Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V15_5/V15NO524.TXT

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Date: Wed,  9 Dec 92 05:07:40
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #524
To: Space Digest Readers
Precedence: bulk


Space Digest                Wed,  9 Dec 92       Volume 15 : Issue 524

Today's Topics:
              absolutely, positively overnight (2 msgs)
                        Another Orbit Question
           Apollo 10 LM (was Re: pre-fire Apollo schedule)
                   Clinton/Gore & Space exploration
                             Earth Movie
                       Galileo Cruises By Earth
                              Goldin...
                    NASA software standard needed
                           Orbit Question?
                     Potential uses for the DC-X
                               Rush...
         Rush Limbaugh says problems with HST is a DoD hoax!
                         Shuttle replacement
                             space policy
           Terminal Velocity of DCX? (was Re: Shuttle ...)
                    US weather satellite question
                        US Weather Satellites

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Date: 8 Dec 92 17:34:00 GMT
From: [e-mail]
Subject: absolutely, positively overnight
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Pat) writes...
>In article <[e-mail]> [e-mail] (Josh 'K' Hopkins) writes:
>>[e-mail] (Simon E. Booth) writes:
>>
[stuff deleted]
>ccording to Wingo, the Saturn 1 was developed under an Army spec
>to be able to rapid deliver 800 airborne troops anywhere in the world
>in 20 minutes.

[stuff deleted]

>ADennis,  do you wish to elaborate on this,  or was this an elaborate
>attempt to pull my leg that day...

I read about this a few year ago and confirmed it with Father Medaris (Formerly
General Bruce Medaris, Von Braun's Early Boss at the ABMA. I forget whether
I read this in Medaris's book "Count Down to Decision" or in the Book "The
Rocket Scientists". Anyway this was the rational for building the Saturn 1 as
an Army project. The first Saturn I was test fired in 1959 and the first flight
of the bird was in 1963, BEFORE the Gemini missions. The Saturn V first
stage, the F1 was also originally conceived as an Army engine, also by the
Von Braun Team.

I think the troop transporter rational was how they were able to get funding
for the Saturn 1 booster before the Kennedy era. Both of the books I mentioned
are great reading, Although Medaris's book will be pretty hard to find.

Dennis, University of Alabama in Huntsville

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

Date: 8 Dec 92 20:03:54 GMT
From: Henry Spencer <[e-mail]>
Subject: absolutely, positively overnight
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>>ccording to Wingo, the Saturn 1 was developed under an Army spec
>>to be able to rapid deliver 800 airborne troops anywhere in the world
>>in 20 minutes.
>
>I read about this a few year ago and confirmed it with Father Medaris ...
>... this was the rational for building the Saturn 1 as
>an Army project.

Except that it wasn't an Army project, actually.  The startup funding
came from ARPA in 1958, after early design studies in response to somewhat
vague DoD requirements.  Originally the contract (ARPA funding the work
at ABMA [the Army Ballistic Missile Agency, i.e. von Braun & co]) was
only for a ground test of the 8-engine cluster; this is why the tanks
were built by clustering existing tankage, to save time and money on
a project that wasn't originally meant for flight.  Late in 1958 ARPA
enlarged the contract to cover flight demonstrations, still with only
one stage.

As of 13 Oct 1958, ABMA listed its customers as (1) ARPA (as a generic
carrier for R&D of "offensive and defensive space weapons"), (2) the
three military services (navsats for the Navy; spysats, comsats, and
weather satellites for Army and Air Force; "support" for Air Force
manned spaceflight; "surface-to-surface supply" for the Army),
(3) NASA (support of space missions, plus as a possible testbed for
the F-1 and similar engines), and (4) other customers, possibly
including the UN and private companies.  In that order.

ARPA's number one priority, actually, appears to have been geostationary
comsats, although they weren't identified quite so explicitly.  It also
thought of the Saturn as a general-purpose heavy lifter.

(Reference:  "Stages to Saturn", NASA SP-4206, pages 26-38.)

