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Date: Tue,  3 Oct 89 01:49:27 -0400 (EDT)
Subject: SPACE Digest V10 #101

SPACE Digest                                     Volume 10 : Issue 101

Today's Topics:
          Soviet activities with MIR for 1989-1990.
         Re: What's Wrong With HR2674. (long)
     Call for discussion for the creation of "rec.models.rocket"
          Re: Risk of NOT launching Galileo
      Re: Alternative Space Goals, Anyone? (was Re: SpaceCause)
         Re: ...hospital radiation machine...
          NIMF proposal from Martin Marietta
----------------------------------------------------------------------

Date: 26 Sep 89 16:10:22 GMT
From: wrksys.dec.com![e-mail]  (CUP/ASG, MLO5-2/G1 6A, 223-3283 26-Sep-1989 1139)
Subject: Soviet activities with MIR for 1989-1990.


        The following is the 1989-1990 timetable for the expansion of the
    Mir space station based on a recent Aviation Week & Space Technology
    interview with Soviet space program managers:

  September     Changeout of Mir's computer memory with new unit brought
        up by Progress M-1.

  October 16    Launch of Module D (aka Service Module).

  Between October 16 and October 23

        Progress M-1 undocks from Mir's forward docking port and
        will be sent into a destructive reentry (the Progress M
        spacecraft does have the ability to fly with a recoverable
        reentry module similar to the one used on the Soyuz but
        Progress M-1 and probably M-2 will not have such a module).

  October 23    Module D will dock with Mir at the forward axial port and
        will shortly thereafter transfer to one of the axial ports
        automatically using its manipulator arm.

  October 25    Soyuz TM-8 will be moved from the rear docking port to
        Mir's forward facing axial port.

  October 27    Progress M-2 will be launched.

  October 29    Progress M-2 will dock at Mir's rear docking port and
                unloading will begin.

  January 28    Soyuz TM-8 will be moved from the forward axial docking
        port to the rear docking port which will be left vacant
        after Progress M-2 leaves.

  January 30    Launch of Module T (aka Technology Module).

  February 6    Module T will dock at Mir's forward facing axial docking
        port and will then be moved to the radial port opposite
        Module M.

  February 11    Soyuz TM-9 with cosmonauts Col. Anatoly Solovyov and
        A. Balandin will be launched to Mir.

  February 13    Soyuz TM-9 docks at Mir's forward axial port.

  February 19    The Soyuz TM-8 crew of Viktorenko and Serebrov will leave
        Mir for home.

  February 21    Soyuz TM-8 lands on Earth.

        The present EVA schedule for the Soyuz TM-8 crew follows:

  Between September and December:

        The crew will perform three EVAs:

        > #1 Shift the female docking device to another of Mir's
             forward docking ports.
        > #2 Remove the French Echantillons experiment.
        > #3 Install two star trackers on the Kvant module.

  December    The crew will perform two EVAs using the new MMU with the
        MMU at the end of a 60 meter long tether:

        > #4 Basic checkout of MMU lasting 5 hours.
        > #5 Evaluate MMU's ability to perform work outside.

        The next module to be launched to Mir will be Module O (aka
    Optical Module).  Module T will have its solar panels removed and
    mounted on Kvant and then it will be moved to another radial port.
    Module O will then occupy that port.  The last module will be a
    ecological platform with an international payload and will be placed
    opposite Module T.  No launch date for the next pair of modules has
    been announced.

        Larry Klaes  [e-mail]
             or - ...!decwrl!wrksys.dec.com!klaes
                 or - [e-mail]
                     or - [e-mail]

        EJASA Editor, Astronomical Society of the Atlantic

             N = R*fgfpneflfifaL

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

Date: 26 Sep 89 17:20:13 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: What's Wrong With HR2674. (long)

In article <[e-mail]> [e-mail] (Jim Bowery) writes:
>> Despite Kieran's modest lingering connection with U of T, he is employed
>> full-time by a small, struggling Canadian aerospace company these days.
>That explains why he is so upset about the trade-restriction section of
>HR2674 that he wants to reduce its chances for passage...

