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Date: Tue, 2 Mar 93 05:00:13
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V16 #246
To: Space Digest Readers
Precedence: bulk
Space Digest Tue, 2 Mar 93 Volume 16 : Issue 246
Today's Topics:
Aurora (rumors) (4 msgs)
Cheap Mars Rocks (was Re: Moon Dust For Sale)
Hopkins Leaks (was Re: Blimps)
Human Distance Record:Apollo 13
Instead of Fred.. ETCo?
Reliable Source says Freedom Dead, Freedom II to be developed
Request for info about Ecuations and constants
SOLAR gravity assist? Yup.
Space Calendar - 02/27/93
Spy Sats
SSF Resupply (Was Re: Nobody cares about Fred?) (2 msgs)
SSTO Estimates (was Re: Refueling in orbit)
Welcome to the Space Digest!! Please send your messages to
"space@isu.isunet.edu", and (un)subscription requests of the form
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(THENET), or space-REQUEST@isu.isunet.edu (Internet).
----------------------------------------------------------------------
Date: Sat, 27 Feb 93 10:39:09 GMT
From: Dean Adams <dnadams@nyx.cs.du.edu>
Subject: Aurora (rumors)
Newsgroups: sci.space
PHARABOD@FRCPN11.IN2P3.FR writes:
>Suppose Aurora wants to spy on some installation deep inside a big
>country. Suppose it flies over the border at 30,000 ft up.
Well, you can stop supposing right there! That is not a credible suggestion.
Early U-2 flights were done at 65,000 feet, and SR-71 missions were at around
85,000 feet. Aurora would very likely be flying at operational altitudes of
over 100,000 feet.
>Before it has penetrated 100 miles inside, the whole country may
>be on alert.
Then why suggest such a thing?
>But maybe Aurora has been designed to spy on little countries like
>Panama...
No, the TR-1 could perform that mission quite effectively.
>However, in that case, the noise would tell the inhabitants
>they *have been* spied on.
Not if they can't hear it.
>but Aurora should keep rather far off the borders.
That would depend on who's borders we are talking about, and if it was
too far, then it would not be possible to collect the needed data.
>Why is it extremely audible in the Los Angeles area?
Because it is on a LANDING profile. It comes in off the Pacific,
decelerating and reducing altitude for a landing in the Nevada desert.
>Does it fly at rather low altitude?
Certainly not anywhere near the recon target area.
>If yes, can it only fly at hypersonic speed ?
No... it has to take off and land you know.
>(it should never land !)
Huh?
>Does Aurora hate Los Angeles ?
Hopefully I can ask it sometime.
------------------------------
Date: Mon, 01 Mar 93 17:03:39 MET
From: PHARABOD@FRCPN11.IN2P3.FR
Subject: Aurora (rumors)
Dean Adams writes (26 Feb 93 04:42:33 GMT):
>PHARABOD@FRCPN11.IN2P3.FR writes:
>>The plane must have been flying at an altitude of at least 10 kilometres,
>>because it was not picked up on radar.
I myself did not say that, I was quoting "New Scientist".
>Since when does radar stop at FL 300? ATC radar should cover that
>territory quite well.
True (from the little I know).
> Also, Aurora could very likely incorporate
>stealth characteristics.
Maybe, but it seems difficult to make hypersonic planes really stealth.
According to Kenneth W. Foulke in article CONTROLLING RADAR SIGNATURE
(Aerospace America, August 1992):
"... all-aspect low RCS is not very compatible with supersonic design.
Trades must be made between shaping for radar signature and for
aerodynamic purposes for optimum design to be achieved".
> That is still no reason to go blaming
>every strange "explosion" on Aurora.
The Dutch scientists said it was an unknown supersonic plane. You say
it was not Aurora. Maybe the Russians ?
J. Pharabod
------------------------------
Date: Mon, 01 Mar 93 17:33:42 MET
From: PHARABOD@FRCPN11.IN2P3.FR
Subject: Aurora (rumors)
>Sorry, folks but I'll have to throw some cold water on this one. The
>origin of this report is a very brief article which appeared late last
>summer in AvLeak (AW&ST, Aug. 24, p. 24). The report was by a UAL 747
>eastbound out of LAX which had a head-on encounter with something in the
>vicinity of Edwards AFB. (Paul Keller, 26 Feb 1993 13:51:58 GMT)
They wrote George, not Edwards.