In summer 1959, ARPA funding for Saturn ran into big trouble, as Herbert
York (DoD Research & Engineering head) decided that there was no valid
military mission for it, citing a belief that boosters based on existing
ICBMs were a better method for launching comsats.  York was eventually
talked into continuing support temporarily, on condition that work be
started on moving ABMA and Saturn to NASA, since they were the only ones
who seemed to have real need for Saturn.

>The first Saturn I was test fired in 1959 and the first flight
>of the bird was in 1963...

The first Saturn I flew on 27 Oct 1961, actually.

>... the F1 was also originally conceived as an Army engine, also by the
>Von Braun Team.

Sorry, dead wrong here.  The F-1 originated with a USAF program in 1955,
arrived at NASA in 1958 when USAF spaceflight was transferred to NASA,
and became a full-scale development effort with a major NASA contract
in 1959.
--
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: 8 Dec 92 20:44:02 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Another Orbit Question
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>
>Beep beep beep.  Innumeracy alert. :-)

Blush. You're right of course.

Gary

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

Date: Tue, 8 Dec 1992 19:27:00 GMT
From: Henry Spencer <[e-mail]>
Subject: Apollo 10 LM (was Re: pre-fire Apollo schedule)
Newsgroups: sci.space.shuttle,sci.space

In article <[e-mail]> [e-mail] (Bill Higgins-- Beam Jockey) writes:
>> Apollo 11
>> (July 1969) in fact had the very first LM that was light enough to fly
>> a complete lunar landing and takeoff...
>
>All of us watching the Apollo 10 crew circle the Moon, detatch the
>Lunar Module, and descend to a low altitude were thinking, "What if
>they land it, and jump the gun on Apollo 11?  Must be tempting!"
>
>Henry, you imply that Apollo 10's LM couldn't actually land and
>return.  Can you elaborate?  This is the first I've heard of this.

I no longer recall exactly where I saw this mentioned, and it doesn't get
much play in the various histories.  The dress-rehearsal mission was thought
justified for several other reasons.  Michael Collins's "Liftoff", however,
talks about it.  He says that the Apollo 10 LM *probably* could have
flown a lunar landing if some fuel had been offloaded to lighten it, but
the margins would have been slim and hard to predict.  It would probably
have been tried if the end-of-1969 deadline had been imminent, but as it
was, the risk was unnecessary.  The Apollo 11 LM would be lighter, and
there was still time.  (NASA was ready to fly 11, 12, and 13 before the
end of 1969 if necessary; with 11 successful, 12 was postponed to the
original 13 launch window to give the KSC crews a breather and give more
time for science assessment of the 11 samples.)

So, as actually flown the Apollo 10 LM was indeed a little too heavy.
--
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: Tue, 08 Dec 92 22:15:30 EST
From: Tom <[e-mail]>
Subject: Clinton/Gore & Space exploration

Simon sez;
>>... While I didn't vote for Clinton/Gore, I won't
>>write off our space program yet.

Carlos sez;
>...  Gore is very pro 'environmental' technology so yes EOS will
>be alive.  But read their policy statement regarding space (posted here before
>the election)

>*Biggest focus- Mission to planet Earth

>*The only reason they mention to keep Freedom is because it creates jobs.
>Whether you think Freedom will or will not generate good science, keeping it
>only for the jobs is a lousy way to run a space program.

It's a lousy way to run anything!  Imagine applying the same logic to
the Farm Problem:  "We found that recent initiatives by John Deere and
International Harvester have severly affected the job market in
agriculture...:-)"

>*Moon, Mars, and the Space Exploration Initiative, are mentioned as worthy
>goals... when we have the money.  In other words not for a long, long time.

