Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V08/V8_299.TXT

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Subject: SPACE Digest V8 #299

SPACE Digest                                      Volume 8 : Issue 299

Today's Topics:
       Re: Soviet launch 1st Phobos mission & Spacewalk update
              Tethered Satellite System
               Voyager success
                  NASA News
                  NASA News
            Re: Tethered Satellite System
       Re: Soviet launch 1st Phobos mission & Spacewalk update
               Re: Skintight spacesuit
            Re: Electromagnetic Launchers
----------------------------------------------------------------------

Date: 12 Jul 88 08:35:53 GMT
From: xanth![e-mail]  (Kent Paul Dolan)
Subject: Re: Soviet launch 1st Phobos mission & Spacewalk update

In article <[e-mail]> [e-mail] (Paul F. Dietz) writes:
>In article <[e-mail]> [e-mail] (Glenn Chapman) writes:
>>On the
>>other hand it may drive the Russians towards faster implementation of space
>>processing on an industrial scale.  That would return materials both to their
>>economy and provide high tech, high value exports.
>
>I find this utterly unbelievable.  It's clear NASA doesn't have a single
>product that could be made profitably in the space station, and little
>reason to expect any such product exists.  Why should the Soviets, with
>their awful record at developing and marketing high tech products, expect
>success?
>
>It seems incredible to me that, faced with the evidence of what
>bureaucracy did to the US space program, people can still think the
>Soviet space program is some paragon of good planning.  I don't
>see what they're getting that's worth the investment.  And, Glenn's
>exhorations notwithstanding, I don't see why the US should follow
>their lead.
>
>    Paul F. Dietz
>    [e-mail]


The error in this thinking seems to be in the phrase "high tech"; I'd
be quite happy with steel billets and industrial chemical feedstocks.
The greatest existing, easy to see how to exploit, space stuff is the
abundant raw materials within reasonable energy costs of earth orbit.

Kent, the man from xanth.

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

Date: 13 Jul 88 09:50:59 GMT
From: agate!garnet![e-mail]  (Obnoxious Math Grad Student)
Subject: Tethered Satellite System

In article <[e-mail]>, bob@etive (B Gray) writes:
>TSS-1 is manifested for launch on Discovery as STS-46
>on January 17th 1991.

A popular science article on tethered satellites and the US-Italian
project can be found in the 4/87 S&T.

ucbvax!garnet!weemba    Matthew P Wiener/Brahms Gang/Berkeley CA 94720

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

Date: 13 Jul 88 09:45:29 GMT
From: agate!garnet![e-mail]  (Obnoxious Math Grad Student)
Subject: Voyager success

In article <[e-mail]>, karn@thumper (Phil R. Karn) writes:
>Good point. But how many applications really require six second response
>time? Voyager seems to have been highly successful without humans on
>board, despite round trip times measured in hours.

Yes, it has been highly successful.  But not without some extreme diffi-
culties.  [The following is based on the 10/86 S&T account.]

The first major nasty for Voyager 2 was the radio receiver short-circuited
eight months after launch.  The backup proved incapable of changing fre-
quencies.  All this time mission control has had to estimate, within 100
Hz, the effective receiving frequency (the instrument is very sensitive
to temperature).  This is not easy, and a misguess as V2 nears Neptune
could prevent any essential last-minute corrections from taking place.

The second major nasty for V2 was the gearing that controlled the optical
istruments went berserk and then jammed to a halt shortly after reaching
the far side of Saturn.  Numerous photo-opportunies were lost.  The prob-
lem took several years for JPL to diagnose.  It was rather fortunate that
simply heating and cooling got the gears unjammed.  For once, the long time
scales proved a boon.

The third major nasty for V2 was related to the reprogramming of the error
correcting code from a wasteful Golay code to a bit-spartan Reed-Solomon
code.  Six days before U-day the JPL monitor pictures began to go blooey.
Two days were wasted trying to find the problem in JPL software, before
it was generally realized that it was V2.  A bit-by-bit check showed that
a single 0 had flipped to 1, and it couldn't flip back.  A JPL hacker
figured out--overnight--how to program around this.

There were other problems, and only a combination of good luck and ex-
cellent talent has made V2 a success.  I've got my fingers crossed for
Neptune.

ucbvax!garnet!weemba    Matthew P Wiener/Brahms Gang/Berkeley CA 94720

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

Date: 8 Jul 88 00:44:31 GMT
From: nbires!isis!scicom!embudo![e-mail]  (markf)
Subject: NASA News


NASA News - Solid Propulsion Integrity Program Contractor Selected

NASA announced ... that it will negotiate a contract with the Hercules
Aerospace Co., Magna, Utah, to improve the nozzles of solid fueled
rocket motors.

The work is part of the agency's Solid Propulsion Integrity Program.
The objective of the program is to increase the success rate of solid
fueled rocket motors by improving basic engineering in such areas as
material characteristics, design analysis, fabrication and assembly
processes and production evaluation and verification.

The value of the contract is expected to be approximately $12.5 million,
according to NASA's Marshall Space Flight Center, Huntsville, Ala.,
which announced the selection.

