Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V15_5/V15NO573.TXT

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Date: Sun, 20 Dec 92 05:01:24
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #573
To: Space Digest Readers
Precedence: bulk


Space Digest                Sun, 20 Dec 92       Volume 15 : Issue 573

Today's Topics:
                            Apollo 13 book
Breeder reactors (was Re: Justification for the Space Program (2 msgs)
                             Chicken guns
                 cryptocraft photography, Re: Aurora
                           DoD launcher use
             Justification for the Space Program (3 msgs)
   People who can't count costs (Was Re: Terminal Velocity of DCX?)
                        Shuttle thermal tiles
                         Space power systems
       Terminal Velocity of DCX? (was Re: Shuttle ...) (3 msgs)
                         {pace power systems

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Date: Sun, 20 Dec 1992 00:22:04 GMT
From: Henry Spencer <[e-mail]>
Subject: Apollo 13 book
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Brian Stuart Thorn) writes:
> "Houston, We've Had a Problem" is a NASA/Government Printing Office
> non-technical account of the Apollo 13 accident. It is about a ten
> page magazine-sized booklet.
>
> I only know of one other "book" about the accident, that being
> "13: The Flight That Failed". I think the author was Henry S.F. Cooper...

Correct.  H,WHaP is pretty lightweight.  Cooper's book is the most detailed
treatment I've seen.  I'm not aware of any other books entirely on the
accident.

Murray&Cox's "Apollo" does a good job on Apollo 13.
--
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: 19 Dec 92 20:36:26 GMT
From: "Brendan B. Boerner" <[e-mail]>
Subject: Breeder reactors (was Re: Justification for the Space Program
Newsgroups: alt.rush-limbaugh,talk.politics.space,sci.space

In article <[e-mail]> [e-mail] (Paul Dietz) writes:
>Breeder reactors exist today.  The technology for reprocessing
>nuclear fuel exists.  Better, cheaper technologies for this are
>in the works (the pyroprocess being developed at ANL, for example).
>They are not moving faster because we have such an embarrassing
>glut of energy.

Speaking of breeder reactors, why doesn't the U.S. have more of
them?

Brendan
--
Brendan B. Boerner        Phone: [phone]
Internet: [e-mail]    MHS: bboerner@novell
Please use ^^^^^^^^^^^^^^^^^ if replying by mail exterior to Novell.

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

Date: Sun, 20 Dec 1992 00:28:16 GMT
From: Henry Spencer <[e-mail]>
Subject: Breeder reactors (was Re: Justification for the Space Program
Newsgroups: talk.politics.space,sci.space,alt.rush-limbaugh

In article <[e-mail]> [e-mail] (Brendan B. Boerner) writes:
>>Breeder reactors exist today.  The technology for reprocessing
>>nuclear fuel exists.  Better, cheaper technologies for this are
>>in the works (the pyroprocess being developed at ANL, for example).
>>They are not moving faster because we have such an embarrassing
>>glut of energy.
>
>Speaking of breeder reactors, why doesn't the U.S. have more of
>them?

Limited demand (as Paul said) and massive political problems.  The choice
of the fast breeder may also have been a poor one; there are alternatives.
(The whole US nuclear-power enterprise has suffered from early decisions,
arguably premature, to concentrate on one or two reactor types and give
little or no attention to others.)
--
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: Sat, 19 Dec 92 18:22:56 EST
From: John Roberts <[e-mail]>
Subject: Chicken guns

-From: [e-mail] (Pat)
-Subject: Re: Chicken Guns (was Re: "trivial engineering")
-Date: 18 Dec 92 18:15:34 GMT
-Organization: UDSI

-The F-16 in the early 80's was having a real problem with bird strikes
-fracturing the canopies, so i heard for a while the air force
-was launching Frozen turkeys and chickens at the aircraft
-to test canopies.  i guess the frozen bit was to make the birds
-harder.

I've heard that birds sometimes get caught in an updraft and frozen.

Fortunately, it doesn't seem to happen very often, and aircraft can
presumably avoid such updrafts.