I'd have to say this is just fine, as I think the most useful goals are to
find the resources that would make exploration/exploitation cheaper.  I
know the goals on Mars include resources, but between the fact that it's
supposed to be manned, and NASA's history of doing high-profile, national
prestige-motivated missions, I think there are more cost effective ways of
doing the actual science that we all want done.  Like CRAF (RIP ;-(

Mars ain't goin' anywhere, and any water on the moon has lasted a few
billion years, so waiting long enough to learn of any resources that would
make exploration/colonization easier for actual humans won't change the
situation or damage the knowledge-to-be.

Imagine how easy a Mars mission would be if we spent the last twenty
years looking for easily accessible minerals and volatiles in the
near-earth Asteroids or comets (assuming we decided to use them).

As much as the Apollo mission did for our culture and knowledge, I still
find myself thinking that it was done primarily for National Prestige.
And I can see this same goal in much of what NASA does.  That would be
OK, I guess, except that it gets in the way of achieving valuable goals.
Not only does it cost money, but opportunity.

>I seriously think that for all his technology talk, the space program will be
hurt under Clinton.  Especially if, as has happened, in the fact it gets linked
>to defese simply because they both use Aerospace.

I heard recently on the news that this latest STS mission was the last
time the shuttle would be used for military purposes.  That means that
Clinton-Gore would have a hard time cutting it (and, by extension, the
other non-DoD parts of the space program) under the guise of cutting
defense.  But never underestimate the ability of a opportunist demagogue!

On a related note, I assume space will still be a valuable part of the
DoD's strategy, so what will they be using from now on, if not the
shuttle?  Titans and/or Deltas?  Would the DC-1 be a potential market
for the military, or is the market not even a concern, as much as
gettting it to work, at this point?

-Tommy Mac
-----------------------------============================================
Tom McWilliams              | What a tangled web we weave, when at   ". |
[e-mail]      |              ,  .first we .practice .*'  .|
[phone] -or- 353-2986|            '. '  . . to decieve    ,      |
a scrub Astronomy undergrad | After that, the  ,          +             |
at Michigan State University| improvement is tremendous! '.  , .'       |
------------------------------===========================================

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

Date: 9 Dec 92 03:30:37 GMT
From: Ron Baalke <[e-mail]>
Subject: Earth Movie
Newsgroups: alt.sci.planetary,sci.space

In article <[e-mail]>, [e-mail] (Thomas E. Smith [LORAL]) writes...
>>>
>>> When will the Earth movie being made by Galileo be compiled, and when/how
>>> can we see it?
>>

There are two movies that will be made.  The first is called the Earth Zoom
movie, and will cover a 48 period after the flyby as the spacecraft moves
away from the Earth.  The second movie is called the Earth/Moon Conjunction
movie, and the first images for that won't be taken until December 16.
At this time from the spacecraft's perspective, the Moon will appear to
pass very close to Earth, and can be captured in a single field of view
of the SSI camera.  168 images are allocated for this movie and it will
be taken over a 14 hours period.  The movie will show the Moon passing
by as the Earth slowly rotates beneath it.  As far as I know, both movies
will be ready for the December 22 press conference, and most people will
see it for the first time on the evening news the same day.

>I have another question that maybe Ron Baalke can answer. Is Galileo going to
>take any footage of the lunar eclipse tomorrow? I think that would be an awesome
>short movie, and a once in a lifetime chance.
>
No, I don't think so.  Galileo's emphasis on the next couple of days is
on the Earth.

     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | The 3 things that children
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | find the most fascinating:
|_____|/  |_|/       |_____|/                     | space, dinosaurs and ghosts.

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

Date: 9 Dec 92 03:19:48 GMT
From: Ron Baalke <[e-mail]>
Subject: Galileo Cruises By Earth
Newsgroups: sci.space,sci.astro,alt.sci.planetary

Paula Cleggett-Haleim
Headquarters, Washington, D.C.               December 8, 1992
(Phone:  [phone])

James H. Wilson
Jet Propulsion Laboratory, Pasadena Calif.
(Phone:  [phone])

RELEASE:  92-217

GALILEO CRUISES BY THE EARTH

     NASA's Galileo spacecraft flew by the Earth this morning
at 10:09 a.m. EST at an altitude of 189 miles (304
kilometers) above the South Atlantic Ocean, completing a 3-
year gravity-assist program and setting a course to reach
Jupiter in December 1995.