The program originated from joint NASA-Department of Defense-industry
studies which identified critical shortfalls in the U.S. engineering
technology base for solid-fueled rocket motors. Proposals for a Solid
Propulsion Integrity Program bondline work package are being evaluated
for award later this summer. This represents NASA's contribution to the
tripartite effort.

NASA engineers managing the program expect to improve confidence in solid
rocket motor launch systems by establishing urgently needed engineering
tools, techniques and data bases specifically applicable to the current
civil and military family of solid-fueled rocket motors.
======================================================================
NASA News Release 88-82 June 21, 1988
By James Cast Headquarters, Washington, D.C.
and Bob Lessels Marshall Space Flight Center, Huntsville, Ala
Reprinted with permission for electronic distribution

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

Date: 8 Jul 88 00:41:57 GMT
From: nbires!isis!scicom!embudo![e-mail]  (markf)
Subject: NASA News


NASA News - Space Station Negotiations with Partners Successfully Completed

Negotiations among the United States, Canada, Europe and Japan on the
framework for the international cooperation in the Space Station program
have been completed.

Completion of talks among the negotiators marks the end of more than 2
years of complex negotiations on the design, development, operation and
utilization of the permanently manned civil Space Station. Spanning
decades, the Space Station will be the largest international scientific and
technological venture ever undertaken.

Cooperation in the Space Station program is the result of President Ronald
Reagan's January 1984 invitation to friends and allies of the United States
to join in the development of the versatile facility and to share in the
benefits of its use. Subsequently, the President has addressed Space Station
cooperation at four intervening economic summits and at numerous bilateral
meetings with the partners' heads of government.

The Congress has also endorsed Space Station cooperation. The NASA
Authorization Act of 1988 directs NASA to "promote international
cooperation in the Space Station program by undertaking the development,
construction, and operation of the Space Station in conjunction with...
the Governments of Europe, Japan and Canada.

The international Space Station complex includes a manned base which will
be operated by an international crew beginning in the mid 1990's. It
also includes elements separate from the manned base. The entire complex
with its diverse capabilities, will be the focal point for free world
space operations into the next century. As an orbiting research laboratory,
the Station will increase scientific knowledge, stimulate the development
of new technology and enable commercial research. Looking to the future,
the Space Station also is required as teh stepping stone for the eventual
expansion of human presence into the solar system, for example, a manned
mission to Mars.

The elements comprising the Station will be provided by the United States
and its partners. The U.S. will provide the overall Space Station framework,
operating subsystems including life support and 75 kilowatts of power,
laboratory and habitat modules and an unmanned free-flying platform
that will be placed in polar orbit for Earth observation.

Canada will provide a Mobile Servicing System which will be used in
conjunction with the assembly, maintenance and servicing of Space
Station elements. Japan will provide the Japanese Experiment Module,
which is a permanently attached pressurized laboratory module, including
an exposed facility and an experiment logistics module. The European
Space Agency will provide a pressurized laboratory module which is
permanently attached to the manned base; an unmanned free-flying polar
platform to work together with the U.S. polar platform; and a man-tended
free flyer to be serviced at the manned base.

NASA has been cooperating since 1985 with its Canadian, European and
Japanese partners in the definition of preliminary design phase of
the project. Such cooperation has resulted in program-level agreement
on the above hardware. The U.S. anticipates spending approximately
$16.0 billion (FY '89 dollars) to develop Space Station hardware.

The total foreign commitment to the Space Station is in excess of $7.0
billion. The European hardware development program will amount to
approximately $4.2 billion; the Japanese, $2.0 billion; and the
Canadian, $1.0 billion. Furthermore, the partners will cover more
than 25 percent of the Space Station's expected annual operating
costs throughout the 20-30 year life of the program.

The document on which negotiations have been completed are a multilateral
intergovernmental agreement (IGA) and three bilateral memoranda of
understanding (MOUs). The IGA contains the broad principles and the
government-level commitments for the cooperative Space Station
program. The three separate MOU's which are between NASA and its
counterparts, provide the technical and programmatic details for the
implementation of the program. Although substantive agreement among
the partners had been reached earlier, today's announcement reflects
the significant stage of achieving agreement among the negotiators on
the actual texts of the IGA and the MOUs.

Negotiations from all four partners have submitted the IGA and MOU
texts to their respective governments for consideration in
accordance with their internal procedures. Signature of the agreements
is expected later this summer.
-----------------------------------------------------------------
NASA News Release 88-74 June 8, 1988
By Mark Hess Headquarters, Washington, D.C.
Reprinted with permission for electronic distribution

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

Date: 13 Jul 88 14:23:55 GMT
From: [e-mail]  (Paul F. Dietz)
Subject: Re: Tethered Satellite System

In article <[e-mail]> [e-mail] (Obnoxious Math Grad Student) writes:
>In article <[e-mail]>, bob@etive (B Gray) writes:
>>TSS-1 is manifested for launch on Discovery as STS-46
>>on January 17th 1991.
>
>A popular science article on tethered satellites and the US-Italian
>project can be found in the 4/87 S&T.