John Roberts
[e-mail]

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

Date: 19 Dec 92 06:38:45 GMT
From: I Forgot <[e-mail]>
Subject: cryptocraft photography, Re: Aurora
Newsgroups: sci.space

In <[e-mail]> [e-mail] writes:

>In article <[e-mail]>, [e-mail] (Dean Adams) writes:

>>
>> [e-mail] (Anthony J Stieber) writes:
>>>[e-mail] (Dean Adams) writes:
>>  >>Were there any photos of the F-117A prior to the official release?
>>  >>I don't beleive so, even though it flew for almost a decade.
>>  >Yes, at least one in AW&ST, July 10, 1989, p22.
>>
>> Yes... but the "official release" that I was speaking of took place on
>> November 10, 1988.  That is when the AF first acknowledged the F-117As
>> existence and released a single photo (which AW&ST of course printed :).
>>
>>  >This is sometime after the first flights of the craft in 1981, but of
>>  >course all the early flights were done exclusivly at night.
>>
>> The Have Blues flew in 1977, and the first F-117A flew on June 18, 1981.
>> In all that time it seems nobody really managed to catch a good view of
>> them on film (at least nobody without a Senior Trend clearance :)
>>
>>  >I'm sure there will be pictures of whatever this/these craft are.
>> I'll certainly be waiting...  It may be a while though.
>>
>>  >Someone with camera and a telescope lens will catch it.
>> The sky is awfully BIG...
>>

>Yes, indeed, it includes everything up there...

>However, there are a lot of people observing.  I wish the following
>observation could have been recorded on film or tape, but it was a
>visual observation by two people of something we have not yet nailed
>down.  If the following were a satellite, it either had to have been
>high up (notice it was seen after midnight EDT) or been low enough
>to pick up and reflect sufficient ground illumination.  All attempts
>to match it with known satellites have found nothing. Perhaps it
>was a sighting of this whatever???  I'd sure like to ID it.
>Serious comments most welcome.

>  description of observation:

>    Observation:  Unknown
>    Observers:    I. Cooper, W. H. Hathaway
>    Date:         night of 8-9 JUN 1991
>    Time:         ~3-5 minutes both before and after 12:40:30 am EDT
>                  - this time checked via phone while object was
>                  being followed
>    Site:         Severn MD,  Long: 76 Dg 38 Mn W, Lat: +39 Dg 11 Mn
>    With:         10" f/6 Cave Astrola
>    Eyepiece:     28mm Meade Orthoscopic
>    R.A./Dec:     picked up while sweeping for NGC6829 in Cygnus,
>                  roughly 19-20 Hr, + 50 Degrees,
>                  followed continuously to vicinity of northern Ophiuchus
>                  roughly 16-17 Hr, + 10 Degrees,
>                  until obscured by leaves of large maple tree
>    Magnitude:    roughly 8th magnitude
>    Appearance:   ! extended object !, shaped somewhat like a horseshoe, but
>                  sides squeezed together, or like a sharply closed
>                  boomerang.  Overall size, roughly 1 arcminute.
>                  (eye-ball comparison with disk of Jupiter)
>                  Each 'arm' maybe 20 arcsec in width, 40 arcsec in length,
>                  and the black space between the arms about 10 arcsec in width.
>                  It looked much like the picture of HST on page 32 in the
>                  July 1991 Sky and Telescope, but more "U" or "V" shaped
>                  rather than the skewed "H" shape.  Note that was 1 1/4
>                  arcSECONDS across from a distance of 1000 kilometers.
>                  The surface texture was reminescent of a planetary nebula,
>                  though with less surface brightness than the Ring Nebula.
>                  Slight color - creamy, light brown to tannish - not
>                  distinguishable from solar reflection.
>                  Starlight clearly seen in the 'notch' between the arms.
>                  Starlight possibly visible when passing behind each arm.
>                  The direction of motion was _not_ along the axis of the
>                  arms, more like 45 degrees from their intersection.
>                  No point or point-like lights, no navigation lights,
>                  colored nor white.  Sketch made immediately afterward.
>
>  Identification: It had all the familiar steady motion of an
>                  Earth satellite, but _not_ in a common Direct orbit from
>                  West to East.  Motion actually more like from NE by N to
>                  SW by S.  If a satellite, it was in a near-polar orbit, but
>                  Retrograde.

