Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V15_5/V15NO588.TXT

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Date: Wed, 23 Dec 92 05:17:12
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #588
To: Space Digest Readers
Precedence: bulk


Space Digest                Wed, 23 Dec 92       Volume 15 : Issue 588

Today's Topics:
                        Acceleration, cats...
                    Acceleration, Galileo, X-rays
      Air ops vs. space ops (was Re: DC vs Shuttle capabilities)
                 Aurora chase planes (was Re: Aurora)
                 cryptocraft photography, Re: Aurora
                          ground vs. flight
     I thinI see our problem. (Was Re: Terminal Velocity of DCX?
                            LEI financing
      MOL (was Re: Terminal Velocity of DCX? (was Re: Shuttle ..
MOL (was Re: Terminal Velocity of DCX? (was Re: Shuttle ...)) (2 msgs)
        Pilots must be stupid? (Re: DC vs Shuttle capabilities
    Stupid Shut Cost arguements (was Re: Terminal Velocity of DCX?
             The Real Justification for Space Exploration

    Welcome to the Space Digest!!  Please send your messages to
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----------------------------------------------------------------------

Date: Tue, 22 Dec 1992 23:04:43 -0600
From: [e-mail] (Phil G. Fraering)
Subject: Acceleration, cats...

My last post for a while... btw, thanks to whoever I'm stealing
the neat indenting from ;-)

In article <[e-mail]> [e-mail] (John Roberts) writes:
] That applies to things that are somewhat resiliant (like humans with their
] limbs not locked), because if deformation continues throughout the period
] of acceleration, then the entire body is not really subjected to the full
] acceleration. (For another example, putting rubber feet or a springy internal
] suspension in a piece of equipment can greatly reduce the maximum shock if
] you drop it.)

Anyone here seen that special they did on TV a while back, about
how some cats have fallen from ten or twenty stories and sometimes
survived (don't try this at home! don't try it with a cat! and especially,
it doesn't work well with humans!)?

What I want to know is, how the ability to fall from 100-150 feet
up was _selected for_ by evolution. It implies that they went through
a period of development where cats that could do that were outcompeting
cats that weren't, to the extent that a large number of cats today can
do it.

Especially since this isn't something that can be done gradually:
the adaptations don't help in falls of 30-60 feet, or much higher than
somewhere around 100 feet (I think)...


Phil

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

Date: Wed, 23 Dec 92 00:21:28 EST
From: John Roberts <[e-mail]>
Subject: Acceleration, Galileo, X-rays

-From: [e-mail] (_Floor_)
-Subject: Re: Acceleration
-Date: 22 Dec 92 22:04:05 GMT

-In article <[e-mail]> [e-mail] (John Roberts) writes:
-] That applies to things that are somewhat resiliant (like humans with their
-] limbs not locked), because if deformation continues throughout the period
-] of acceleration, then the entire body is not really subjected to the full
-] acceleration. (For another example, putting rubber feet or a springy internal
-] suspension in a piece of equipment can greatly reduce the maximum shock if
-] you drop it.)

-Hmmm...you think maybe rigidity has something to do with this?
-If something is rigid, it is much more likely to break than something
-flimsy, which will bend.

It's not that simple - you can also get reinforced oscillations, shock waves
that propagate through the structure (generating traveling wavefronts of
internal stress, which can perhaps reinforce, or be concentrated at certain
points), etc. Other things being equal, it's probably safe to say that you'd
prefer a structure that dissipates the energy of internal shock waves, and
an external structure that minimizes the transmission of such.

-Electronics certainly canot be built in
-a manner that will bend. Any flexing of the probe would have to
-be somehow accounted for in the design.

Electronic devices are not utterly inflexible - they do have some degree of
resiliance.