>Although I do not have that issue on my desk right now, the gist of that
>report was that it appeared to be some sort of supersonic drone which
>got away. I believe it was described as "F-16 sized, or smaller."
"The several-second sighting gave the crew the impression that the
other aircraft was a lifting-body configuration, and they described
it as looking like the forward fuselage of a Lockheed SR-71 -
without wings but with a tail of sorts. They estimated the size
as similar to an F-16 (49.3-ft. length) and said it had a dark color
with a shiny spot on top that may have just been sun glint. The
closure rate was 2-3 times normal, and the crew assumed the other
aircraft was supersonic".
Yes, this does not look like the "classical" description of Aurora.
Too small, in particular. This is one of the reasons why I find
these August 24 AW&ST articles not very serious.
J. Pharabod
------------------------------
Date: Mon, 01 Mar 93 18:14:42 MET
From: PHARABOD@FRCPN11.IN2P3.FR
Subject: Aurora (rumors)
(Preliminary remark: I receive only the space digest, therefore I often
get your mails a couple of days after they have been posted)
>>Also, it has a strange habit of shouting "Hi folks, I'm coming to
>>spy on you !". (J. Pharabod)
>More on the order of "Bye, I have just left the neighborhood."
>(By the time you hear the sound, the aircraft is gone.)
>(Steve Hix, 25 Feb 93 23:41:56 GMT)
Suppose Aurora wants to spy on some installation deep inside a big
country. Suppose it flies over the border at 30,000 ft up. Before
it has penetrated 100 miles inside, the whole country may be on
alert. Radio waves, phone calls, e-mail go much faster than any
kind of Aurora.
But maybe Aurora has been designed to spy on little countries like
Panama... However, in that case, the noise would tell the inhabitants
they *have been* spied on.
J. Pharabod
P.S. Also, please consider the following posting from Peter Scott
(24 Feb 1993 16:27:39 GMT):
>I think I read once that the Soviet Union (when there was one) had
>installed auditory sensors at key places along their borders to
>listen for the sound of an otherwise stealthy plane entering their
>country at low altitude. Can anyone confirm this one way or the other?
------------------------------
Date: 27 Feb 93 20:12:32 GMT
From: Ron Baalke <baalke@kelvin.jpl.nasa.gov>
Subject: Cheap Mars Rocks (was Re: Moon Dust For Sale)
Newsgroups: sci.space,sci.astro,alt.sci.planetary
In article <93008.095402K3032E0@ALIJKU11.BITNET>, <K3032E0@ALIJKU11.BITNET> writes...
>Why buy 1gramm moondust for about $4000.- (or 1 pound for $2'000'000)
>when I bought 4g Mars rock for $350.- two years ago???
>
The going rate for the Zagami meteorite is still about $100 per gram and
that is the lowest of all the SNC meteorites. The Nahkla meteorite is going
for something like $200 to $300 per gram. The price on the Chassigny is
sky high because there are so few pieces that have left France. The
two Chassigny pieces I've seen were only 8g and 13g, but were selling for
$24,000 and $39,000, respectively.
>Taking all the known SNC meteorites known, there are hardly more than 100pounds
>of mars rock available. Thus, $100,000 for a two inch tape of moondust is quite
>a high price|| I think I'll wait until a *large* lunar meteorite drops down
>somwhere...
The moon dust hasn't been sold yet, and I think it will go for well under
the $100,000.
___ _____ ___
/_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov
| | | | __ \ /| | | | Jet Propulsion Lab |
___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Choose a job you love, and
/___| | | | ___/ | |/__ /| Pasadena, CA 91109 | you'll never have to work
|_____|/ |_|/ |_____|/ | a day in your life.
------------------------------
Date: Sat, 27 Feb 1993 16:55:54 GMT
From: Frank Crary <fcrary@ucsu.Colorado.EDU>
Subject: Hopkins Leaks (was Re: Blimps)
Newsgroups: sci.space
In article <C32uDo.KtE@unccsun.uncc.edu> jechilde@unccsun.uncc.edu (John E Childers) writes:
>Have you considered using a glider at Jupiter? With all that convection
>soaring might be practical. The control system would be much more
>complex than for a ballon but a glider would be realitively strong compaired
>to a ballon...
