If we do return to the Moon

what do we need to do before we send men back ?

A couple of things I came up with a

An orbiter to map the Moon in detail especially the poles. Many areas of the
Moon today are not mapped to 20 m resolution we can easily do 10m for the
entire moon and 1-2m for selected portions.

A follow on to Prospector getting a better idea of where the hydrogen is.

A radar map to give us a picture at depth of the Moons surface.

A couple of landers at potential base sites would be usefull.

What did I miss in my quick list?

"Dholmes" wrote in message .. .
what do we need to do before we send men back ?

A couple of things I came up with a

An orbiter to map the Moon in detail especially the poles. Many areas of the
Moon today are not mapped to 20 m resolution we can easily do 10m for the
entire moon and 1-2m for selected portions.

A follow on to Prospector getting a better idea of where the hydrogen is.

A radar map to give us a picture at depth of the Moons surface.

A couple of landers at potential base sites would be usefull.

What did I miss in my quick list?

Development of:
- Solar Electric tug to transport cargo from LEO to Lunar Orbit
- Lunar chemistry kit, to extract Oxygen from lunar soils
- Construction techniques appropriate to lunar conditions, e.g cut and
cover
- Edible plants that can grow in a lunar cycle
- Cheap and easy (not neccessarily efficient) solar cells that can be
manufactured on the moon or in space.
- Virtual Reality controlled robots for work on the lunar surface,
controlled in doors or even from Earth.
- Remote controlled digging machines that can collect ores from the
lunar surface

"Alex Terrell" wrote in message
om...
"Dholmes" wrote in message
.. .
what do we need to do before we send men back ?

A couple of things I came up with a

An orbiter to map the Moon in detail especially the poles. Many areas of
the
Moon today are not mapped to 20 m resolution we can easily do 10m for
the
entire moon and 1-2m for selected portions.

A follow on to Prospector getting a better idea of where the hydrogen
is.

A radar map to give us a picture at depth of the Moons surface.

A couple of landers at potential base sites would be usefull.

What did I miss in my quick list?

Development of:
- Solar Electric tug to transport cargo from LEO to Lunar Orbit

This seems more of a long term goal not prereturn. Personally I prefer Solar
thermal.

- Lunar chemistry kit, to extract Oxygen from lunar soils
- Construction techniques appropriate to lunar conditions, e.g cut and
cover

Both very useful.


- Edible plants that can grow in a lunar cycle

I really do not see a need for this artificial lighting can easily
supplement real light or even replace it.

- Cheap and easy (not neccessarily efficient) solar cells that can be
manufactured on the moon or in space.

Again very useful longterm but seems more of a later item.

- Virtual Reality controlled robots for work on the lunar surface,
controlled in doors or even from Earth.
- Remote controlled digging machines that can collect ores from the
lunar surface

Both useful a simple brick making device may be useful as well.

Dholmes wrote:

I really do not see a need for this artificial lighting can easily
supplement real light or even replace it.

There is no way you can grow plants for any practical purpose (e.g. food)
with artificial light. To grow 1 acre (10000 m²) you would need 14 MW
power - which means at least a nuclear fission reactor, which Greenpeace
would never allow to be launched from Earth.

It is perhaps more than anything else the question of growing plants that
make Mars a much more favorable destination than the Moon, because of its 24
hour day.

--
Steen Eiler Jørgensen
"Time has resumed its shape. All is as it was before.
Many such journeys are possible. Let me be your gateway."

"Steen Eiler Jørgensen" wrote in message
. ..
Dholmes wrote:

I really do not see a need for this artificial lighting can easily
supplement real light or even replace it.

There is no way you can grow plants for any practical purpose (e.g. food)
with artificial light. To grow 1 acre (10000 m²) you would need 14 MW
power - which means at least a nuclear fission reactor, which Greenpeace
would never allow to be launched from Earth.

Last time I checked with hydroponics it took to grow the vast majority of
the required food less then 10 kw per person .
So 14 MW supplemented with some real light plus a little meat and luxuries
from Earth would support 2000+ people.
I do not see a Lunar base approaching 2000 people for a long time.


It is perhaps more than anything else the question of growing plants that
make Mars a much more favorable destination than the Moon, because of its
24
hour day.

For a colony I would agree but for a base I do not.

Last time I checked with hydroponics it took to grow the vast majority of
the required food less then 10 kw per person .
So 14 MW supplemented with some real light plus a little meat and luxuries
from Earth would support 2000+ people.
I do not see a Lunar base approaching 2000 people for a long time.

I heard they grow canabis plants under grow lights in Canada, so they can't be
spotted from the air. If it can be done on the Earth, it can be done on the
Moon.

Tom

Dholmes wrote:


There is no way you can grow plants for any practical purpose (e.g. food)
with artificial light. To grow 1 acre (10000 m²) you would need 14 MW
power - which means at least a nuclear fission reactor, which Greenpeace
would never allow to be launched from Earth.


Last time I checked with hydroponics it took to grow the vast majority of
the required food less then 10 kw per person .

Yeah, his figures are off by a factor or three. People grow huge farms of
illegal drugs inside their houses with heatlamps and hydroponics.

JRS: In article , seen in
news:sci.space.policy, Steen Eiler Jørgensen
posted at Sun, 16 Nov 2003 14:29:58 :-

There is no way you can grow plants for any practical purpose (e.g. food)
with artificial light. To grow 1 acre (10000 m²) you would need 14 MW
power - which means at least a nuclear fission reactor, which Greenpeace
would never allow to be launched from Earth.

