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Subject: SPACE Digest V11 #109

SPACE Digest                                     Volume 11 : Issue 109

Today's Topics:
             space news from Jan 22 AW&ST
             Re: Power Economics and SPS
Astronomical telescopes for NASA spacecraft arrive at Goddard (Forwarded)
           Feynman (was fun space fact #1)
----------------------------------------------------------------------

Date: 3 Mar 90 08:20:09 GMT
From: wuarchive!cs.utexas.edu!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: space news from Jan 22 AW&ST

Marginally space-related:  this week's cover story is the SR-71 retirement,
with assorted photos I've never seen before.  [My conjecture is that AW&ST
decided "well, if they're retiring the things, they probably won't object
to us publishing the photos we've been sitting on for years...".]

NASA briefly reconsiders use of the shuttle to launch Mars Observer in
1992, as Commercial Titan is very expensive, but discards the idea after
figuring in the costs of astronaut training etc. to mount a shuttle
mission for it.

Payload for the Feb. 16 Atlantis mission [yes, the one that's up now]
is a combination spysat and snoopsat, with both digital imaging gear
and communications-eavesdropping receivers.  Launch will be at 0121 EST
if it goes up on the 16th.  [I'm curious -- is this consistent with the
actual launch time this week?  I haven't kept track.]

White House orders NASA to get more input from outside sources, notably
industry and the science community, on plans for the Moon and Mars.  The
White House, uh, *noticed* Lawrence Livermore's proposal to do a good
fraction of NASA's plans at 1/40th of the price.  Quayle says "We need
to consider innovative ways of doing business... [past plans] may be
bound by restrictions and policy which, while well intentioned, bow
more to tradition than ingenuity".

NASA picks 23 new astronauts, including USAF Major Eileen M. Collins
(a student at the USAF Test Pilot School at Edwards), the first female
pilot astronaut.

Pictures of the LDEF retrieval.  Columbia's crew photographed LDEF
extensively (800-odd shots) to document its in-space state as thoroughly
as possible, partly due to concerns about experiments disintegrating
when exposed to air and gravity during return.  [In fact, there wasn't
much debris in the payload bay afterward, most things stood up well.]
Columbia then maneuvered to fly belly-first, using the orbiter as a
wake shield to minimize further space effects on LDEF.

One minor incident occurred late in the mission, when radio interference
slightly scrambled a state-vector update command sent up from the ground,
and Columbia began rotating slowly (peak rate about 0.5 RPM).  The crew
was asleep at the time, but mission control woke them up and they sorted
it out.

Columbia retrofire will be a long firing well out-of-plane, to burn off
a couple of tons of fuel and help set up the proper center of gravity
for landing.

Superbird B prepared for shipment to Kourou after last-minute amplifier
problems fixed.

Feature article on Lawrence Livermore's "Great Exploration" proposal,
doing Moon and Mars bases by the year 2000 for total cost of about $10G
(compared to NASA's 25 years and $400G).  It's caught the eye of a lot
of people; NASA's response has been very negative.  The primary authors
are Lowell Wood, Rod Hyde, and Yuki Ishikawa.

The G.E. proposal is explicitly a minimal scheme, not an "absolutely first
class" [translation: gold-plated] one like NASA's.  Major points of note:

    - Reliance on existing technology.  "The thing we plan to do
    use existing technology in forms and integrations that can be
    demonstrated on Earth in 2-3 years at a cost of $50-150M."
    No new launchers:  hardware goes up on Titan 4s and Deltas,
    people on the shuttle or in Apollo-type capsules, with use
    of commercial launchers a possibility.  24 launches in 10 years.

    - Risks comparable to those accepted during Apollo, rather than
    the rather lower levels NASA prefers now.  However, there are
    provisions for emergency crew return at all times.

    - Less early science.  "The crew will all be trained scientists
    and engineers who will do science the way Charles Darwin did it
    during the voyage of HMS Beagle.  Darwin was the only scientist
    aboard and his scientific work was ancillary to his other duties
    as part of the crew."  For example, there is no major observatory
    as part of the lunar plans.  Later science work would build on
    the GE infrastructure.