Gliders have been looked at, but they suffer from the Jovian
gravity (~2.5g) much more than balloons. Unless you have a very
good reason to travel rapidly, gliders aren't really worth it...
Frank Crary
CU Boulder
------------------------------
Date: Sat, 27 Feb 1993 10:31:23 GMT
From: David Woodsworth <David_Woodsworth@mindlink.bc.ca>
Subject: Human Distance Record:Apollo 13
Newsgroups: sci.space
The 1990 Guinness Book of Records has this to say:
Most isolated - The farthest any human has been removed from his nearest
living fellow man is 3596.4 km (2233.2 miles) in the case of the Command
Service Module pilot Alfred M. Worden on the US Apollo 15 lunar mission of 30
Jul - 1 Aug 1971.
--
Why not go mad?
david_woodsworth@mindlink.bc.ca
------------------------------
Date: Sat, 27 Feb 1993 19:56:21 GMT
From: "Phil G. Fraering" <pgf@srl03.cacs.usl.edu>
Subject: Instead of Fred.. ETCo?
Newsgroups: sci.space
WELLS <WELLS@CTSD2.JSC.NASA.GOV> writes:
>This was studied in the '85 to '86 time frame. The concept was to strap
>a large number of ET's together to make a platform for an SPS or Solar
>Power Satellite. The ET's were to be taken to orbit while attached to
>the orbiter, final kick to be accomplished using a small strap on
>propulsion module on the aft end of the ET that burned its residual
>prop. Problems with the approach were numerous and included quantity and
>mixture ratio uncertainties of residual H2 and O2, dealing with
>propellant pressure and phase uncertainties, how to tie in to the ET
>both structural and fluid, control, and the "crumby" tank itself (the
>tank insulation would crumble and spall off after a period on orbit).
>...fun to dream, though.
"We looked at in once for one application, deceided it wouldn't
work, and don't have to look at anything like it for any application
ever again."
Lots of people have looked at many ways of implementing an ET space
station, and they reach conclusions much better than described above.
--
Phil Fraering |"...drag them, kicking and screaming,
pgf@srl02.cacs.usl.edu|into the Century of the Fruitbat." - Terry Pratchett,
_Reaper Man_
------------------------------
Date: 27 Feb 1993 10:29:45 -0500
From: Pat <prb@access.digex.com>
Subject: Reliable Source says Freedom Dead, Freedom II to be developed
Newsgroups: sci.space
There you go dennis, you hit on what I was thinking.
STick a module onto the side hatch of an ET.
SUre, the RMS or Candaarm, works like a devil to mount the ET to the truss,
and sure you don't have a lot of meteor protection, but Cheap
Low quality space I am sure will have lots of uses.
Keep the Freedom style heavy modules for core elements, but make the scientists
work in the "Ghetto" space. live in comfort, work in hell.
sounds like my job:-)
pat
------------------------------
Date: Mon, 1 Mar 93 08:20:39 CST
From: a20461@itesocci.gdl.iteso.mx (Cruz Lugo Eric De La)
Subject: Request for info about Ecuations and constants
Saludos desde Guadalajara Jal., Mexico!!!!
i need some information about ecuations, constants and planetary data
im developing a solar sistem simulation in Pascal, and i need the info
for calculate Planet's R.A. and Declination.
Any help will be greatly apreciated, Tanks in advance...
Eric De La cruz Lugo a20461@iteso <-----bitnet
a20461@itesocci.gdl.iteso.mx <-----Internet
This is a job for...nobody, look in the sky is, is...nothing SUPERMAN is
DEAD.
------------------------------
Date: Mon, 1 Mar 1993 17:51:54 GMT
From: Nick Haines <nickh@CS.CMU.EDU>
Subject: SOLAR gravity assist? Yup.
Newsgroups: sci.space
In article <fnalf.1993Feb25.194845.1>, Bill Higgins posts an
interesting article about getting a gravity-assist from the sun by
skimming its surface, using the slingshot effect and the fact that the
sun is (of course) in orbit around the system's centre of mass.