My, we are just full of nasty suspicions about ulterior motives, aren't we?
The company Kieran works for is on the payload end, not the launcher end,
so he's not affected by the trade-restriction stuff.

>> Did you notice that HR2674's distant ancestor, the Commercial Space
>> Incentives Act, had a clause in it specifically limiting OCST authority
>> to safety considerations?  There was a reason for that.)
>Yes, and the reason for it isn't sufficient.  While regulatory powers can,
>are and will be abused, it isn't reasonable to simply eliminate regulation.

The call is not for elimination of regulation, but for restricting it to
its proper function:  safety.  Not to suppressing any payload or launcher
that the current Administration doesn't approve of, which OCST is perfectly
legally capable of doing now.

>The first time one of Jerry Pournelle's buddies builds a bomb thinly disguised
>as a rocket and insists that the government blow it up on a government owned
>launch pad, you can bet any anti-regulatory clauses in any legislation would
>be removed...

This is a total non sequitur; can you explain how you got from what I said
to this?  For one thing, safety is precisely the area where regulation was
to *remain* in effect.  For another, unless I'm grossly misremembering it,
nothing in the proposal said that the government had to provide launch
facilities to anybody ever.  Did you ever *read* the Commercial Space
Incentive Act?

Quite aside from all that, I think it is high time we started blowing up
a few experimental rockets again.  Progress requires setbacks; if you
insist on everything being successful, the result is stagnation.  Which
is precisely what we see in NASA and the traditional launcher companies:
all the technology is 20-30 years old and very little effort is being
made to improve on it.

>> Don't kid yourself; the *really*
>> private launch industry in the US is very young and small and fragile, and
>> the government could easily step on it "in the national interest".
>I agree, and therefore it is critical that HR2674 be passed as soon as
>possible.

HR2674 seems likely to benefit, primarily, General Dynamics, Martin Marietta,
and McDonnell Douglas.  None of whom bear any resemblance to the people I
was talking about.  I support HR2674, as an eminently sensible first step,
but it's not going to do much to support the new companies -- which is where
the real hope of US spaceflight lies.
--
"Where is D.D. Harriman now,   |     Henry Spencer at U of Toronto Zoology
when we really *need* him?"    | uunet!attcan!utzoo!henry [e-mail]

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

Date: 26 Sep 89 14:54:31 GMT
From: [e-mail]  (R. M. Jungclas)
Subject: Call for discussion for the creation of "rec.models.rocket"



        CALL FOR DISCUSSION

For the creation of rec.models.rocket (unmoderated).

It is proposed that a newsgroup "rec.models.rocket" be created
for the discussion of any aspect relating to model rockets OR
high power rockets. The purpose of the this newsgroup would be
for exchange of information to anyone wanting TO BUILD, FLY OR
USE model rockets or high power rockets.

The term "model rocket" is defined based on non-metallic
structural components, weight, propellant and total impulse
restrictions, electrical ignition, recovery devices and
FACTORY-MADE, solid propellant engines. The term "High Power
rocket" refers to any rocket using model rocket technology
(as described above) except without the weight, propellant
and total impulse restrictions of model rocketry.  High power
rockets have been arround for 10 years, but only popular
within the past few years.  Both of these forms of rocketry
use a "Safety Code" which permits their LEGAL use in all of
the states. Model rocketry is also available in Canada, Great
Britain, the Soviet Union and other countries.

The term "amateur rocketry" refers to all other non-professional
rocket activities.  Included in the last class, are "basement
bombers," any attempts to make homemade engines, and anything using
metallic structural parts.

Model rockets have been arround for 31 years. Many of you may be
aware of Estes and MRC model rockets currently available in most
hobby and toy stores or of manufacturers that are now out of business:
Centuri, Cox, MPC, etc.. Manufacturers of High Power kits/engines
include Lots of Crafts/Precision, North Coast Rocketry, U.S. Rockets,
AeroTech and Vulcan.

As you may be aware the first commercial launch vehicle launched
from Cape Canveral was the LOFT-1. (see Jan or Feb. issue of Science)
This was a "high power rocket" as defined above. In addition, off-the-shelf
video recorders and custom built video cameras/transmitters have been
sucessfully flown. One such flight resulted in a video transmission
that was broadcast on live television.