    - No unnecessary auxiliaries.  Specifically, none of the numerous
    unmanned precursor missions (mapping and communications satellites,
    probes, and sample-return missions) that are bundled into NASA's
    plans.

    - Standardized inflatable modules forming an Earth-orbit space
    station and the lunar and Martian bases.  Using current space-suit
    technology, inflatable Kevlar modules weigh one-tenth of what
    rigid structures do and can be packed much more efficiently at
    launch.  The basic hardware for the space station, the Moon base,
    and the Mars base is *one* Titan 4 launch each.  Modules would
    be 5m in diameter by 15m long, with double outer walls, metal
    end plates, and a multi-layer outer shield to provide insulation
    and meteorite protection.  Seven modules, at under a ton each,
    would be joined around a central hub for the space station.
    The lunar base would be another seven; the Mars base would be four.
    They would be inflated at the destination, after which astronauts
    would enter and (in shirt sleeves, not spacesuits) put together
    the interior furnishings.  Interior components would be modular
    and prefabricated, assembled and tested on Earth beforehand.

NASA, um, has doubts.  It questions the feasibility of the inflatable
structures, but Wood replies that (a) NASA's own spacesuit contractors
say the modules are practical, and (b) NASA's own lunar-base plan
includes an inflatable dome 11m in diameter.  Wood says that in general,
all the GE technology is from NASA research or NASA-sponsored industrial
research.  NASA says having the astronauts assemble the internal hardware
is "a huge flaw", but Wood says it is no more difficult than prefabricated
home construction on Earth, and saves vast amounts of weight (the weight
advantage is a factor of 2-3 even after furnishing).  NASA says the
cost estimates are wildly optimistic and omit important expenses.

The basic GE plan, if started immediately, would test components for
the space station and orbital fuel dump immediately and launch them
in mid-1991.  Design and procurement of lunar-mission hardware would
start while water was being launched to the fuel dump, to be converted
to liquid hydrogen and liquid oxygen and stored for the lunar mission.

The lunar hardware would go up in mid-1994 and go to the Moon later
that year, using a lunar transfer vehicle powered by RL-10 engines
and fueled in orbit.  Lunar equipment would include a rocket-powered
"hopper", two lunar tractors, an emergency-return module, a greenhouse
module, and enough food, water, and air to support four people for
ten years in a "spartan" lifestyle.  Once modules were inflated and
assembled, a small "snow blower" would be used to cover them with
lunar soil as protection against radiation and meteorites.  A "soil
roaster" to extract oxygen from lunar soil for use as fuel is an
option, possible with an extra launch but not essential to the main
program.

The Mars mission hardware would go up in fall 1996, and would likewise
be fueled in orbit, to leave early 1997.  Two vehicles would go, one
to be used for surface descent, the other a return vehicle to be left
in orbit.  Surface equipment would include a plant to extract oxygen
from the carbon-dioxide atmosphere, an ascent module, scientific
instruments, rovers, a hopper, and life support for a 400-day stay.
Return would be in late 1999, with at least 1000lbs of samples.
Part of the crew could stay on Mars, and more missions would follow.
--
MSDOS, abbrev:  Maybe SomeDay |     Henry Spencer at U of Toronto Zoology
an Operating System.          | uunet!attcan!utzoo!henry [e-mail]

------------------------------

Date: 3 Mar 90 21:15:29 GMT
From: mailrus!b-tech!kitenet![e-mail]  (Russ Cage)
Subject: Re: Power Economics and SPS

In article <[e-mail]> [e-mail] (Paul Dietz) writes:
>In article <[e-mail]> [e-mail] (Mike Van Pelt) writes:
>>The cost of any system with a high startup capital cost is extremely
>>sensitive to delays.  Which is why nobody is going to make that
>>investment, knowing full well that All The Usual People will clog the
>>courts with lawsuits, injunctions, etc [....]