Unfortunately the maximum possible delta-v one can get from such a
manoever (calculated as change in velocity at infinity) is twice the
sun's orbital v, or about 25 m/s. You're going to do _much_ better
using the Oberth gravity-assist, doing a burn at perihelion. If you
can skim the surface of the sun, your specific PE there is 2e11 J/kg.
If you've fallen in parabolically (and any orbit you can get to out
here in the real solar system is going to be close to parabolic when
you get that close to the sun) then your KE is the same (i.e. you're
moving at >630 km/sec -- whoooo). Add 4 km/s delta-v in a burn and
when you get out to infinity (or near-enough, i.e. any planetary
distance) you're doing a cool 71 km/s. Where do you want to go?
Even if you don't get _that_ close to the sun this works really well.
If your parabolic perihelion is at Mercury's orbit (5e10 m, for the
sake of argument) then you're moving at 72 km/s, so a 4 km/s burn gets
you 24 km/s out at infinity. Which is plenty for a not-particularly
difficult engineering task (Mariner went that close to the sun without
too much trouble).
This adds another interesting question to Bill's list, which I'll tack
onto the end of my set of answers:
1. [...], can you follow a solar slingshot with a Jovian slingshot
and get even more energy? Can you somehow repeat this trick for
endless energy pumping, or show that this is impossible?
The velocity available from a solar slingshot is so tiny as to be not
worth the bother. If you do an Oberth gravity assist then the delta-v
you get is so large that you're not going to need a Jupiter assist.
2. How much help do you get when you throw in Saturn? Rs= 1.427E9 km,
Ms= 5.688E26 kg, Msun=3498.5 Msaturn.
See above; this is inconsequential.
3. [Library question:] What is the uncertainty in the solar radius?
What is the density profile of the solar atmosphere? How did people
measure these things?
The `solar radius' usually quoted is that of the photosphere (i.e. the
bit at about 5000K which emits the visible light of the sun). It's
reasonably stable (I guess +/- 10000 km), not counting flares (which
can rise several solar radii from the surface, but are sufficiently
unusual as to be not terribly dangerous; we're only going to be that
close to the sun for about an hour). How are they measured? From
photographs.
4. How *do* you engineer a spacecraft to go arbitrarily close to the
Sun? (Spare me Brin's "refrigerator laser," I already know about it
and his ship uses magic technology for its other systems.)
You get it damn cold when it's well away from the sun, you put
carbon-carbon (or similar) materials all around it, and you zip in and
out in hours. As soon as you're moving away from the sun you deploy
big cooling sails. It's still very hard, and I would guess infeasible
with present technology. A much less controllable method is to wrap it
in about a km of ice; if you can control the ablation then this gives
you your perihelion burn for free. If you can't control it then you
get dumped into the sun.
5. [...] What is its optimal path if you take helioaerodynamics
into account?
Ask a grad student. Now my question:
6. If we _do_ skim the sun, at 600+ km/sec, how precisely do we
need to control the timing and direction of our perihelion burn?
Nick Haines nickh@cmu.edu
------------------------------
Date: 27 Feb 1993 18:49 UT
From: Ron Baalke <baalke@kelvin.jpl.nasa.gov>
Subject: Space Calendar - 02/27/93
Newsgroups: sci.space,sci.astro,alt.sci.planetary
Here's the latest Space Calendar. The Space Calendar is updated monthly
and the latest copy is available at ames.arc.nasa.gov in the /pub/SPACE/FAQ
directory as space.calendar. Please send any updates or corrections
to Ron Baalke (baalke@kelvin.jpl.nasa.gov). Note that launch dates are
subject to change.