>Wm. Hathaway



Just a couple observations.  Having done some studies of the Soviet space
programs, I found that most of their lower orbit satellites that need polar
type orbits, are in retrograde orbits.  This is due to problems with launch
sites being located inland and having populated areas downrange.  I heard
a couple stories of lower stages dropping into populated areas during the
early 70's.  Along with these polar retrograde orbits, their early warning
satellites use highly eliptic (sp??) orbits to maximize there time over
targets.  These orbits result in, well, sort of 'wave type' looking ground
tracks with segments that do go ne to sw.  The polar orbits sats I'm looked
at most were the weather sats and I didn't find much on there intelligence
gathering sats.  I would guess, from looking at other systems, these would
also have retrograde, very low polar orbits. (weather sats are up at 950 to
1200km were as 'spy sats' are probally down around 200-250km.)

Well, who knows, maybe it was that UFO they showed on "Sightings" tonight
that was filmed by the shuttle.

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

Date: 19 Dec 92 17:21:27 GMT
From: Pat <[e-mail]>
Subject: DoD launcher use
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>In article <[e-mail]>, [e-mail] (Gary Coffman) writes:
>
>Furthermore, you assumed that the KH-11 is the benchmark (also known as
>the Szabo yardstick) without the resultant drop in costs which would occur if
>you could rapidly deliver sats to orbit.
>
>You don't have to add lots of fuel, thrusters, and other sensors, treat the
>camera and sat as a throw-away item.
>



Doug,  actually the problem with both the KH-11 and 12 is that they were
done as totally black world projects.  costs over-run like crazy
because there are no competitors,  little oversight and security
over head costs galore.

I think if you built light recon sats as just ordinary classified
projects, you could do it for a heck of a lot less.  part of the problem
with these birds is that they are built with multi-year lifetime and
super rad hardening.  you are right on when you say they should
be throwaways.

look at the russians.  they launch one-two a week and used to
burn them up manuevering them because they had plenty to go.

we should look to develope cheap sats to go with DC-1.

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

Date: 18 Dec 1992 21:56 CST
From: [e-mail]
Subject: Justification for the Space Program
Newsgroups: alt.rush-limbaugh,talk.politics.space,sci.space

In article <[e-mail]>, [e-mail] (Paul Dietz) writes...
>In article <[e-mail]> [e-mail] (Michael Robert Williams) writes:
>
>>I read an article in the British Interplanetary Society Journal about
>>a guy named Forrester (or was it Fisher?) at MIT who had done some
>>predictive world modelli, tracking several variables like population,
>>pollution, natural resource usage, standard of living, etc. Some of
>>his assumptions may have been...incorrect, buI didn't see anything
>>that looked grossly unreasonable. He projected the world 500 years
>>into the future toee what trends we could expect (yeah yeah, I know
>>don't trust computer numbers at first glance, especially extrapolations
>>that far in the future, but even with that caveat, the numbers are
>>scary).

[stuff deleted]

>
>
>This is all *so* ludicrous.  You are refering to results from the
>infamous "Limits To Growth" study.  It's been widely disparaged as so
>simplified as to be useless (for example, aggregating all "pollution"
>into a single variable.)  It's propaganda masquerading behind computer
>models.
>
You are half right. The limits to growth study did not consider space
resources at all, thinking that they would have zero impact.  The models
that are usually grouped into the "Malthusian" box to derive their genesis
from the Club of Rome studies.

By the way, our new Vice president is an adherent to these models so don't
blithly discount their impact on public policy.  Also there are many other
very powerful people in the U.S that have bought the Doomsayers predictions
hook line and sinker, such as Ted Turner of CNN fame. (Oh and his wife Jane)

>Much more believable results have been obtained by actually studying
>specific resources here on earth.  When you do that, and when you take
>into account technological improvements, the idea that things are
>going to necessarily go to hell just evaporates.

Believable by whom? You? Well all of these extrapolations and any belief in
them are acts of faith. You believe what you choose. Sophmore calculus teaches
the fallacy of extrapolating a value beyond the known data point.

>
>The 1500 year figure you present is a figment of your imagination.
>Come on -- technology is going to be rather different by the time the
>year 3500 rolls around, space exploration or not.  You can't possibly
>have any idea what technology will be like even 100 years down the
>road, let alone 1500.