       This, the third gravity-assist for Galileo, added
about 8,300 miles per hour (13,300 kilometers per hour) to
the spacecraft's speed in its solar orbit and changed its
direction slightly so that its elliptical orbit now will
reach to the orbit of Jupiter, about 480 million miles (780
million kilometers) from the sun.

        On its way to the Earth encounter the spacecraft flew
about 68,000 miles (110,000 kilometers) north of the moon at
10:58 p.m. EST last night.  Departing from the Earth in a
slightly southerly direction, it again crosses the moon's
orbit at about 9:15 p.m. EST today.

       The Galileo flight team at NASA's Jet Propulsion
Laboratory, Pasadena, Calif., programmed the spacecraft to
measure the near-Earth environment and observe Earth and the
moon during this flyby.  Scientists will obtain a great many
images and spectral scans of the northern regions of the moon
and of various areas on Earth over a period lasting several
days.  This provides scientific data from new perspectives in
some cases and helps the scientists calibrate their
instruments for the Jupiter orbital mission planned for 1995-
1997.

     The Galileo orbiter will fly ten different elliptical
orbits of Jupiter with close passes by each of the major
satellites and extended observations of the planet and its
magnetosphere.  Galileo's atmospheric probe, which will
descend into Jupiter's atmosphere on Dec. 7, 1995 to observe
that environment for the first time, is being checked out
during the near-Earth flight.

     The Galileo Project is managed for NASA by the Jet
Propulsion Laboratory.  The atmospheric probe is provided by
Hughes Aircraft Company under contract to NASA Ames Research
Center, Mountain View, Calif.
- end -
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | The 3 things that children
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | find the most fascinating:
|_____|/  |_|/       |_____|/                     | space, dinosaurs and ghosts.

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

Date: Tue, 8 Dec 92 16:50:30 -0600
From: [e-mail] (Phil G. Fraering)
Subject: Goldin...

\Scattered throughout the evening were references to national politics.
/Sagan joked about Republican party follies.  Goldin said there was strong

\bi-partison support of the space program.  Even Bush personally asked for
/better public education.  Goldin was not partison, perhaps hoping to keep
\his job in the next administration :-)

As has been said before here, Goldin's a democrat...

Of course, now that the democrats control _everything_... we're all
democrats or out of power... after all, if there are any irregularities
in any of the future elections (which the Democrats will win all of)
a committee of Democrats will be appointed to investigate...

Also, in a stunning display of bipartisanship Gore will prob. push
for having republican Truly put back in as NASA head to assure that
nothing further is done...

;-) hopefully

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

Date: 8 Dec 92 20:37:17 GMT
From: Glenn David Sanders <[e-mail]>
Subject: NASA software standard needed
Newsgroups: sci.space

Does anybody know how to get ahold of the following NASA software
standard:

    70-80-344B (programming standards)

    Please reply by e-mail.  Thanks in advance.

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

Date: Tue, 8 Dec 1992 20:16:56 GMT
From: "Shadan M. Ardalan" <[e-mail]>
Subject: Orbit Question?
Newsgroups: sci.space

In article <[e-mail]> <[e-mail]> writes:
>The trajectories of the russian com-sats are called Molnyia or Tundra
>trajectories. They are highly inclined and do one rev in 12 or 24 hours.
>The apogee where the slowest part of the trajectory is reached is above
>the northern hemisphere in order to provide long coverage. That's why they
>are also high eccentric. Inclination is about 63 deg where the pertubations
>of the argument of perigee are extremly low.
>High inclined geostationary trajectories have a groundtrack like an '8'
>where the node is placed above the equator. They are spending halftime of
>a rev either above each hemisphere.
>Regards
>         -Thorsten-
>