The following people made contributions to this month's calendar:
o Jeff Bulf - Pioneer Venus Orbiter 15th Anniversary of launch
(05/20/78)
o Rich Kolker - Updated DC-X Test Flight Date (4/23/93)
o Gero Rupprecht - Wilhelm Herschel's Birthday (Nov. 15, 1738)
o Mike Hamilton - Updated SeaWIFS Launch Date (10/1/93)
o Jeff Bloch - Updated ALEXIS Launch Date (4/12/93)
=========================
SPACE CALENDAR
February 27,1993
=========================
* indicates change from last month's calendar
February 1993
Feb 01 - 35th Anniversary, Explorer 1 Launch (1st U.S. Satellite)
Feb 08 - Mars Observer, 2nd Trajectory Correction Maneuver (TCM-2)
* Feb 08 - SCD-1 Pegasus Launch (Brazil)
Feb 18 - Jules Verne's 165th Birthday
Feb 19 - Copernicus' 520th Birthday
* Feb 19 - Consort 6 Starfire Launch
* Feb 19 - Astro-D M3S-2 Launch (USA/Japan)
March 1993
Mar ?? - DFH-3 Long March 2E Launch (China)
Mar ?? - GPS/SEDS-1 Delta II Launch
Mar 01 - Ulysses, 3rd Opposition
* Mar 09 - Galileo, Trajectory Correction Maneuver #19 (TCM-19)
Mar 11 - UHF-1 Atlas Launch
* Mar 14 - STS-55, Columbia, Spacelab Germany (SL-D2)
Mar 18 - Mars Observer, 3rd Trajectory Correction Maneuver (TCM-3)
* Mar 21 - Gravity Wave experiment involving Galileo, Mars Obsever and
Ulysses spacecraft begins
* Mar 23 - Progress Launch (Soviet)
Mar 31 - Commercial Experiment Trasporter (Comet) Conestoga Launch
April 1993
* Apr ?? - Galaxy 4 Ariane Launch
* Apr ?? - Hispasat 1B & Insat 2B Ariane Launch
* Apr 01 - STS-56, Discovery, Atmospheric Lab for Applications and Science
(ATLAS-2)
Apr 06 - 20th Anniversary, Pioneer 11 Launch (Jupiter & Saturn Flyby Mission)
* Apr 12 - ALEXIS Pegasus Launch
Apr 19 - Venus/Moon Occultation, Visible from North America
Apr 22 - Lyrid Meteor Shower (Maximum: 03:00 UT, Solar Longitude 32.1 degrees)
* Apr 23 - First Test Flight of the DC-X (Unmanned)
Apr 28 - STS-57, Endeavour, European Retrievable Carrier (EURECA-1R)
May 1993
May ?? - Advanced Photovoltaic Electronics Experiment (APEX) Pegasus Launch
May ?? - Radcal Scout Launch
May ?? - Astra 1C Ariane Launch
May ?? - GPS/PMQ Delta II Launch
May 04 - Galileo Enters Asteroid Belt Again
May 04 - Eta Aquarid Meteor Shower (Maximum: 21:00 UT, Solar Lon: 44.5 deg)
* May 20 - 15th Anniversary, Pioneer Venus Orbiter Launch
May 21 - Partial Solar Eclipse, Visible from North America & Northern Europe
* May 25 - Magellan, Aerobraking Begins?
June 1993
Jun ?? - Temisat Meteor 2 Launch
Jun ?? - UHF-2 Atlas Launch
Jun ?? - NOAA-I Atlas Launch
Jun 04 - Lunar Eclipse, Visible from North America
Jun 14 - Sakigake, 2nd Earth Flyby (Japan)
Jun 22 - 15th Anniversary of Charon Discovery (Pluto's Moon) by Christy
* Jun 30 - STS-51, Discovery, Advanced Communications Technology Satellite
July 1993
Jul ?? - MSTI-II Scout Launch
Jul 01 - Soyuz Launch (Soviet)
Jul 08 - Soyuz Launch (Soviet)
Jul 14 - Soyuz TM-16 Landing (Soviet)
Jul 21 - Soyuz TM-17 Landing (Soviet)
Jul 28 - S. Delta Aquarid Meteor Shower (Maximum: 19:00 UT,
Solar Longitude 125.8 degrees)
Jul 29 - NASA's 35th Birthday
August 1993
Aug ?? - ETS-VI (Engineering Test Satellite) H2 Launch (Japan)
Aug ?? - GEOS-J Launch
Aug ?? - Landsat 6 Launch