-] But other than that, and factors such as prolonged stress on human hydraulic
-] systems, the greater problem can be with rapid changes in acceleration, which
-] are of course associated with short bursts of acceleration. (I believe the
-] usual term for the time derivative of acceleration is "jerk".) These rapid
-] changes can cause very high internal stresses that are not found with slow,
-] steady increases in acceleration.
-]
-] Just as an example, compare your body lying in a bed with a downward
-] acceleration of one gravity, or being clamped in a device that repeatedly
-] shakes your body back and forth, with a maximum acceleration of half a gravity.
-] Which do you think would be likely to place more stress on your body, and
-] which would be quicker to cause discomfort? :-)
-]
-] John Roberts

-You're joking me if you think the Galileo probe will experience constant
-deceleration. There's going to be buffeting worse than we could imagine,
-I imagine (:-). Especially at speeds many times that of sound (which I'm
-sure will be different for the Jovian atmosphere)! So you're point is
-very applicable.

If you've ever seen video from inside the Shuttle during launch, you've
probably noticed that the astronauts are shaken pretty hard (at least
while the SRBs are thrusting). Payloads for launch are routinely tested
for resistance to vibration. I'd certainly *hope* that that's been factored
into the design of the Galileo atmospheric probe.

-Experiencing this jolting for milliseconds (as per
-a dropping watch) may not cause any damage. But if you dangled the watch
-from the ceiling and proceeded to place a jackhammer at its face,
-slamming into its face for a couple of minutes, liklihood is that
-the watch will no longer function! Ditto for an atmospheric probe.
-That thing is going to get one whale of a beating. You've helped me
-emphasize my point even more! Thanks :-)

- Gene Van Buren, Kzoo Crew(Floor), Washington U. in St. Lou - #1 in Volleyball

There are at least two mechanisms for damage from acceleration/vibration:
instantaneous peak load (which has nothing to do with continuation of
the forces much beyond the natural resonant period of the object), and
cumulative damage which gradually builds up. In either case, it's fun to
speculate on the stresses the probe will be subjected to, but idle to
attempt any authoritative claims unless accompanied by a large amount of
very nasty math, and detailed information on the structure of the probe.
I'm inclined to believe the Galileo people probably did their homework on it.

(I just read an article on testing portable personal computers for resistance
to damage. Among the tests were dropping them from desk height onto a
carpeted or uncarpeted concrete floor, putting them in a paint can shaker,
and running them through a (slightly padded) clothes dryer. Surprisingly,
most of the PCs survived at least some of the tests, and some of them survived
all of the tests! I also found a short article on portable PCs on the Shuttle -
I'll try to post some details next time I find the article. :-)

One factor I'm interested in - the generation of X-rays. Black body radiation
at 28000 degrees Fahrenheit ought to have a considerable amount of emission
at X-ray wavelengths. Unfortunately, the one book in the library that might
give the actual levels is checked out. Can anybody give an idea of the
magnitudes involved?

John Roberts
[e-mail]

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

Date: Wed, 23 Dec 1992 04:12:05 GMT
From: Greg Moore <[e-mail]>
Subject: Air ops vs. space ops (was Re: DC vs Shuttle capabilities)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Bill Higgins-- Beam Jockey) writes:
>In article <[e-mail]>, [e-mail] (Greg Moore) writes:
>
>See *2010*.  The first cosmonaut across uses an MMU.  She brings a
>rope with her.  Subsequent transfers are straightforward (if the
>engineers have done their jobs on handling of this tethered system!).
>
    Saw it. Also noticed several mistakes in it.  For example
at one point they had "gravity" in a non-rotating part of the ship. :-)
(Hmm, should have hired McClewin (sp?)

    Anyway, the key phrase is "... if the engineers...."  This will
take some practice and work.  The engineers thought they had modelled
Instelstat Vi rescue well.

    This by the way this one reason I support NASA's decision to
fly more EVA's.  I think the more experience in EVA the better.  Perhaps
it won't be an astronaut who doe sthe above, but an astronaut. :-)

> (deleted wing-walking/jerry can story.)  Very interesting though.