10000m^2 is a hectare, not an acre, which is 4840 square yards; 1 ha =
2.471 acres. Stick to SI units; let those who only understand Imperial
units make their own mistakes. Granted, Danish acres might be bigger
than ours.

You can halve that power, since plants are used to night and day; and
reduce it further, to allow for angle-of-incidence and for clouds.

You can halve it again, if power can be stored until night and the
plants can use real sunlight or light from solar power during the lit
fortnight.

--
© John Stockton, Surrey, UK. / ©
Web URL:http://www.merlyn.demon.co.uk/ - FAQish topics, acronyms, & links.
Correct = 4-line sig. separator as above, a line precisely "-- " (SoRFC1036)
Do not Mail News to me. Before a reply, quote with "" or " " (SoRFC1036)

Dr John Stockton wrote:

10000m^2 is a hectare, not an acre, which is 4840 square yards; 1 ha =
2.471 acres. Stick to SI units; let those who only understand
Imperial units make their own mistakes. Granted, Danish acres might
be bigger than ours.

Oops. I'm sorry - my mistake. I thought 'acre' was english for 'hektar'.
Thanks for clearing this up. And no - Danish acres aren't bigger than yours
;-)

You can halve that power, since plants are used to night and day; and
reduce it further, to allow for angle-of-incidence and for clouds.

Well, true.

You can halve it again, if power can be stored until night and the
plants can use real sunlight or light from solar power during the lit
fortnight.

Well, in principle, you're right. *If* you can store that much energy
without much loss for 14 days, *then* it's not an energy issue any longer.
But still, technically, t's just a lot easier on Mars

--
Steen Eiler Jørgensen
"Time has resumed its shape. All is as it was before.
Many such journeys are possible. Let me be your gateway."

Dholmes wrote:

What did I miss in my quick list?

Development of a communications relay satellite in a halo orbit around the
L2 Lagrange point in the Earth-Moon-system, providing a communications link
to the far side of the Moon.

From http://www.tsgc.utexas.edu/archive/design/farside.html

"During the construction phase, a satellite in an L2 halo orbit will relay
data from the lunar surface to a geostationary satellite in Earth orbit to
the Earth's surface. When the base becomes fully operational, however, a
radio-free sky is desired to take accurate astronomical readings. Therefore,
a fiber optic cable will be used as a communication link from the base to a
transmitter/receiver station on the near side of the Moon. It will be laid
out by a robotic rover from the base to the limb of the Moon. From there,
the signal can be broadcasted directly to Earth without interfering with
astronomical observations."

From http://www.tsgc.utexas.edu/archive/design/farside2.html

"To provide constant communication with the lunar nearside base as well as
Earth, a communication system was devised where the relaying point is a
satellite in a halo orbit about the L2 unstable libration point. This would
permit full coverage of the lunar farside and the constant monitoring of the
construction activities being conducted. Since L2 is an unstable libration
point, stationkeeping burns totaling 93.3 fps/yr and period control burns
totaling 240 fps/yr will have to be conducted in order to maintain the
orbit. After three years, the satellite at L2 will be refueled and moved to
the stable libration point L5, where it will remain throughout the lifetime
of the observatory."

From http://adsabs.harvard.edu/cgi-bin/np...TIN...9512644B

"Project ECHO: Electronic Communications from Halo Orbit - Abstract: The
design of a communications relay to provide constant access between the
Earth and the far side of the Moon is presented. Placement of the relay in a
halo orbit about the L2 Earth-Moon Lagrange point allows the satellite to
maintain constant simultaneous communication between Earth and scientific
payloads on the far side of the Moon. The requirements of NASA's
Discovery-class missions adopted and modified for this design a total
project cost should not exceed $150 million excluding launch costs, launch
must be provided by Delta-class vehicle, and the satellite should maintain
an operational lifetime of 10 to 15 years. The spacecraft will follow a
transfer trajectory to the L2 point, after launch by a Delta II 7925 vehicle
in 1999. Low-level thrust is used for injection into a stationkeeping-free
halo orbit once the spacecraft reaches the L2 point. The shape of this halo
orbit is highly elliptical with the maximum excursion from the L2 point
being 35000 km. A spun section and despun section connected through a
bearing and power transfer assembly (BAPTA) compose the structure of the
spacecraft. Communications equipment is placed on the despun section to
provide for a stationary dual parabolic offset-feed array antenna system.
The dual system is necessary to provide communications coverage during
portions of maximum excursion on the halo orbit. Transmissions to the NASA
Deep Space Network 34 m antenna include six channels (color video, two
voice, scientific data from lunar payloads, satellite housekeeping and
telemetry and uplinked commands) using the S- and X-bands. Four radioisotope
thermoelectric generators (RTG's) provide a total of 1360 W to power onboard
systems and any two of the four Hughes 13 cm ion thrusters at once. Output
of the ion thrusters is approximately 17.8 mN each with xenon as the
propellant. Presence of torques generated by solar pressure on the antenna
dish require the addition of a 'skirt' extending from the spun section of
the satellite for balance. Total mass of the satellite is approximately 900
kg at a cost of $130 million FY99."

I wasn't able to find a suitable illustration on the web, so I scanned an
illustration (it's a very rough sketch!) from a book I have ("Voyage through
the Universe - Spacefarers", Time-Life Books 1989, Danish ed., pp. 58-59):
http://www.dsri.dk/~sej/pics/lunar_halo_orbit.jpg

--
Steen Eiler Jørgensen
"Time has resumed its shape. All is as it was before.
Many such journeys are possible. Let me be your gateway."