Yes technology will be a lot lower, if we let those who are vigorously
promoting a turn from technology development to get the upper hand. Doubt this
you do? Look then at the trends in funding for technology development worldwide.
It was a great surprise when I read in Pliny's (Roman naturalist) how he
decried the loss of the impetus to develop new technology and how this lack
was coming back to drain the Empire of its very life and vigor. (Pliny 214-xx)

>
>The fundamental limit to resource exploitation is imposed by
>availability of energy, and space exploitation is *not* needed to get
>essentially inexhaustible supplies of that.

Oh really? Tell us how you intend to accomplish that? No one else has. True,
if we get cheap fusion we can drive the cost of energy way down. Too bad we
are a long way from that. The demand for energy to support a world population
at a standard of living comparable to the industrialize nations would mean
a two order of magnitude production increase in the supply of energy, and
material resources, with it's attendant pollution, both chemical and thermal.
To blithly deride the space option by pointing to technology tha does not
exist or is even on the horizon is irresponsible.

>
>The argument *against* spending money on unprofitable space activities
>is that our descendants would be better off if we spent the money on
>capital formation here on earth, so that they will be more prosperous
>(and, if they like, go into space).  We are able to launch rockets now
>not because the Victorians wanted to go the moon, or because they sent
>explorers to Antarctica, but because they had the industrial revolution.
>
>    Paul F. Dietz
>    [e-mail]

Captial formation means wealth. This has been the driver of civilization for
at least four thousand years. Where there is wealth there is plenty. In the
past, wealth generation has come in Three ways:

Natural resource explotiation
Economic activity redistributing the wealth to the more productive
War and conquest

The only truly platible, long term solution to the problem of not enough wealth
is clearly option one. Option two breeds option three by the jealousy endengered
by the winner of the economic war. (Remember Japan went to war with the US
because we were denying them natural resources, "economic sanctions")

Sorry Paul but go to any freshman chemistry class in college today and listen
to the litany of scarce resources. We are still going forward because we are
taking resources from the third world. What happens when those are gone?
What happens when the third world wakes up and says that they are gonna keep
their resources to fuel their own climb to prosperity?

Without the temporary diversion of resources to build a solar system wide
transportation structure that will allow the exploitation of the nearly
limitless resources of the solar system, we will eventually hear the
beating of the hooves of the four horseman of the Apocalypse. The gulf
war and Somalia are only the first shots in a new an dangerous era. How much
more expensive will it be in lives and dollars spent, to continue as we
are today?

Dennis, University of Alabama in Huntsville.

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

Date: Sat, 19 Dec 1992 14:35:17 GMT
From: Paul Dietz <[e-mail]>
Subject: Justification for the Space Program
Newsgroups: alt.rush-limbaugh,talk.politics.space,sci.space

In article <[e-mail]> [e-mail] writes:

 >>Much more believable results have been obtained by actually studying
 >>specific resources here on earth.  When you do that, and when you take
 >>into account technological improvements, the idea that things are
 >>going to necessarily go to hell just evaporates.

 >Believable by whom? You? Well all of these extrapolations and any belief in
 >them are acts of faith. You believe what you choose. Sophmore calculus teaches
 >the fallacy of extrapolating a value beyond the known data point.

Believable in the sense that they are grounded in actual study
of physical reality, not airy untestable abstractions.  For example,
going out and actually studiny geological abundance, and demand
for, various elements.

 >>The 1500 year figure you present is a figment of your imagination.
 >>Come on -- technology is going to be rather different by the time the
 >>year 3500 rolls around, space exploration or not.  You can't possibly
 >>have any idea what technology will be like even 100 years down the
 >>road, let alone 1500.

 > Yes technology will be a lot lower, if we let those who are vigorously
 > promoting a turn from technology development to get the upper hand.
 > Doubt this you do?

Yes, I doubt it.  The idea that we're going to get locked
in some sort of technological stasis is a bizarre fantasy.  Technology
is continuin to advance smartly.

Of course, if you've made the bad decision to go into an area with a
doubtful future -- like defense, or space, or fusion -- you might see
things differently.


 >>The fundamental limit to resource exploitation is imposed by
 >>availability of energy, and space exploitation is *not* needed to get
 >>essentially inexhaustible supplies of that.
 >
 >Oh really? Tell us how you intend to accomplish that? No one else has.