The period of a Molnyia orbit is half a sidereal day (nearly 12 hours).
It's eccentricity is about .72
The information about it's inclination is correct, but it is also important
to mention that the argument of perigee is 270 deg.  This places apogee in
the northern hemisphere, therefore providing most of its coverage there.
What all this buys the Molniya orbit is a repeating groundtrack over the
the area the russians wanted to see the most: simultaneous coverage of
the USSR and the US :-)

Shadan M. Ardalan


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

Date: 8 Dec 92 10:22:12 -0600
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject: Potential uses for the DC-X
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Pat) writes:
>
> So we are spending the money to build the DC-X and flight test it.
> are there any useful science missions it could conduct while up there?

The DC-X has a pretty low altitude, but SDIO has expressed interest in
buying a  suborbital DC-X followon, referred to as "DC-X Prime," for
use as a re-usable sounding rocket.  Sorry, don't have any numbers at
my fingertips;  presumably it's considerably larger than DC-X, but not
as difficult to engineer nor as expensive as DC-Y.

I wonder if the market size is enough to justify DC-X Prime's
development, though.

Bill Higgins                           | Sign in window of
Fermi National Accelerator Laboratory  | Alice's bookstore:
Bitnet:      [e-mail]       | "EVER READ BANNED BOOKS?
Internet:  [e-mail]       |     YOU SHOULD!"
SPAN/Hepnet:      43011::HIGGINS       | Gee, I hope it doesn't become
                                       |   *compulsory*.

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

Date: 8 Dec 92 14:50:45 GMT
From: John C Sager <[e-mail]>
Subject: Rush...
Newsgroups: sci.space

In <[e-mail]>, [e-mail] ("Phil G. Fraering")
writes:

>\Because nobody takes him seriously.  He's just a nut mouthing off.

>Actually I think he was joking...

Guys like that don't have a sense of humour. I expect it was coldly
calculated to further the career of Rush Limbaugh. I'm heartily thankful
that he is an un-person over here, we've got enough self-seekers of our
own:-(

John C Sager                    Mail:    B67 G18, BT Labs
Email:    [e-mail]                Martlesham Heath
Tel:    [phone]                    IPSWICH  IP5 7RE
Fax:    [phone]                    England

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

Date: Tue, 8 Dec 1992 19:25:13 GMT
From: Doug Page <[e-mail]>
Subject: Rush Limbaugh says problems with HST is a DoD hoax!
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Thomas Clarke) writes:
|> In article <[e-mail]> [e-mail] (Doug Page)
|> writes:
|> >
|> > Interesting that you state your opinion that he pays no mind to any opinions
|> > contrary to his own.  It was posted long ago in this newsgroup that he
|> > prefaced this "story" as being ridiculous.  Please note the number of
|> > "open-minded" posters who freely posted what Limbaugh "thinks".  Perhaps
|> > someday they too will stop paying "no mind to any opinions contrary to" their
|> > own.
|>
|> To beat a dead horse (elephant?), I heard him discuss the rumor on the
|> radio.  He did present it as a rumor, but not as a ridiculous rumor.
|> Something to the effect that all the people who use the HST mirror
|> fiasco as an example of America's declining expertise should consider
|> this rumor...  The implication being that while maybe the military
|> is not actually looking for the optical signature associated with
|> the radio emissions of little green men, perhaps the military
|> had some reason to cause the data from the HST to be degraded.  Kind of
|> like the rumors about SEASAT; its synthetic aperture radar detected
|> nuclear submarine wakes all too well -- a definite no-no -- so the
|> military had SEASAT terminated.

I just discussed with several people who heard Limbaugh report this rumor last
week.  None of us heard it the way you report it.  The fact that there is a
rumor is a fact.  He did not report the rumor as fact.  He, in fact, used it
to set up a joke about Carl Sagan.

