supported at a space station on orbit by fully reusable space
shuttles. Reprovisioned with hydrogen fuel by improved Saturn V
rockets. (whose first stages are recovered to lower costs)

We would have departed for Mars aboard two ships on 12 Nov 1981 and
landed on the red planet in August 1982. The ships return via Venus
flyby on August 1983. The fleet is refurbished and flown again in Dec
1983, in 1986 and 1988. A 50 person permanent base would have been
established on Mars by 1989 and self sustaining colony established by
2000. The peak cost would have been $7 billion per year declining
after the peak. This amounts to 6 cents per person per day for every
American.

http://www.astronautix.com/craft/vonn1969.htm

1969. Von Braun's final vision for a manned expedition to Mars was a
robust plan that eliminated much of the risk of other scenarios. Two
ships would fly in convoy from earth orbit to Mars and back.

They were entirely reusable for future expeditions, the only element
being expendable being the Mars Excursion Module used to visit the
planet's surface. This was Von Braun's last attempt to convince the
American government to finance his dream. Five months later he would
be sidelined to a dead-end headquarters job at NASA, and leave the
Agency two years after that.

The successful landing on the moon of Apollo 11 brought a brief period
of political enthusiasm for manned spaceflight. A new Space Task Group
was formed to recommend a post-Apollo manned space program. On 4
August 1969 NASA Administrator Paine briefed the Space Task Group,
with Vice President Agnew chairing, on Marshall's proposed post-Apollo
integrated plan. Von Braun briefed the plan for a manned expedition to
Mars as a follow-on to Apollo. The Integrated Plan foresaw first
flight of a manned space shuttle by 1975, an earth orbit space station
soon thereafter, with production and improvement of the Saturn V
continuing, and the NERVA nuclear thermal upper stage completing
development. All of these projects would mean a Mars spacecraft like
that proposed by Boeing in 1969 could be developed, with the only new
unique hardware being the Mars Excursion Module (the Mission Module
would be one of the modules already proven on the earth orbit
station). Testing in earth orbit of the first Mars Excursion Module
would begin in 1978, with the first Mars landing coming in 1982.

Von Braun had tweaked his original Mars Expedition scenario between
1952 and 1956 to halve the size of his original Mars expedition
spacecraft. He used the same methods in 1969 to come up with Mars
spacecraft under half the mass of Boeing's 1968 IMIS. This allowed two
Mars expedition spacecraft to travel in convoy on the mission
together, providing Von Braun's preferred mutual support and back-up.
The Nuclear Shuttles used for propulsion were essentially the same as
Boeing's Primary Propulsion Modules, and had 38 metric tons less
propellant. But due to lower delta-V's at Mars orbit, only three of
the NERVA Primary Propulsion Modules (now called Nuclear Shuttles)
were needed per spacecraft as opposed to five in Boeing's study. The
spacecraft consists, from fore to aft:

* Two lateral PPM's. These were only partially fuelled, enough for
the necessary delta-V to set the spacecraft toward Mars on 12 November
1981. They then separated, and maneuvered back to rendezvous and
docking with the earth orbit station. There they were refueled and
reused for earth-moon shuttle service or a future Mars expedition.
* A central PPM. This provided all of the remaining delta-V for
the mission - insertion into Mars orbit, trans-Earth injection, and a
braking maneuver back into earth orbit at the end of the mission.
Significant savings were obtained by braking into and leaving a high-
altitude elliptical Mars orbit rather than a low-altitude circular
orbit.
* A Planetary Mission Module. This was the result of Phase B
studies to identify a module that could be used for both earth and
lunar space stations and interplanetary flights. It provided six crew
with quarters during the mission. It had sufficient consumables that
12 crew could be supported in case one of the spacecraft had to be
abandoned anywhere along the route.
* Mars Excursion Module. The variation for this mission had a mass
of 43 metric tons. It could descend from the high elliptical orbit,
and support three crew on the surface for up to sixty days. Since two
ships were in convoy, the two MEM's could land near each other and
provide mutual support. All six surface crew could return in one of
the MEM's ascent stages if needed.
* 16 unmanned probes. 12 would return samples from various sites
on the Martian surface to the orbiting PMM. Four would be dropped into
the atmosphere of Venus during the swingby of that planet on the
return home.