Aug ?? - ORBCOM FDM Pegasus Launch
Aug 09 - Mars Observer, 4th Trajectory Correction Maneuver (TCM-4)
Aug 12 - N. Delta Aquarids Meteor Shower (Maximum: 07:00 UT,
Solar Longitude 139.7 degrees)
Aug 12 - Perseid Meteor Shower (Maximum: 15:00 UT,
Solar Longitude 140.1 degrees)
Aug 24 - Mars Observer, Mars Orbit Insertion (MOI)
Aug 25 - STS-58, Columbia, Spacelab Life Sciences (SLS-2)
Aug 28 - Galileo, Asteroid Ida Flyby
September 1993
Sep ?? - SPOT-3 Ariane Launch
Sep ?? - Tubsat Launch
Sep ?? - Seastar Pegasus Launch
Sep ?? - EPOT-3/ASAP-4 Ariane Launch
October 1993
Oct ?? - Intelsat 7 F1 Ariane Launch
Oct ?? - SLV-1 Pegasus Launch
Oct ?? - Telstar 4 Atlas Launch
* Oct 01 - SeaWIFS Launch
Oct 22 - Orionid Meteor Shower (Maximum: 00:00 UT,
Solar Longitude 208.7 degrees)
November 1993
Nov ?? - Solidaridad/MOP-3 Ariane Launch
Nov 03 - 20th Anniversary, Mariner 10 Launch (Mercury & Venus Flyby Mission)
Nov 03 - S. Taurid Meteor Shower
Nov 04 - Galileo Exits Asteroid Belt
Nov 06 - Mercury Transits Across the Sun, Visible from Asia, Australia, and
the South Pacific
Nov 10 - STS-60, Discovery, SPACEHAB-2
Nov 13 - Partial Solar Eclipse, Visible from Southern Hemisphere
* Nov 15 - Wilhelm Herschel's 255th Birthday
Nov 17 - Leonids Meteor Shower (Maximum: 13:00 UT,
Solar Longitude 235.3 degrees)
Nov 28-29 - Total Lunar Eclipse, Visible from North America & South America
December 1993
* Dec ?? - Mars Observer, Mapping Begins
Dec ?? - GOES-I Atlas Launch
Dec ?? - NATO 4B Delta Launch
Dec ?? - TOMS Pegasus Launch
Dec ?? - DirectTv 1 & Thiacom 1 Ariane Launch
Dec ?? - ISTP Wind Delta-2 Launch
Dec ?? - STEP-2 Pegasus Launch
Dec 01 - Mars Observer, Mapping Orbit Established
Dec 02 - STS-61, Endeavour, Hubble Space Telescope Repair
Dec 04 - SPEKTR-R Launch (Soviet)
Dec 05 - 20 Anniversary, Pioneer 10 Launch (Jupiter Flyby Mission)
Dec 08 - Mars Observer, Mars Equinox
Dec 14 - Geminids Meteor Shower (Maximum: 00:00 UT,
Solar Longitude 262.1 degrees)
Dec 20 - Mars Observer, Solar Conjunction
Dec 23 - Ursids Meteor Shower (Maximum: 01:00 UT,
Solar Longitude 271.3 degrees)
January 1994
Jan 02 - Mars Observer, End of Solar Conjunction
Jan 24 - Clementine Titan IIG Launch (Lunar Orbiter, Asteroid Flyby Mission)
February 1994
* Feb ?? - SFU Launch
* Feb ?? - Muses-B Launch (Japan)
* Feb ?? - GMS-5 Launch
* Feb 05 - 20th Anniversary, Mariner 10 Venus Flyby
* Feb 08 - STS-62, Columbia, U.S. Microgravity Payload (USMP-2)
* Feb 15 - Galileo's 430th Birthday
* Feb 21 - Clementine, Lunar Orbit Insertion
* Feb 25 - 25th Anniversary, Mariner 6 Launch
___ _____ ___
/_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov
| | | | __ \ /| | | | Jet Propulsion Lab |
___| | | | |__) |/ | | |__ M/S 525-3684 Telos | If you don't stand for
/___| | | | ___/ | |/__ /| Pasadena, CA 91109 | something, you'll fall
|_____|/ |_|/ |_____|/ | for anything.
------------------------------
Date: Mon, 1 Mar 93 14:53:10 EET
From: flb@flb.optiplan.fi (F.Baube x554)
Subject: Spy Sats
Dean Adams <dnadams@nyx.cs.du.edu>
> The space based ELINT systems [..]can deploy LARGE antenna arrays
> and ferret out all kinds of interesting signals...
how large is LARGE ?