I was encouraged to check the summary of the show in alt.fan.rush-limbaugh by
the lunch crowd.  I did so, and here's the sumtotal of what Limbaugh said:

   o    Rush normally doesn't deal with rumors, but there's a
    juicy one which he can't resist. This rumor is "floating around
    squid-like" and concerns how the Hubble Telescope was launched
    with one of its camera lenses installed backwards. Of course,
    this event was roundly proclaimed as proof that American industry
    was going to hell in a handbasket.

    The rumor, though, is that the Hubble Telescope is actually
    working flawlessly, and has been ever since its launch. The
    military, though, put out the story about it not working so that
    they could take it over to investigate some mysterious radio
    waves coming from space for the past six years. Now that the
    military's research is done, the Hubble is working flawlessly.

    Rush doesn't give much credence to the rumor, especially since
    Carl Sagan is not involved, and if anyone would be involved with
    alien life forms, it would be Sagan.

Is the rumor ridiculous?  Sure!  Did the rumor say that the HST was being used
to look at the mysterious radio waves?  No.  (An optical telescope can be used
to investigate the SOURCE of radio waves.)  Did Limbaugh say that the rumor
was true?  No.

Whether anyone agrees or disagrees with Limbaugh was not my point.  My point
was that so-called "openminded" individuals were attacking Limbaugh for what
someone said he said.  They made neither attempt to confirm what he said
nor the context of it.  Limbaugh's show is built on satire.  Unfortunately,
many don't seem to be able to recognize satire when it comes from a
conservative position .  Maybe, if Limbaugh hosted SNL . . .

More than enough said,
Doug Page

***  The opinions are mine (maybe), and don't necessarily represent those  ***
***  of my employer.                                                       ***

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

Date: Tue, 8 Dec 1992 16:36:56 GMT
From: Edmund Hack <arabia!hack>
Subject: Shuttle replacement
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Carl Hage) writes:
>Out of curiosity and perhaps a more reasonable comparision, could someone
>post where and how KSC gets it's LOX and LH2?

I know that for Apollo, there was a LO2/LN2/LAr plant adjacent to KSC.
I worked summers for the company and hitched a ride on the company jet
with their top plant engineers down to a launch.  They didn't produce
LH2, but said it was brought in to a holding tank farm near the pads.
The LOX and LN2 was sent in via pipeline. (The LN2 was used to reduce
the risk of fire during fueling as an oxygen displacer and to help quench
the pad after launch.)  I would assume the plant is still there.

This company had a lot of air separation plants and a gas pipeline
system running along the Gulf Coast, but only produced H2 at one site,
and it was gaseous.  LH2 is difficult to deal with and not in high
demand.

--
Edmund Hack - Lockheed Engineering & Sciences Co. - Houston, TX
[e-mail] - I speak only for myself, unless blah, blah..
"You know, I think we're all Bozos on this bus."
"Detail Dress Circuits" "Belt: Above A, Below B" "Close B ClothesMode"

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

Date: 8 Dec 92 20:13:11 GMT
From: Steinn Sigurdsson <[e-mail]>
Subject: space policy
Newsgroups: sci.space,talk.politics.space

Any opinions on what effect having Sally Ride as
science, space and technology co-ordinator will
have on Clinton's space policy???

|  Steinn Sigurdsson    |I saw two shooting stars last night        |
|  Lick Observatory    |I wished on them but they were only satellites    |
| [e-mail] |Is it wrong to wish on space hardware?        |
| "standard disclaimer"    |I wish, I wish, I wish you'd care - B.B. 1983    |

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

Date: 8 Dec 92 21:05:04 GMT
From: "Edward V. Wright" <[e-mail]>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space

In <[e-mail]> [e-mail] (Gary Coffman) writes:

>Mass ratio is a very good measure of margin, and DC-Y's will be very
>very much pushing the envelope.

If that's true, a supertanker must also push the edge of the envelope.
But, of source, that's absurd.


>>Exactly Gary.  Your complaints are the shuttle.  Your solutions are the DC.
>>The shuttle has 4 engine types, separate engines for each mode of flight,
>>three different heat protections, 8 cargo bay doors, .