Your comments and/or suggestions relating to this newsgroup
are welcome. The call for discussion will end on October 14th
unless issues and concerns need to be resolved.

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

Date: 27 Sep 89 16:15:10 GMT
From: frooz![e-mail]  (Steve Willner)
Subject: Re: Risk of NOT launching Galileo

From article <[e-mail]>, by [e-mail] (Tom Neff):
> It's a nice point that scratching Galileo could cost us weather
> knowledge, but Mission To Earth will do it better.

Are you sure?  Presumably the same basic physics govern the weather
systems on the two planets, but the conditions are utterly different.
The way to verify models - which is all we have - is to test them on
systems that are as different as possible.  Thus I expect that we will
learn things by studying Jupiter's weather that we would never learn by
studying only Earth's.  Certainly there is considerable _risk_ that this
is true.

Of course I agree that we need to do Mission to Earth as well.
-------------------------------------------------------------------------
Steve Willner            Phone [phone]         Bitnet:   willner@cfa
60 Garden St.            FTS:      830-7123           UUCP:   willner@cfa
Cambridge, MA 02138 USA                 Internet: [e-mail]

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

Date: Wed, 27 Sep 89 11:18:24 PDT
From: Peter Scott <[e-mail]>
Subject: Re: Alternative Space Goals, Anyone? (was Re: SpaceCause)

bfmny0![e-mail]  (Tom Neff) writes:

>In article <[e-mail]> [e-mail] (Brian Yamauchi) writes:
>>Still, your multinational corporation, entrepreneurial startup, or
>>non-profit organization still needs to *some* plan of action.  I'm
>>talking about goals as plans, not (necessarily) policy.
>
>Yes, but that should be up to them, not us.  People with no profit
>motive, sitting around and theorizing what *should* be done in space, is
>what got us in the mess we're in today.

Oh... you mean like what we do on the net...?

Peter Scott ([e-mail])

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

Date: 27 Sep 89 17:03:21 GMT
From: [e-mail]  (Jon Jacky)
Subject: Re: ...hospital radiation machine...

This incident is written up in the booklet, THE RADIOLOGICAL ACCIDENT IN
GOIANIA, Interanational Atomic Energy Agency (IAEA), Vienna 1988.  In the
University of Washington (Seattle) Engineering Library it has call number
TK/9152/R36/1988.  If your library doesn't have it, you can probably get it
from us via interlibrary loan.  (Goiania is the town in Brazil where this
occured).

Briefly, here's what happened: A private radiation therapy clinic moved,
taking along its cobalt 60 machine but leaving behind a Cesium-137 machine
in a totally unsecured building.  Some people entered the building and took
the Cesium unit for scrap, not knowing what it was.  The salvagers opened
the source capsule; Cesium 137 was present as the cesium chloride salt, which
is highly soluble and readily dispersable.  People were fascinated by the
glowing substance, carried it around in their pockets, got it on their hands
and faces before eating, etc.  After a few days several of them got sick.
One of the people made the connection with the source and took the fragments
to the public health officials.

Eventually, four people died.  28 people suffered radiation burns.  14 people
were hospitalized and decontaminated.  112,000 (!) people were examined.
Residences and public places were contaminated.  Seven residences and several
other buildings had to be demolished.  About 3500 cubic meters of dirt and
rubble were hauled away to a radioactive waste dump site.  (The cover of the
report has a photo of a guy in a moon suit next to a bulldozer).

The IAEA report also reviews similar incidents that happened in Mexico City
(1962), Algeria (1978), Morocco (1983) and Ciudad Juarez in Mexico (1983).
You may have read about this latter incident, in which Cobalt from a salvaged
machine found its way into steel table legs that were imported into the USA.

What's this doing in sci.space anyway?

Jon Jacky
Department of Radiation Oncology RC-08
University of Washington
Seattle, Washington 98195

[e-mail]
...!uw-beaver!uw-june!jon

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

Date: 27 Sep 89 04:55:09 GMT
From: att!chinet![e-mail]  (Doug Price)
Subject: NIMF proposal from Martin Marietta

I have a copy of "The NIMF - Nuclear Rocket Using Indigenous Martian Fuel,"
by Robert M. Zubrin of Martin Marietta.  As has been noted earlier, this
is a fascinating paper on the use of NERVA-style nuclear rockets for
missions to Mars and beyond.  The most striking thing about this paper is
that it completely turns the economics of interplanetary travel upside down.