--
* Fred Baube GU/MSFS * We live in only one small room of the
* Optiplan O.Y. * enormous house of our consciousness
* baube@optiplan.fi * -- William James
* #include <disclaimer.h> * nymphs vex, beg quick fjord waltz
------------------------------
Date: Sat, 27 Feb 1993 14:51:26 GMT
From: "Allen W. Sherzer" <aws@iti.org>
Subject: SSF Resupply (Was Re: Nobody cares about Fred?)
Newsgroups: sci.space
In article <STEINLY.93Feb26144040@topaz.ucsc.edu> steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes:
> Now go out and buy a brick. Wrap it in paper and see if you can find
> a company who will ship it to me for free. If they balk, explain to
> them how they have deadhead space and so it doesn't matter. If you
> manage to do this, I'll accept your arguement.
>Well, Allen, I could ship you a brick FedEx (or USPO express) (COD of
>course ;-)
Then you would be violating the rules of the experiment. Dennis is asserting
that we shouldn't worry about the excess weight since the marginal cost is
almost nothing. As proof he cliams that shipping comanies work the same
way. If this where true, then he would have no problem finding companies
willing to ship a brick to me for free.
>- you will be rather astonished to find that the charge for
>shipping the brick will not be the cost of the truck+flight from here
>to there, rather they'll charge a marginal cost
No, they will charge much more than the marginal cost. The marginal cost
is simply the cost of producing (or delivering) one more item. For our
brick it would be the cost of the fuel needed to move the extra mass,
the extra wear on the truck, and the time of the people who load and
unload the brick.
It doesn't include overhead costs, amortization of vehicles, profit, or
anything else. Any company who only charges their customers the marginal
cost will soon find itself out of buisness. Even standy fare on an
airliner is more than marginal cost.
> If we re-fueled automatically and left the thrusters in place we would
> go from ~50 shuttle flights costing $25 billion and go to ~50 Delta
> flights costing less than $2 billion. A savings of over $23 billion.
>Allen, what is the development cost of learning how to do
>automatic refuelling and over how many flights will you amortise it?
I suppose we could buy it today from the Russians. But then Doug would
get all pissed off and call me a commie again.
So I called up a friend at one of the NASA centers for the commercialization
of space (another place where NASA is doing a good job Dennis). He is the
deputy program manager of an effort to build an automatic docking system
foe satellite refueling. He put the cost well under $100M.
> Do you propose flying fewer shuttle flights without the
>resupply (in which case the marginal cost on the remaining flights
>increase) or should NASA redirect those flights to another purpose?
I propose the Shuttle fly whatever paying customers it can find. If
if that means station logistics, fine. However, if cheaper ways can
be found I as a taxpayer and somebody very interested in the development
of space want to see them used.
>Or should they simply fire 20,000 support staff - in which case what
>is the cost of severance (including any welfare support to the
>government)?
Well, I think it would be a good idea to make space cheap. That way
maybe those people can find productive work in a growing space
economy rather than live off of government aerospace welfare.
Would you have told Henry Ford to not build his car because of the
thousands of buggy whip makers who would be out of a job?
> You make good points, but your accounting methods are, shall
>we say systematically skewed.
They're not as good as they would be is somebody paid me to do them (my
cost estimates for the projects I work on is pretty good).
But I usually find that they're good enough since the savings is
much larger than the likely error in my estimates. I could be off
by a factor of five for refueling above, for example, and it would
still be a good idea.
Allen
--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves |
| aws@iti.org | nothing undone" |
+----------------------108 DAYS TO FIRST FLIGHT OF DCX----------------------+
------------------------------
Date: 27 Feb 1993 10:16:35 -0500
From: Pat <prb@access.digex.com>
Subject: SSF Resupply (Was Re: Nobody cares about Fred?)
Newsgroups: sci.space
In article <STEINLY.93Feb26144040@topaz.ucsc.edu> steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes:
|In article <1993Feb26.205533.6505@iti.org> aws@iti.org (Allen W. Sherzer) writes:
|
|Well, Allen, I could ship you a brick FedEx (or USPO express) (COD of
|course ;-) - you will be rather astonished to find that the charge for
|shipping the brick will not be the cost of the truck+flight from here
Allen was arguing that you can't get deadhead space free from anyone.