>Given proper equipment and training in both cases, an in-space
>transfer or refueling operation *is* less dangerous than the
>equivalent in mid-air.
>
>>     I'm not saying it can't be done, or that it won't be done.
>> Simply that some thought and PRACTICE will have to go into it.
>
>Right.
>
>Bill Higgins, Beam Jockey         | "I'm gonna keep on writing songs
>Fermilab                          | until I write the song
>Bitnet:      [e-mail]  | that makes the guys in Detroit
>Internet:  [e-mail]  | who draw the cars
>SPAN/Hepnet:      43011::HIGGINS  | put tailfins on 'em again."
>                                            --John Prine

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

Date: 23 Dec 1992 04:32:38 GMT
From: Pat <[e-mail]>
Subject: Aurora chase planes (was Re: Aurora)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (David Smith) writes:
>accompanying it?  (Mary's definition of "chase plane" is the standard
>one for testing aircraft but we're really talking about an "accompanying
>plane")  Unless there was some major manuevering going on you can't say
>that the F-15 was "chasing" or attempting to intercept with the intent
>of shooting it down or identifying an unknown plane rather than accompanying
>it as a "chase plane".


Mary, it didn't leap out at me from your post,  but I believe most chase planes
are loaded with a couple of cameras,  in the gun mounts and in the
cockpit, to try and record at or above  24 frames/second the behavior
of the experimental plane.  it is useful to know that a trim tab
tore off,  a minute before the test plane crashed.

I think fighters are preferred in this mode,  because with all the hard points
you have lots of places to stick cameras or sensors.

ALSO  IF, repeat IF  this is a real plane,  running Deep Black,  it may be
very worthwhile to try and conduct interception excercises  using
US front line fighters.  if it's made from stealth equipment  and has an
ECM suite capable of spoofing  the APS-6?  radar in the F-16,  then you
have an idea of wether you want to take the bird deep inside kazakhistan.

if on the other hand,  an F-15 or F-16 pilot is able to somehow get enough
of a skin paint during manuevers to get into visual  and then can jump
all voer the AURORA,  then maybe its not as good as one hoped.

One problem on most stealth aircraft is they still have bright angles.
even teh B-2  is visible at certain angles.

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

Date: Wed, 23 Dec 1992 06:45:34 GMT
From: [e-mail]
Subject: cryptocraft photography, Re: Aurora
Newsgroups: sci.space

My attempts to mail this reply directly to the poster kept failing 'unknown
host', so I ask the forbearance (so great it is) of the net for posting
this directly in the hopes Mr. McGwier will see it.  WHH

In article <[e-mail]>, [e-mail] (Bob McGwier) writes:
>>  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.
>
>
>
> From NE by N down to SW by S is <NOT> retrograde.  This is the descending
> half of a normal orbit with inclination less than ninety degrees.  Remember
> that in June, the north pole is in continuous sunlight.  We could figure out
> the EXACT height from your observations since we KNOW where the satellite
> will enter the `umbra' of its eclipse given by your observations.  If I have
> time, I will do this computation if not, given this someone else should be
> able to do the simple calculation.
>
> BMc



I thank you for your comment (this is the first chance I've had to log on
since I posted).  Several people have sent me comments directly with
several pieces of useful information and I am digesting those.

But I do not understand this comment (please don't take it that I am
disputing it - I want to understand, so I am asking for clarification).

The way I understand it, most satellites go around the earth from west to
east (direct or normal as described above).  A very few may have been
launched east to west, but it takes more energy and the advantages are
few.  Many are in near-polar orbits, (for survailance, etc.) with
inclinations near 90 degrees.  I've been told many of these are 98 degrees,
which would be 'retrograde'.  What I don't understand is this
"descending half of a normal orbit".   Suppose a direct (inclination less
than 90 degrees) satellite is ascending (has crossed the ascending node) and
heading north and east.  When it reaches the maximum north, it starts heading
south.  But it will still be drifting east as seen from an observer on
the ground under it (or above it for that matter).  Something that winds up
further west in the sky as it goes toward the equator must be 'retrograde',
with an inclination greater than 90 degrees.  (Ignoring the rotation of the
earth under it - but this was moving fast enough for that to be neglible.)
Now, maybe my visualization is wrong on this (I have no claim to
infallibility), but no one else I have discussed this with had the
interpretation you did, and I make my living in figuring where celestial
stuff goes, so it is important to me to get my own head right on this.