The mission profile was as follows:

* 12 November 1981: Trans-Mars injection. Each spacecraft had a
starting mass in low earth orbit of 727 metric tons. After the 3.8 m/s
maneuver, the two lateral PPM's would separate, leaving the single
PPM, PMM, MEM, and probes with a total mass of 614 metric tons.
* 9 August 1982: Mars orbit insertion. The spacecraft entered an
elliptical Mars orbit. This requires a delta-V of only 2.2 km/s, only
1/3 to 1/8 the amount Boeing assumed in their study for obtaining a
circular orbit. This was a huge driver in reducing the total
expedition mass. Mass before the maneuver was 295 metric tons, and
afterwards around 226 metric tons.
* The MEM's separate and headed for the surface. Meanwhile, the
three crew left aboard each PMM drop the 12 sample-return probes and
survey the Martian surface and moons from orbit.
* 28 October 1982: Trans-Earth Injection. Having shed the MEM and
probes, the mass at the start of the maneuver was 172 metric tons.
* 28 February 1983: Venus swingby. This reduces the velocity at
the return to earth, and provided an additional science opportunity.
Four probes were dropped into the atmosphere of Venus.
* 14 August 1983: Earth Orbit Insertion. The PPM fired one last
time to brake the spacecraft into low earth orbit. It docked with the
earth orbiting space station and the crews and their samples were
placed in quarantine. Final mass of each ship was 72.6 metric tons.
Von Braun preferred this approach to a direct return to earth in an
Apollo Command Module. His mission profile made the propellant
available for it, and the risk of contamination of the earth by
Martian organisms was eliminated.

The Mars spacecraft itself would refurbished via shuttle flights, two
additional PPM stages attached, the whole thing resupplied and
refueled, in readiness for further expeditions to Mars in 1983, 1986,
and 1988 - leading to a 50-person Mars base by 1989. With the
exception of the MEM, all of the spacecraft was reused. Von Braun
estimated this colonization of Mars within 20 years could be
accomplished with a peak NASA budget of $ 7 billion per year. This
robust, relatively safe plan was the culmination of 20 years of Mars
mission planning by the Peenemuende team and took full advantage of
the other space infrastructure elements in NASA's master plan. It
offered the possibility for Von Braun to witness his long-held dream
of a manned expedition to Mars in his lifetime.

The Space Task Group made its final report on 15 September 1969,
recommending the whole vast infrastructure envisioned by Von Braun. It
was not to be -- every element of the NASA plan, except for a much-
compromised space shuttle design, would be stripped away by Nixon's
budget office. There was no public support for such a grand scheme.
The view of Mars as a seemingly barren, lifeless, and uninteresting
world in any case was reinforced by the Mariner 7 mission which flew
by the planet the day after Von Braun's presentation was made. His
ultimate dream crushed, Von Braun was sidelined to a headquarters post
at NASA seven months later. He left NASA in 1972 and died in 1977.
Von Braun Mars Expedition - 1969 Mission Summary:

* Summary: Final NASA/Von Braun design for a manned expedition to
Mars using nuclear thermal rockets.
* Propulsion: Nuclear thermal
* Braking at Mars: propulsive
* Mission Type: opposition
* Venus swingby: yes
* Split or All-Up: all up
* ISRU: no ISRU
* Launch Year: 1981
* Crew: 12
* Mars Surface payload-metric tons: 5
* Outbound time-days: 270
* Mars Stay Time-days: 80
* Return Time-days: 290
* Total Mission Time-days: 640
* Total Payload Required in Low Earth Orbit-metric tons: 1452
* Total Propellant Required-metric tons: 1088
* Propellant Fraction: 0.74
* Mass per crew-metric tons: 121
* Launch Vehicle Payload to LEO-metric tons: 249
* Number of Launches Required to Assemble Payload in Low Earth
Orbit: 6
* Launch Vehicle: Saturn V-25(S)U

Gross mass: 726,000 kg (1,600,000 lb).
Unfuelled mass: 182,000 kg (401,000 lb).
Height: 82.00 m (269.00 ft).
Diameter: 10.06 m (33.00 ft).
Thrust: 1,733.80 kN (389,774 lbf).
Specific impulse: 850 s.