Endless people have, wingnut!  It's called fission.  There is sufficient
uranium and thorium in the earth's crust to supply current levels
of primary energy consumption for billions of years, if used with one
of the several breeding cycles.  Moreover, there is enough fossil
fuel around that we needn't go to fission right away.

The idea that we are near some sort of irretrievable collapse due to
exhaustion of energy sources just doesn't have any basis in fact.


 >if we get cheap fusion we can drive the cost of energy way down. Too bad we
 >are a long way from that. The demand for energy to support a world population
 >at a standard of living comparable to the industrialize nations would mean
 >a two order of magnitude production increase in the supply of energy, and
 >material resources, with it's attendant pollution, both chemical and thermal.

Get your arithmetic straight.  Current world energy consumption is
about 350 exajoules per year.  In the US, we consume about 3x10^11
J/year/capita.  A population of 10^10 consuming energy at our level
would increase demand about 1 order of magnitude.  If they consume
energy at the level of, say, current europeans, the demand would be
lower.

Direct thermal pollution at this level would not be of global importance.
Chemical pollution?  There's no law of nature that says chemical
pollution cannot be reduced as far as we like.  Certainly replacing
fossil fuels with nuclear-derived energy sources would reduce
this pollution greatly.

 >To blithly deride the space option by pointing to technology tha does not
 >exist or is even on the horizon is irresponsible.

Breeder reactors exist today.  The technology for reprocessing
nuclear fuel exists.  Better, cheaper technologies for this are
in the works (the pyroprocess being developed at ANL, for example).
They are not moving faster because we have such an embarrassing
glut of energy.

So-called "renewable" resources are less well developed, but
are on a steeper learning curve.  We can expect them to get cheaper
as well,

To baldly proclaim that space is essential, when it's orders of
magnitude away from being competitive, and when multiple alternatives
exist, is irresponsible at best, and (if coming from one feeding
at this particular trough) banal at worst.

 >Captial formation means wealth. This has been the driver of civilization for
 >at least four thousand years. Where there is wealth there is plenty. In the
 >past, wealth generation has come in Three ways:
 >
 >Natural resource explotiation
 >Economic activity redistributing the wealth to the more productive
 >War and conquest
 >
 >The only truly platible, long term solution to the problem of not
 >enough wealth is clearly option one. Option two breeds option three by
 >the jealousy endengered by the winner of the economic war. (Remember
 >Japan went to war with the US because we were denying them natural
 >resources, "economic sanctions")

Complete and utter crap!

The most important driver of wealth creation is accumulation
of *knowledge*.  Economies can and do grow, and people get
wealthier, in the absence of increases in resource exploitation.


 >Sorry Paul but go to any freshman chemistry class in college today and listen
 >to the litany of scarce resources. We are still going forward because we are
 >taking resources from the third world. What happens when those are gone?
 >What happens when the third world wakes up and says that they are gonna keep
 >their resources to fuel their own climb to prosperity?

Then we go to lower grade deposits, or use substitutes.  You are
repeating the Malthusian nonsense here (along with a line of
politically silly gibberish about exploiting the 3rd world.)

The third world "waking up": just why do you think they're selling
their resources?  Because you can't eat copper or cobalt, and, absent
the real drivers of wealth -- a knowledgable population backed
up by accumulated capital -- these resources are just useless lumps.

To get specific, just which resource are you talking about?  I tell
you what: you mention one, and I'll demonstrate that we can either
tolerate price increases (because so little is used), can find other
sources, or can substitute.

    Paul F. Dietz
    [e-mail]

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

Date: Sun, 20 Dec 1992 01:11:41 +0000
From: Chris Marriott <[e-mail]>
Subject: Justification for the Space Program
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:

>In article <[e-mail]> [e-mail]
> (Paul Dietz) writes:
>>Breeder reactors exist today.  The technology for reprocessing
>>nuclear fuel exists.  Better, cheaper technologies for this are
>>in the works (the pyroprocess being developed at ANL, for example).
>>They are not moving faster because we have such an embarrassing
>>glut of energy.
>
>Speaking of breeder reactors, why doesn't the U.S. have more of
>them?
>
>Brendan
>--
>Brendan B. Boerner              Phone: [phone]
>Internet: [e-mail]   MHS: bboerner@novell
>Please use ^^^^^^^^^^^^^^^^^ if replying by mail exterior to Novell.
>
>

As a matter of interest, the British government recently announced the
cancellation of the experimental fast breeder reactor programme at
Dounraey, Scotland.  This reactor has been in operation for many years,
producing electricity and selling it to the National Grid.  The cancellation
of this programme will result in the loss of 350 jobs at the UK Atomic
Energy Authority (for whom I work).  Tragic to effectively throw away
decades of work in this manner.