  I would appreciate further explanation of this statement - I do want
to know what it is I saw.

BTW, most calculations claim that for this to be illuminated by the
sun, it had to be 700 to 800 miles high.  Which makes its apparent size
even more difficult to explain.  And something that big, in full sunlight
should have been quite bright - which leads us to think it may have
been much lower - possibly in the atmosphere and illuminated by
ground lighting - which of course means it was not in a satellite
orbit at all....

Hoping for a clarification of your assertion,  Wm. Hathaway


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

Date: 23 Dec 92 05:10:56 GMT
From: Greg Moore <[e-mail]>
Subject: ground vs. flight
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Greg Moore) writes:
>>    I can recall only 1 (possibly 2) examples of astronauts
>>transferring between craft via EVA.  And in that case I believe
>>the craft were linked...
>>    I don't doubt that someday we'll see EVA between
>>non-docked craft...
>
>"Someday" was 1966, on Gemini 10.  And the target craft for the EVA wasn't
>even stabilized -- it was an old Agena, batteries long since dead.  Apart
>from the problems of EVA itself, which NASA was only just starting to
>discover, it wasn't a problem according to Michael Collins (who did it).
>
    I wasn't aware of this.  What did Michael Collins do while on
the Agena?
    BTW, it's partly the EVA itself I'm talking about.  We STILL
need more experience, lots.

>You might also want to look up the Solar Max retrieval (as originally
>planned), the Palapa/Westar retrieval, and the Leasat repair, all of
>which involved astronauts interacting with undocked craft.  The Leasat
>repair, in particular, was done by the Intelsat method:  slide the
>shuttle up close to the satellite and have an astronaut grab it (and
>Leasat was spinning, too).
>
    Good point.

>By the way, why do you assume the craft wouldn't be linked before crew
>or cargo transfer?  It would make sense to at least have an arm linking
>them first.
>
    You're right.

>On-orbit operations are a little bit harder than on-ground operations,
>for two reasons:  lack of friction, and the extra dimension of motion.
>On the ground, before you refuel (say) an aircraft, you make sure it's
>parked with its brakes locked.  The equivalent in orbit is to grab hold
>of it with an arm.  Still lots easier than for aircraft in flight.

    Agreed.  And the aircraft analogy was flawed.  BTW, what is
the maximum mass that the RMS can handle?
    BTW, what has the success rate been with the RMS on grabbing
stuff with a handle?  Anyone have any clue? 80% 90%?  Let's
not even consider the stuff it's had to attempt to grab that didn
have handles. I'd assume that DC-1 and any satellites it launches
has handles.  (They are cheap enough.)

>--
>"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
>       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: 23 Dec 92 04:43:01 GMT
From: Greg Moore <[e-mail]>
Subject: I thinI see our problem. (Was Re: Terminal Velocity of DCX?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Edward V. Wright) writes:
>In <[e-mail]> [e-mail] (Gary Coffman) writes:
>
>>I hope the DC program all works and we get cheap and frequent access
>>to LEO, but I don't think it'll operate at airliner costs or schedules,
>
>Gary, 50 years ago you would've been telling us that jet aircraft
>will never at what you now blithely dismiss as "airliner costs and
>schedules."  Hundreds of flights a day in and out of Dallas-Fort
>Worth?  Planes carrying hundreds of passengers each?  Ridiculous!
>Do you know how much it would cost to build just one runway for a
>plane like that?  A single airport would cost billions of dollars.
>There just isn't that much money in aviation -- not in the whole
>country.
>
    I think I see our problem here Edward.  What it sounds like to
me (I'm not saying this is what you said, but this is what I heard) is
that DC-1 will do this and that and this.
    In reality it sounds more like you are talking about DC-10,
DC-12, etc.
    Unless you are saying that a 747 is the same plane as a DC-3
was.
    If your claims are about 50 years from now, or even 20
eyars from now, I'll buy them.  If you claim they will all happen
within 5 years of DC-1 flight 1, I have my doubts.