>Yes, *totally* separate systems, completely different backup systems,
>*exactly* what I'm calling for above.

Those are not totally separate systems, and adding asterisks to every
other word doesn't make them so.  All those systems must operate
perfectly, or near-perfectly, for a Shuttle flight to be a success.


>>DC,x,y,1  will have one common set of engines.  the RCS i think uses
>>LH2/LOX.  The same engines will do orbital manuevers, landing, takeoff.

>Single point failure. One system must do everything.

Just because the DC has multiple engines of one type, that doesn't
make them a single failure point.  By your logic, a four-engine
aircraft like the 747 should have four types of engines -- one
turbojet, one turbofan, one propjet, and one reciprocating engine.
Would it be safer that way?  Of course not.  Just because one engine
fails, that does not mean another, independent engine of the same
type is going to fail also.  Airplanes don't work on the basis of
sympathetic magic.

>Now if *DC-1* can deliver
>10 kilopounds to *orbit* 100 times in a year with no failures, I'd
>be much more impressed. I'd even consider buying a ticket. But there
>are many *giant* steps between DC-X and DC-1.

So lead, follow, or get the hell out of the way.

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

Date: 8 Dec 92 17:33:09 GMT
From: [e-mail]
Subject: US weather satellite question
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (John Roberts)
says:
>
>The US loaned a weather satellite to Europe some years ago (by shifting its
>position to cover Europe), and Europe is returning the favor by loaning one
>of theirs to the US.
>
>John Roberts
>[e-mail]

Just nitpicking here, but.....

I don't think the US actually 'loaned' a satellite to europe. Rather Europe
or more specifically ESA was asked to take over control of GOES-A for the
GARP in 1979.  I quote from the Journal of the British Interplanetary Society
special edition on the European Space Operations Centre (Volume 40 No.6)
and the section by the head of the Spacecraft Operations Division, Mr. D.E.B.
Wilkins on this subject:

"This weather satellite, similar to Meteosat, has been offered by the United
States NOAA (National Oceanic and Atmospheric Agency) to the World Meteoro-
logical Organisation (WMO) as a replacement for the Russian GOMS satellite.
"In 1979 several agencies offered geostationary meteorological satellites for
GARP, the Global Atmospheric Research Project. In the event the Russians could
not provide their GOMS satellite and the USA offered GOES-A for the Indian
Ocean, if ESA could take over control of the satellite. In less than one year,
assisted by NASA and NOAA, ESA had:"
[...list of events during the preparation for taking control deleted....]
" - taken over control of GOES-A at 15degs W longitude, and drifted the sat-
ellite to 57degs E longitude,positioning it and maintaining its station at
this point.  (GOES-A was now designated GOES/Indian Ocean),
" - performed mission control of GOES-I/O from 1 December 1978 to 30 November
1979 when the satellite was drifted eastwards to Guam and returned to NOAA
control.

"This is believed to be an unique example of international cooperation in the
space field." (end quote)

This JBIS was published in June 1987. The above does not appear so unique now
that NOAA will be using Meteosat-P2 in the near future, although spacecraft
control will remain at ESOC.


Standard disclaimer. Nothing to do with my employers.
-peter w-

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Date: Wed, 9 Dec 92 04:01 GMT
From: Karl Dishaw <[e-mail]>
Subject: US Weather Satellites

The discussion on the GEOS-NEXT troubles left out most of America's
weather satellites.  NOAA has four satellites in sun-synchronous (polar
LEO) orbits, 2-3 of them operational, and the Air Force DMSP constellation
has 2.5 operational birds.  Plus there's a Chinese (?) weather satellite
that broadcasts realtime data we can use.

450-mi high closeups don't make for good backdrops on the 6o'clock news
but we are getting a lot of weather data.

Karl
"sold my soul to Uncle Sam . . . now marked down for resale."

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End of Space Digest Volume 15 : Issue 524
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