Of course, the word "nuclear" strikes terror into the hearts of all those
neo-Luddites out there, so let's deal with the negatives before the positive
components, and take a look at some of the salient comments in the paper:

    "... set against all these advantages (sic) for the NIMF
     is the fact that the NIMF carries a nuclear reactor.  However
     the NIMF reactor carries a radioactive inventory about 6
     orders of magnitude less than a power reactor, which will
     not only be a relief to the Martian Environmental Protection
     Agency, but eliminates the central engineering headache of
     nuclear reactors, to wit the possibility of meltdown caused by
     radioactive decay heat if cooling is lost.  This small
     radioactive inventory represents a small hazard compared to
     that presented by the chemical alternative to the NIMF
     (a chemically powered lander, - DHP) which will be virtually
     a flying bomb, a lightly built structure filled to the gills
     with toxic gas and chemical high explosive."

I talked to Zubrin at the Space Development Conference about the level of
radioactivly that could be expected in the NIMF reactor at its return to earth
orbit, and he said basically that the reactor operates for such a short
period over its entire life that its total residual radioactivity amounts
to the tens of curies.  The worst case scenario of an uncontrolled burn-up
in earth's atmosphere after one or more Martian missions would be trivial
(though, of course, there are plenty of people out there that would find
this concept horrific as well.)

So, now that the "nuclear" debate has hopefully evaporated in a puff of
logic, lets get on to the good stuff; what can this technology do for us?

First, the basic parameters of the NIMF.  Here is a table of ideal specific
impulses for the variously available Martian propellants:

    Temperature   CO2    H2O     Methane     CO or N2    Argon

      2800K       283    370       606          253       165
      3000K       310    393       625          264       172
      3200K       337    418       644          274       178
      3500K       381    458       671          289       187

2800K temperature output was demonstrated with NERVA.  3000K appears to
be attainable with appropriate modernization of the NERVA technology.
3200K is possible with the use of modern ceramic fuel elements.  3500K
can be considered the theoretical upper limit with a solid core nuclear
rocket.

CO2 is the easiest propellant to use, as it constitutes 95% of the Martian
atmosphere.  The specific impulse is on the same order as Oxy/Hydrogen chemical
rockets, BUT, the point is that this reaction mass is easily available at
the destination, rather that having to drag it all the way from earth.  The
electrical cost of liquifying the CO2 from the atmosphere is 84 kilowatt/hours
per metric ton.  The thermal output of the reactor would be on the order of
1000 Megawatts, so putting a relatively modest electical generation capability
aboard the spacecraft would permit the NIMF to reload its reaction mass in
extremely short order (Zubrin sights a figure of 14 hours for a 40 metric
ton spacecraft with 1 Megawatt of electrical generating capacity.)

Using indigenous propellants, the NIMF can hop all over the planet, as many
times as it wants, while a chemically powered lander would only be able to
land in one place, and be electically impoverished as well.  Just think
of what a rover vehicle could do if it had virtually unlimited electrical
power from the lander.

And here is one of the most interesting points.  If water is used as the
reaction mass, the NIMF can launch from Mars directly back into an earth
return trajectory!  While we could not depend on the availability of water
on the first missions, later ones might be able to take advantage of this
increase in specific impulse.

NERVA style rockets used as interplanetary tugs could achieve specific
impulses of 950 with hydrogen as the propellant.

There are lots of other details in the paper related to the relative
tradeoffs of specific mission profiles, propellant provisioning, spacecraft
configurations, and possible multiple visits and sample returns from the
outer planets (and a profile for a sample return from the surface of Venus!)
Anyway, recommend that you send to Zubrin himself to get a full copy of
the paper.  Unfortunately, I believe the politics of the "N" word may
easily put the kabosh on the whole thing.

--
                        Douglas H. Price
                        [e-mail]
                        [e-mail]

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

End of SPACE Digest V10 #101
*******************