>>It'll still be more cost effective to assemble and test
>>the bulk of space payloads on the ground and boost them to orbit
>>on larger capacity launchers, especially if some effort is put into
>>designing a heavy lifter for low labor costs.
>
>Just as it's more cost-effective to assemble and test
>office buildings at a central factory, then ship them
>to the worksite.  Especially if some effort is put into
>designing a heavy freighter for low costs. ;-)
>
    Just as it's more cost-effective to assemble and test
off-shore oil rigs ata  cnetral plant, then ship them to
the worksite.  Especially if some effort is put into designing
a heavy freighter for low costs. ;-)
    BTW, I believe Japan about 10 years ago DID build a manufacturing
plant and ship it to the Amazon via sea.  Why? because there
were no facilities in teh Amazon to do it.


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

Date: 22 Dec 92  23:33:22
From: [e-mail]
Subject: LEI financing
Newsgroups: sci.space

Henry, based on past performance, I would agree that the chances of passage of
the Lunar Resources Data Purchase Act were low. However, several things have
occurred this year that make it a better chance than in the past:

Daniel Goldin. Under his administration, NASA is saying and doing things that
would have been hard to imagine years ago. Their Procurement office is talking
about not only purchasing lunar, but also Martian, data as well. It is
possible that the LRDPA (what an acronym) may become obsolete next year, as
NASA may decide, through the President, to request funding for purchase of
lunar data.


Congress. This organization did pass the Launch Services Purchase Act, and did
extend it last year in certain areas. There is interest in the right places
for this type of legislative initiative.

I wouldn't say that passage of the Back to the Moon bill is a snap, but I will
say that the enemy of the Bill is not NASA, the Congress, or the lunar science
community - the enemy is apathy.

--- Maximus 2.01wb

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

Date: 22 Dec 92  23:32:02
From: [e-mail]
Subject: MOL (was Re: Terminal Velocity of DCX? (was Re: Shuttle ..
Newsgroups: sci.space

The Apollo Telescope Mount on Skylab was a recycled Lunar module. There was,
however, a Gemini hatch on the airlock....

--- Maximus 2.01wb

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

Date: 23 Dec 92 04:14:32 GMT
From: Pat <[e-mail]>
Subject: MOL (was Re: Terminal Velocity of DCX? (was Re: Shuttle ...))
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Pat) writes:
>>>>You heard wrong.  One MOL flew (unmanned).
>>>Could somebody provide data ?
>>
>>According to a friend of mine who was a MOL engineer.  One MOL flew
>>Manned.  only it was called ASTP.
>
>He's pulling your leg.  ASTP involved one Apollo, one Soyuz, and a docking
>module.  The docking module might perhaps have inherited a bit of technology
>from MOL, but no way was it a MOL.  For one thing, it was a fraction of the
>size.
>--



No,  this guy was quite serious.  he  said that something called "Apollo
Telescope Mount"  was the SOn of MOL.  It was my mistaken assumption that
that meant it had been recycled into the ASTP.  Dennis newkirk and i
have exchanged e-mail on this.  I am wondering if he was referring
to the astronomical section of SKYLAB?   he was dead serious about
this part,  i dont think he was having a go with me.