Chris
--
--------------------------------------------------------------------------
| Chris Marriott                           | [e-mail]    |
| Warrington, UK                           | BIX: cmarriott              |
| (Still awaiting inspiration              | CIX: cmarriott              |
|  for a witty .sig .... )                 | CompuServe: 100113,1140     |
--------------------------------------------------------------------------


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

Date: 18 Dec 1992 21:28 CST
From: [e-mail]
Subject: People who can't count costs (Was Re: Terminal Velocity of DCX?)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Edward V. Wright) writes...
>In <[e-mail]> [e-mail] (Josh 'K' Hopkins) writes:
>
>>HE indulged in creative accounting?  I think the contract for DC-X was $58
>>million, not a "couple hundred million."
>
>That sounds right.  McDAC has also spent some of its own money in
>addition to what it got from the Air Force.  I believe the contract
>required McDAC to spend at least an equal amount, so that puts it
>into the hundred-million-dollar range.  *Not* the billion-dollar
>range.
>
>
>>The average total cost of a shuttle mission is a little over $500 million
>>not a billion+.
>
>Only if you learned math from the "Hitchhiker's Guide."
>
>Divide the amount of money NASA spends on the Space Shuttle program
>every year by six flights per year.
>
>$500 million ain't even close.
>

FLAMETHROWER ON

Hey stupid don't you read this group? The marginal cost for a Space Shuttle
mission is $37 million dollars maximum. This is the cost of fuel, ET and
operations directly chargeable to the mission.

For those who are further mentally deranged and who love to count more of
the costs to the Shuttle program, the figure is $368 million dollars. This
includes the cost of the standing army at KSC and ranges around the world
and almost all charges to the program.  This rises to $405 million dollars
if you include the cost of the TDRSS program, the ASRM program, all shuttle
upgrades and modifications over the life of the program.

The flight rate by the way oh thou ignorant of basic math is 8 this year
with four flights scheduled in the first four months of next year. It is
beginning to be obvious that the flight rate of 8 per year is more of a
political than technical nature. If you were to account in this manner
the costs are even lower.

ONLY if you take every single budget item in the entire NASA budget that has
any relationship to manned space activities and then divide by the number
of flights per year, then you will get a >$500 million per flight costs.

These numbers come from the Space News article of Nov 29 December 8. Where
the heck do your numbers come from?

By the way, it is too bad Allen did not have the guts to respond to my
previous message relating these figures. I am flat sick and tired of people
simply ignoring any information that is detrimental to their little pet
project, no matter how valuable that project is in and of itself.

Dennis, University of Alabama in Huntsville

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

Date: Sat, 19 Dec 92 18:11:15 EST
From: John Roberts <[e-mail]>
Subject: Shuttle thermal tiles

-From: [e-mail] (Henry Spencer)
-Subject: Re: Shuttle thermal tiles
-Date: 19 Dec 92 00:54:41 GMT

-Anybody know if anything's been released on Buran's tile technology?
-Allegedly the Buran tiles are not as long-lasting, but they're tougher.

They're also much shinier than Shuttle thermal tiles.

John Roberts
[e-mail]

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

Date: Sat, 19 Dec 92 17:25:54 EST
From: John Roberts <[e-mail]>
Subject: Space power systems

-From: [e-mail] (Paul Schuytema)
-Subject: {pace power systems
-Date: 19 Dec 92 17:50:38 GMT

-Call for help:
-I am a freelance writer and I am currently working
-on an article for Omni on space power systems.
-I am interested in solar, nuclear, and other power
-systems which will be used for basic power
-(life support, computers, etc.) for manned missions,
-especially such things as space stations, Mars runs,
-and deep space xplorations.  I am interested not only in what
-is currently being developed, but also "far flung" ideas.
-I would like to correspond with interested researchers and
-elp.