Mike:  That only applies if the USA is the primary market for such
power.  It pays off the same except in local acid-rain reduction
if the buyer is in another country.  SPS by nature addresses a
global market.  Other countries, notably France and Japan, have
few to no problems with legal bottlenecks.

And on to what is, IMHO, an overly-quick dismissal of SPS by Paul Dietz:

>  Consider the technologies that would have to be developed:
>  (a) the ability to house thousands of workers in space,

We've done several at a time, so have the Soviets.  Furnishing
a pressure vessel is not very hard, we just need bigger ones.
(Dunno about thousands of workers, we may only need hundreds.)

>  (b) much cheaper transportation to LEO and beyond,

That is nice, but not essential according to what I remember.
For one thing, the first returns from the lunar processing
operations include oxygen, both for breathing and rocket fuel.
This cuts required transport tonnage drastically.  If you have
a reference which states otherwise, pointer is requested.

>  (c) automated SPS construction equipment that can operate in space,

Er, what for?  This would eliminate the "thousands of workers", right?
Some jobs will be highly automated, like vacuum-depositing thousands
of m^2 of PV cells at a time, but that's easy in space.

>  (d) automated mining equipment that can [mine the moon or an asteroid],

I saw a neat concept for a lunar dragline, which could scoop up dirt
and deposit it near the mine head.  It would take 3 towers, 3 winches,
some cables and a scoop-bucket.  You could run it with an IBM-PC and
little human oversight.  This is *one* concept, of many possibilities.
We are talking about grabbing anything in sight rather than being
selective miners, so dumb solutions will work as well as smart ones.
We could build and test this one for peanuts.  Just need a few $.
The dragline will also work for shielding lunar habitations, so it
does multiple duty.

>  (e) equipment ... or launch millions of tons of material off the moon,

SSI's mass-driver appears ready to do just that.  They're up to 1500 G's.
That's 0 to lunar escape velocity in < 200 meters.  Doing it in 1 km
only takes 300 G's.  Launching 1 million tonnes/year, assuming 40% duty
cycle, is about 80 kg/sec.  One good conveyor belt will carry that.  Power
demand to launch it is about 320 MWe at 40% duty cycle & 70% efficiency
(assuming solar power for the catapult; a nuke plant could run at night
and use a higher duty cycle and lower power).  We can do that.

>  (f) orbital smelting and refining.

Many refining reactions have been done in the lab.  (Unfortunately,
I can't find my copy of D.T. Lin's study of preparation of lunar
basalt to make alumina cement by heating; considering that the
efflux from the heating step includes the iron...)  We can test
the refining equipment on earth, since we can simulate lunar
basaltic regolith with good accuracy and we do not need large
volumes compared to earth operations.  This could be a well-known
quantity long before the time a commitment has to be made.

>  This shows the absurdity of the claim that SPS technology is
>  available now, or could be had with an effort comparable to
>  the Apollo project.

Actually, it's easier.  Power transmission has been tested, at
Goldstone.  Rectennas are under development for powering high-flying
electric drone aircraft from the ground.  Propagation is fairly well
known.  The chemistry of lunar regolith is known.  Basic life support
in space is well-understood.  Etc, etc.  Most pieces of the puzzle
either exist already, or are under development.

>If SPS does get built, I predict: (1) it will be secondary to
>or in combination with other space activities that provide
>more immediate payoffs (like, cheaper launchers for comsats),

Combination sounds very likely.  The market for megawatt comsats
and continent-covering cellular phone services will not be small,
and all of those are natural combinations with, and possibly
precursors of, powersats.  These technologies feed on each other,
since powersats are large generators and stable platforms, which
MW broadcast sats and cellular-phone antennas require.  Any work
done on one makes the others immediately more feasible.

>and (2) the powersats will use lasers, not microwave beams.