Henry,  do you think this was the case?  he implied that it had been
transmorged,  but that it still had a lot of MOL-like systems and fixtures.

pat

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

Date: Wed, 23 Dec 1992 04:02:29 GMT
From: Tom A Baker <[e-mail]>
Subject: MOL (was Re: Terminal Velocity of DCX? (was Re: Shuttle ...))
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Pat) writes:
>>>>You heard wrong.  One MOL flew (unmanned).
>>>Could somebody provide data ?
>>
>>According to a friend of mine who was a MOL engineer.  One MOL flew
>>Manned.  only it was called ASTP.
>
>He's pulling your leg.  ASTP involved one Apollo, one Soyuz, and a docking
>module.  The docking module might perhaps have inherited a bit of technology
>from MOL, but no way was it a MOL.  For one thing, it was a fraction of the
>size.

The very first MOL flight (and only one, if I recall correctly)
was basically a test of the Titan III, on its way to being man-rated.
(Does anyone remember if the strap-ons were solids?)  The MOL was a
mock-up, just a cylinder the right size and shape.  The Gemini capsule
was a donation to the Air Force from NASA, the former "Gemini 2"
capsule that had flown unmanned.

I think it all orbited for a few days before burning on reentry.  Yes,
it was certainly unmanned.

tombaker
#include <standard-disclaimer.h>

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

Date: 23 Dec 92 04:54:44 GMT
From: Greg Moore <[e-mail]>
Subject: Pilots must be stupid? (Re: DC vs Shuttle capabilities
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Edward V. Wright) writes:
>In <[e-mail]> [e-mail] (Greg Moore) writes:
>
>>The key words in your rebuttal are "...neither one is in contact
>>with the Earth."  Exactly.  I can't just "walk" from a DC-10 in
>>flight to a 747.  I can't just "walk" from a DC-1 to another
>>DC-1 in flight either.
>
>You can walk from one place to another carrying a four-ton
>cargo container?  On Earth?  I doubt it.
>
    Carry it while walking? no, but I can drive it.

>
>>Ever note how careful NASA is when it sends astronauts on EVA.
>
>About as careful as divers probably were when logging
>the first hundred man-hours on the first aqualungs.
>
    Again, I think I see were we are differing.  See my other
post on timeframes.  But to recap, I agree, after a couple thousand
more hours of EVA time, we'll have a lot more down.

>>They make sure they are somehow securred to the shuttle
>>or the RMS so that they don't accidently drift off.
>
>Divers can drift off, too.  And they have to worry
>a *lot* more about sharks. :-)
>
True... but astronauts have "Pigs in Space" to worry about.
A diver can swim back.  Or, with enough air (which they should
always have) resurface.  Astronauts are a bit more restricted.

BTW, as an aside, I seem to recall 1 mile or so as being a
useful limit for eyeball maneuvering in space. (i.e. you don't have
to worry about changing orbits trying to catch up to something,
you can jsut fly in a straight line.) Is this right?

>>And as for tranfering fuel while under way, my naval
>>knowledge is less, but I don't know too many groups of people
>>other than the military that do fuel transfers while in
>>motion.  It's generally a whole lot easier to come to a
>>dock, or at least anchor in calm water.
>
>So why do you assume that anyone who does inspace refueling
>will try to do it "under weigh" instead of docking first?
>
    Because I wasn't aware that DC-1 would have docking
capabilities.  If rather than insulting me, you had made this
clearer to begin with, I'd have shut up earlier.

>Oh, I forgot, we're assuming that the pilots are stupid. :-)
>
    No comment.

>
>>>We aren't talking air-to-air refueling either.  In-space refueling
>>>does not require split-second timing, only hooking up the hoses
>>>properly.
>
>>    Only.  Given the current understanding I have of DC-1,
>>(and please, correct me wrong if I am) there is no mechanism
>>for a drogue or probe.
>
>And the C-130's design didn't include cabbages.  That doesn't
>mean that if you needed cabbages someplace, you couldn't use
>the Herky bird to haul 'em there.
>
>Cargo planes are versatile.
>
>
>>    Now, one way I see around this is to redesign the DC-1
>>so that two can accomplish a hard-docking of some sort.
>
>What makes you think a DC-1 can't accomplish a hard docking.
>
    I wasn't aware that it could.  This I understand would
have to be an added capability?  HOw does it dock? through the
nose? or along the side?