Just to mention a few of the less obvious systems:

Solar Power: photovoltaic systems are fairly well known, but solar thermal
systems less so. They typically would use huge lightweight mirror systems
to concentrate sunlight, and use the concentrated energy (plus a heat sink)
to drive a heat engine, usually a mechanical closed-cycle device (Stirling
cycle).

Nuclear power: RTGs (radioisotope thermal generators) are fairly common,
and nuclear fission is sometimes used. In both cases, I believe the mechanism
is heat used to operate a thermocouple (inefficient, but there's plenty of
power available). The Atomic Energy Commission used to study a system I haven't
heard about in years - a nuclear battery that uses beta decay (I think) to
generate thousands of volts at perhaps a few microamperes.

Magnetic effects: for spacecraft in non-polar orbit around the Earth, it's
possible to interact with the Earth's magnetic field, to convert orbital
energy to electric power, or vice versa. (The latter is probably more useful -
a satellite can use solar power to boost its orbit.) The Tethered Satellite
System (TSS) recently flown aboard the Shuttle is such a device.

And of course the "futuristic" possibilities include fusion, matter-antimatter
reactions, interactions with the sun's magnetic field or the solar wind,
and power beamed from the Earth or some other site via laser or microwaves.

If you get your article published, please post the date of the issue it's
in - I'd like to see that.

John Roberts
[e-mail]

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

Date: 19 Dec 1992 16:51:58 GMT
From: Pat <[e-mail]>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Josh 'K' Hopkins) writes:
>
>HE indulged in creative accounting?  I think the contract for DC-X was $58
>million, not a "couple hundred million."  The average total cost of a shuttle
>mission is a little over $500 million not a billion+.
>



I believe this is called "szaboing " it:-)

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

Date: 19 Dec 92 17:02:45 GMT
From: Pat <[e-mail]>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Greg Moore) writes:
>
>    Given a figure of $500 Million a flight, useful work can be:
>10 hours/day * 6 astronauts * 5 days = 300 hours.  Divide this into the
>above number nd you get $1.6 Million.  If this is a EDO flight of 10
>days, your on-orbit costs drop in half.  So, I'd assume that
>


I think your number is a tad optimistic.  I think the shuttle suits
are only good for 4-5 Hours, before a recharge is done.
Also While you have a crew of 7,  at least two would stay in board.
The pilot and the Arm operator (He may need an assistant).
Henry is the roving expert on this.  so I get.
(oops,  also i guy stays suited up in the airlock  as an emergency helper.
8 hours/day (2 suit sorties) * 4 astronauts * 5 days = 152 hrs.
Less if you need another guy on the flight or middeck.
so i ball park it in at 3.5 million/hour.  not counting additional
depreciation on the suits.

I would imagine the CIS is still making a killing at 5 million/hour.

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

Date: 19 Dec 1992 17:10:11 GMT
From: Pat <[e-mail]>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Greg Moore) writes:
>In article <[e-mail]> [e-mail] (Brian Stuart Thorn) writes:
>> has the RMS. No RMS scheduled? Add it to a mission and then add SVS.
>    This would work except for one major requirement of the SVS, a
>clear payload so that visibility and movement wasn't hindered.


Here seems a stupid one?

SVS needed a clear payload bay in order to test full arm extension.???

Now when a satellitte is carried up, it is inside some shrouds and often
a turntable spinner.  Also bigger payloads are on racks.

Why not towards the last day of flight,  EVA two astronauts and jettision
the miscellaneous hardware.?  sure it's sapce junk,  but they could
wrap it all together on some cables and deploy a large mylar drdrogue
shield so it's radar visible and has high atmospheric drag.  it should come
down in a few years, if the drag is sufficient.

any guesses?

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

Date: 19 Dec 92 12:33:16 EST (Sat)
From: [e-mail] (Paul Schuytema)
Subject: {pace power systems

Call for help:
I am a freelance writer and I am currently working
on an article for Omni on space power systems.
I am interested in solar, nuclear, and other power
systems which will be used for basic power
(life support, computers, etc.) for manned missions,
especially such things as space stations, Mars runs,
and deep space xplorations.  I am interested not only in what
is currently being developed, but also "far flung" ideas.
I would like to correspond with interested researchers and
elp.
-Paul C. Schuytema

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

End of Space Digest Volume 15 : Issue 573
------------------------------