I dispute this *very* strongly.  If the laser can operate through
the atmosphere and can put as little as 10 KW/m^2 on its target,
it is also a weapon.  Physically attractive, politically impossible.
Large spot size of SPS is an advantage, since it cannot select small
targets, and its low (230 W/m^2 max) power density is not acutely
harmful.  It cannot be used as a weapon.
--
  I am paid to write all of RSI's opinions.  Want me to write some for you?
[phone]        Forewarned is half an octopus.
Russ Cage, Robust Software Inc.            [e-mail]

------------------------------

Date: 2 Mar 90 18:37:54 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Astronomical telescopes for NASA spacecraft arrive at Goddard (Forwarded)

Paula Cleggett-Haleim
Headquarters, Washington, D.C.                     March 1, 1990

Randee Exler
Goddard Space Flight Center, Greenbelt, Md.

RELEASE:  90-34

ASTRONOMICAL TELESCOPES FOR NASA SPACECRAFT ARRIVE AT GODDARD

     The astronomical telescopes for NASA's Extreme Ultraviolet
Explorer spacecraft have been delivered to the Goddard Space
Flight Center (GSFC), Greenbelt, Md., for integration into the
Goddard-designed payload module and for subsequent environmental
testing.

     The scientific payload consists of four specially designed
telescopes that will make astronomical observations in the
previously unexplored portion of the electromagnetic spectrum
called the extreme ultraviolet, which is between the X-ray and
ultraviolet wavelengths.

     The integration and testing of the spacecraft at Goddard,
which includes mating the payload module to NASA's Explorer
platform spacecraft bus, is expected to take 18 months.  The
payload will be launched into low-Earth orbit aboard a Delta II
expendable launch vehicle from Cape Canaveral Air Force Station,
Fla., in August 1991.

     During its expected 2-year mission, the explorer spacecraft
will carry out an all-sky survey in the 100 to 1,000 angstrom
wavelength region and will subsequently include a program in
which guest investigators will be able to conduct spectroscoptic
observations of the brightest extreme ultraviolet celestial
sources.

     The spacecraft's science payload has been designed, built
and tested by the Space Astrophysics Group of the Space Sciences
Laboratory, University of California, Berkeley.  Professor Stuart
Bowyer is the principal investigator.  Dr. Roger F. Malina is the
principal investigator for the construction of the telescopes.
The project manager at Berkeley is Steven J. Battel.

     The science operations center for the telescopes will be
located at the University of California, Berkeley's Center for
Extreme Ultraviolet Astrophysics.  The payload operations control
center will be located at Goddard where Donald L. Margolies is
the spacecraft's mission manager.

------------------------------

Date:         Sat, 03 Mar 90 14:55:33 EST
From: Kenneth Ng <[e-mail]>
Subject:      Feynman (was fun space fact #1)


:Date: Mon, 26 Feb 90 10:20:09 PST
:From: [e-mail] (Peter Scott)
:Subject: Re: Fun Space Fact #1: Launcher Development Costs
:
:Well, Kutyna may have known as well, but in a talk which I attended at
:Caltech (which was later worked into an article, "Mr. Feynman Goes to
:Washington"), Feynman said that the day after he decided to join the
:commission, he went to JPL for an intensive meeting, and almost the first
:thing in the notes he took was the suggestion that the accident was due
:to O-ring failure in the SRB.  That page of his notes was reproduced in
:the article, wish I could remember where the darn thing was published.
:

From "What do YOU Care What Other People Think?", by Richard P.
Feynman, page 120:

   When I look at my notes now, I see how quickly they gave me hints
   about where to look for the shuttle's problems.  The first line of
   my notes says "Inhibit burning. Liner." (To inhibit propellent from
   burning through the metal wall of each booster rocket, there's a
   liner, which was not working right.)  The second line of my notes
   says, "O-rings show scorching in clevis check."  It was noticed
   that hot gas occassionally burned past the O-rings in booster-
   rocket field joints.

I'd recommend the book, as well as "Surely Your Joking Mr Feynman".
They both describe his various adventures/experiments/encounters
throughout his life.  And the luck that this guy has at times is
absolutely mind-boggling.

------------------------------

End of SPACE Digest V11 #109
*******************