>McDAC has artist's conceptions showing a DC-1 docked to
>space station Freedom.  That should tell you something.
>
    Thank you, it tells me a lot.

>
>
>
>No, we're being misquoted.  What we actually said was, "Lead,
>follow, or get the hell out of the way."
>
    Right, silly of me to object at all.

>
>
>
>
>
>
>

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

Date: 23 Dec 92 04:03:15 GMT
From: Greg Moore <[e-mail]>
Subject: Stupid Shut Cost arguements (was Re: Terminal Velocity of DCX?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>
>This number does not include NASA overhead, amortization of the orbiter,
>amortization of Shuttle development costs, and a host of other costs. Adding
>those in puts the cost at well over a billion per flight. Hell, interest
>costs on development alone adds over a quarter billion per flight (BTW,
>this interest is not a sunk cost since it is part of the national debt and
>we are paying for it even now).
>
    I thought you said that McDac or SDIO was going to treat
development costs of DC-1 as sunk costs.  Or is that just DC-X (in
which case, what exactly does that mean?).  If this is teh case, than
you have to treat the shuttle development costs as sunk costs.
As for amortization of the orbiter, the same rule applies to that
as any aircraft or spacecraft, including, DC-1.  The more you
fly it, the less this matter.  Right now, if you stopped all flights,
you could argue this cost (excluding interest) is about $150 million
a flight. (10 flights/orbiter, $1.5 Billion per orbiter).  This
number will shrink.
    As for interest based on the national debt, that's a slippery
one what I won't touch.  One question I have though, will you treat
any government financing for DC-X,Y the same way, i.e. consider
interested on national debt?)

>  Allen
>--
>+---------------------------------------------------------------------------+
>| Allen W. Sherzer | "A great man is one who does nothing but leaves        |
>|  [e-mail]     |  nothing undone"                                       |
>+----------------------123 DAYS TO FIRST FLIGHT OF DCX----------------------+

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

Date: 23 Dec 92 00:43:24
From: Brian Yamauchi <[e-mail]>
Subject: The Real Justification for Space Exploration
Newsgroups: sci.space,talk.politics.space

It seems to me that all of these spinoff arguments, Malthusian
arguments, and "dinosaur killer" arguments miss the point.

Asking "why explore space?" is like asking "why feed the starving?",
"why create art?", or "why do basic science?"  It all comes down to
basic human drives, and I would argue that the drive to explore is
just as basic as the drive to help, to create, or to learn.

The major achievement of Apollo was not Teflon.  The major achievement
of Apollo was putting a man on the moon.

When Sir Edmund Hillary was asked why he climbed Everest, he answered,
"Because it's there."  The same answer is just as appropriate for why
we explore space -- because the entire universe is out there...

Yes, there are pragmatic near-term benefits of space commerce, but
most of those don't extend far beyond geosynchronous orbit.  And there
are many long-term benefits likely to accrue from interplanetary space
development, but most of those will be _very_ long-term.

At some level, perhaps the most honest answer to the "why explore
space?" question is the simplest -- "If you have to ask, you'll never
understand."
--
_______________________________________________________________________________

Brian Yamauchi            Case Western Reserve University
[e-mail]    Department of Computer Engineering and Science
_______________________________________________________________________________

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Again, the Lunar Resources Data Purchase Act will provide a solid funding base
for a resumption of lunar science flights. Congress didn't fund NASA's lunar
orbiters, because of the fear that a new start for SEI hardware would be an
implicit new start for a manned return to the Moon (remember, that was George
Bush's proposal). This new approach alleviates that concern, but does get us
lunar science data soon.

--- Maximus 2.01wb

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End of Space Digest Volume 15 : Issue 588
------------------------------