True. Most drivers operate under the "Gas, Grass or Ass, No-one rides
for free" policy. Steinn, to argue marginal cost is irrelevant to allens argument.
Wingo was trying to claim that thrusters fly for free. Allen pointed
out that was a crock. You then come up with some argument on the
cost being the operating cost divided by payload. Sadly, that's
allen's point, too. The cost of dragging thrusters to orbit does
cost 10,000/pound under any rational accounting scheme. any claims to
the contrary is a fiction.
|
|
| Except that with automated refueling we can use $35 million Delta's
| instead of half a billion $$ shuttle flights for refueling.
|
| If we re-fueled automatically and left the thrusters in place we would
| go from ~50 shuttle flights costing $25 billion and go to ~50 Delta
| flights costing less than $2 billion. A savings of over $23 billion.
|
|Allen, what is the development cost of learning how to do
|automatic refuelling and over how many flights will you amortise it?
I believe allen did those numbers. He proposed that at 8% rate of return
and 4 Billion up front in engineering, you payback in 4 years.
| Do you propose flying fewer shuttle flights without the
|resupply (in which case the marginal cost on the remaining flights
|increase) or should NASA redirect those flights to another purpose?
|Or should they simply fire 20,000 support staff - in which case what
|is the cost of severance (including any welfare support to the
|government)?
Neither of these questions are relevant to the Freedom PMO. THey are
a problem for Johnson, kennedy and HQ. IT is the job of Reston to
do the most with the least dollars. It's HQ's job to figure out how to
rebalance missions. What if we signed a deal on 5 energiyas. suddenly
26 shuttle missions go by the way. Is that restons fault? of course not.
The assumption is HQ will either direct new shuttle missions or
reduce the program size. simple enough and nobody's problem
but theirs.
>
> You make good points, but your accounting methods are, shall
>we say systematically skewed.
>
Allen makes good points, and given i have a masters in Business and
Public administration, I would say in keeping with accepted practice.
Politically naive, oftentimes, but acceptable.
I would challenge you steinn to find any textbook which dictates
that allen is wrong.
------------------------------
Date: Sat, 27 Feb 1993 15:01:55 GMT
From: "Allen W. Sherzer" <aws@iti.org>
Subject: SSTO Estimates (was Re: Refueling in orbit)
Newsgroups: sci.space
In article <STEINLY.93Feb26151749@topaz.ucsc.edu> steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes:
> SSTO fans would do well to re-read the history of some
>modern launchers, including the original Shuttle concept and how
>it evolved.
I have. I note with pleasure that SDIO seems to have as well and has
learned from those mistakes.
>Might make some a little less firm in their cost estimates
You will note that my detailed cost estimates for SSTO which I
posted a while back had costs about twice other estimates. But
with an SSTO with its emphasis on rapid turnaround, the costs
come down fast as the market grows.
Now it may be that the turnaround goals can't be met yet. But
SSTO is still a good idea because even if it fails it will tell
us exactly what we need to do to make it work and will suggest
solutions to those problems.
>and a little less ready to cut other transport systems before the
>SSTOs have demonstrated operational ability..
Nobody is talking about cutting all transport system, only those
which aren't cost effective and can only survive via wasteful
government subsidy.
>in particular Allen
>might be astonished to realise that some of his DC claims look
>like they were cut out from a NASA report circa 1971-1974 providing
>STS claims ;-)
The problem with this arguement is it doesn't address just why
Shuttle failed and what is different this time. This arguement amounts
to a proof that space will never be cheap for no other reason than
that the Shuttle failed. Without more analysis it's not a very good
arguement.
Allen
--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves |
| aws@iti.org | nothing undone" |
+----------------------108 DAYS TO FIRST FLIGHT OF DCX----------------------+
------------------------------
Date: Mon, 1 Mar 93 19:22:09 -0800
From: d7724502@dec2.ncku.edu.tw
UNSUB SPACE
------------------------------
End of Space Digest Volume 16 : Issue 246
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