See also Rivista del Nuovo Cimento vol 10, no. 3, 1987 (I hope I spelled
that right).  This issue is a survey of the TSS project and the physics
involved, including the use of tethers for propulsion and energy generation.

    Paul F. Dietz
    [e-mail]

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

Date: 13 Jul 88 14:13:39 GMT
From: [e-mail]  (Paul F. Dietz)
Subject: Re: Soviet launch 1st Phobos mission & Spacewalk update

In article <[e-mail]> [e-mail] (Kent Paul Dolan) writes:
>
>The error in this thinking seems to be in the phrase "high tech"; I'd
>be quite happy with steel billets and industrial chemical feedstocks.
>The greatest existing, easy to see how to exploit, space stuff is the
>abundant raw materials within reasonable energy costs of earth orbit.

Glenn was refering, I believe, to microgravity manufacturing in LEO.
No ET sources of materials involved.  Given the rate at which the
Soviet program is moving, I don't think exploitation of ET resources is
around the corner.

The country I'd worry about most in space is Japan.  They'll have
their own heavy booster in six years or so.  They will no doubt target
the most lucrative space market: information handling satellites.
Which we will have frittered away due to inane export restrictions,
concentration on microgravity PR stunts, and the continuing dependence
on inadequate launchers.

    Paul F. Dietz
    [e-mail]

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

Date: Wed, 13 Jul 1988 13:49-EDT
From: [e-mail]
Subject: Re: Skintight spacesuit

If the suit is holed or ripped, the result is not going to be fatal as
it would be in a hard suit. You will not lose breathing air unless you
smash your face plate or damage your tanks. Nasty 'burns' on exposed
areas seem much more preferable to me than turning purple.

I don't think I micro strike is necessarily fatal either. The smaller
particles vaporized on contact and would probably only cause nasty
surface wounds. Larger particles would be like being getting shot by a
gun: possibly fatal, but even Reagan survived getting hit. Lets compare
the results with a hard suit. In most cases a simple adhesive patch
should cover the damage until the victim can get back inside. The patch
probably needs to be placed within minutes, and probably will hold for
many minutes, if not hours or days if such were necessary.

    1) The escaping gases fling you into a random tumble while you
       have seconds to do something.

    2) You loose skin pressure AND breathing air simultaneously.

    3) The decompression may be explosive rather than
       rapid. Explosive decompression can cause internal organs
       to self destruct.

    4) Assuming survival of the first instants, you will have only
       seconds to patch it while spinning wildly.

    5) It may be difficult to apply an external patch capable of
       of holding 15 PSI presssure (a hard suit). I suspect even
       the shuttle suit (4 PSI O2?) might be difficult to patch
       effectively under emergency conditions.

    6) The survivor will probably have sustained considerable
       physical damage not directly related to the actual cause
       of suit failure.

Skintights have other safety advantages.  They could be worn at all
times on space vehicles/stations. An onboard depress accident due to
micrometeor strike or system fault would be far less likely to be fatal
if all you had to do is grab a helmet and seal it down. Even children
could be trained to respond to such an alert. This is a necessary
safety consideration because I hope we have intentions of raising
families off planet. Otherwise what is the purpose of it all?

Since the suits 'breathe' they should be reasonably comfortable in a
controlled environment.  Additionally, they could be designed in very
colorful and personal patterns such that even in vacuum individuals
could identify each other by their personallized color patterns.

:-) I suspect wearing such suits all the time will lead to a strong
desire to keep in good shape. Everyone will show see exactly what shape
your tummy is in. But then, I there is no reason why 'normal' earthworm
garments could not be worn over top of the suit. Imagine running into a
longhaired techy servicing your external electronics dressed in
bluejeans and t-shirt...

One thing can be said for the hard suit. They are a double use
technology: space suit and coffin.

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

Date: 13 Jul 88 05:33:41 GMT
From: pyramid!pyrnj!dasys1![e-mail]  (Tom Neff)
Subject: Re: Electromagnetic Launchers

In article <[e-mail]> [e-mail] (Paul F. Dietz) writes:
>I was thinking some more about the perennial problem of cheaply lifting
>mass into orbit; specifically, using electromagnetic launchers.  ...

>The vehicles could not just be unguided projectiles, like bags of
>lunar material launched using a mass driver, since vehicles are
>placed onto elliptical orbits with perigee beneath the Earth's surface.
>Onboard rockets must lift the perigee above the atmosphere and guide
>the vehicle to a space station.

No, you are forgetting the concept of the "catcher."  I see you have
been thinking hard about this subject, but not reading up on the prior
literature.  I'm sorry I don't have references at hand (I'm at a
friend's place for a bit), but basically you put a catchment net of
some kind into a parking orbit, and target the launched mass at the
net.  Each capture adds momentum to the orbiting net assembly of
course, which must be compensated for eventually; but not right away.
(You can rail launch reaction mass for a subsequent retrofire after
every N captures, for instance.)


--
Tom Neff            UUCP: ...!cmcl2!phri!dasys1!tneff
    "None of your toys    CIS: 76556,2536           MCI: TNEFF
     will function..."    GEnie: TOMNEFF           BIX: t.neff (no kidding)

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

End of SPACE Digest V8 #299
*******************