Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V10_0/V10_081.TXT

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Subject: SPACE Digest V10 #81

SPACE Digest                                      Volume 10 : Issue 81

Today's Topics:
             Re: Mars Mission ship design
            Re: Re: Saturn V & F-1
           Re: NASA forced to photo Cydonia
       Galileo Jovian atmospheric probe -- is it sterilized???
           Plutonium-power for space craft .. how ?
National student winners named in space science competition (Forwarded)
     Re: Galileo Jovian atmospheric probe -- is it sterilized???
        Re: More details about the Soyuz TM-8 docking
              Ulysses at Jupiter
        Re: Printing On a LaserWriter -- hints
----------------------------------------------------------------------

Date: 16 Sep 89 05:16:39 GMT
From: ogccse!blake![e-mail]  (William Lewis)
Subject: Re: Mars Mission ship design

In article <[e-mail]> [e-mail] (Kevin Bagley) writes:
>In article <[e-mail]> [e-mail] (Jesse M. Mundis) writes:
>>Just some general details/suggestions for design:
>
> 1)     Design the upcomming space station to withstand a specific
>        amount of thrust. If the soviets can live in MIR for a
>        year, surely some hardy US astronauts could manage a couple
>        of years in something as plush as Freedom.
>
> 2)     If it's decided there has to be gravity, use two modules
>        connected with an access tunnel. Start it spinning.
>        Cheaper and easier to build than a ring. Also, I don't
>        think we need enough space to warrant a ring.
>         __________                             __________
>        |  Gravity |       Access_Tunnel       |  Gravity |
>        |  Module  =============(_)=============  Module  |
>        |__________|    Connects to Freedom    |__________|

  As someone else already remarked before I could reach the F key
([e-mail]), this could cause problems thrusting and
stuff, so using cables and a winch is probably better. And I'd think
easier, safer (less puncture/crack surface area), lighter, etc. What about
changing step 1 to read ".. to withstand a specific amount of thrust
[along one axis only necessary], as well as putting a big hook at
one end." Then the diagram would look like this:

       _____                              ____________
      (_____)           (string)          | Fuel for |
   *============\_)---------------------(*)  return  |
      (_____)                     (winch)^|  trip    |
                 (hook)                   |__________|
   Space Station                               |
     Freedom                              =*>--'  (engine on boom)




  Actually I guess the winch isn't necessary, although it may be useful
to vary the speed of rotation of the whole thing (by reeling the
fuel tanks & station in and out). My freshman physics fails me when I try
to remember whether reeling things in and out (without changing the
rotational inertia) will change the pseudo-gravity. In any case, reeling
it WAAAAY out might be useful for small course corrections; the engine
can fire on an arc, without having to de-spin the assembly and re-spin
it (which would take fuel!).
  The problem is, the "craft" needs to be able to:
   1. Stop itself when it gets to Mars (difficult with no gravity
       assisit available?) as well as stopping the fuel tanks for 2 and 3.
   2. Bump itself outof Mars orbit and back into transfer orbit (them
       ellipses's got a name -- Hohmann?) as well as bumping the fuel
       for step 3. This is easier than #2, but only because you don't
       have to accelerate as much fuel. Same delta-v though...
   3. Stop once you're at earth. Use the moon for gravity assist.

  Note I left out step 0, accelerating all 3 fuel tanks and the station,
but presumably we can put all sorts of crud in orbit for that. I wouldn't
want to rely on a catcher for the return trip -- what if the launch gets
delayed? =8(

> 3)     Attatch boosters, BIG fuel tanks, landing, and exploration
                           ^^^^^^^^^^^^^^
 ouch, yep.

> 2)     Anybody know the estimated mass of Freedom. Using Lunar gravity
>        assist, how much fuel/thrust would be needed. Don't forget the
>        return home requirements.

   probably something along the lines of "REALLY, REALLY HEAVY. YOU
EXPECT TO MOVE THAT THING? YOU'RE CRAZY". =8( .  Oh well, it was a good idea.

>
> 3)     How long would the trip take? How long would it take to build
>        this contraption?
>
> 4)     How many people should go? How long should they stay?
>


   I seem to remember in some story (probably Heinlein's The Rolling Stones)
that the correct alignment of Earth and Mars occurs every 26 months (or
something close). This is an alignment such that going into a transfer
orbit at Earth will actually arrive at Mars, instead of "arriving
foolishly at some totally untenanted part of Mars' orbit" (one of my
favorite quotes from tRS..). Presumably it's once-every-26 months
going the other way, too, although (fortunately) not the same orbit
(otherwise you'd have to leave as soon as you got there...) Unfortunately
I don't have any hard numbers handy, so I can't calculate much... However,
the length-of-stay is contant: there are `windows' for leaving Mars, too.
Presumably we'd want to leave as soon as possible! Looking at the shape
of the orbit I'd **guess** that the trip time would be 7 or 8 months,
each way. It's some function of Terran and Martian year lengths, greater
than Earth's half-year but less than Mars'.  A wild guess gives a couple
months' time in Mars orbit for the trip. If/when I find real numbers I'll
work it out and post the results (assuming (a) people are still interested,
and (b) no-one else does it before me).


       --- phelliax
           "I'm not a professional calculator of transfer orbits, but
            I play one on Usenet."

--
[e-mail]        [phone]      Seattle, Washington

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

Date: 17 Sep 89 07:01:45 GMT
From: bfmny0![e-mail]  (Tom Neff)
Subject: Re: Re: Saturn V & F-1

In article <[e-mail]> [e-mail] (Greg Lindahl) writes:
>Of course, the main competition to the S5 would be the shuttle-C. The main
>engines for the shuttle-C are flying today. By your own argument, it must
>be cheaper to build shuttle-C using existing components than to reconstruct
>the Saturn V from rusting originals.

It might indeed be cheaper to do this if an industrial consortium hired
the engineers and said, "do it."  If we wait for NASA to do it, however,
it will cost much more.

A good rule of thumb is: whatever NASA finally does ends up costing more
than anything else they might have done.
--
'We have luck only with women --    \\\     Tom Neff
          not spacecraft!'         *-((O    [e-mail]
 -- R. Kremnev, builder of FOBOS      \\\   uunet!bfmny0!tneff (UUCP)

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

Date: 16 Sep 89 12:13:24 GMT
From: b.gp.cs.cmu.edu![e-mail]
Subject: Re: NASA forced to photo Cydonia

In article <[e-mail]>, [e-mail] (Ken Schmahl) wrote:
 >building things from those of humans.  What he's looking for are unusual
 >geometric patterns that indicate the presence of intelligence.  "I

The question, of course, is on which side of the camera the intelligence
is located....
--
UUCP: {ucbvax,harvard}!cs.cmu.edu!ralf -=-=-=-=- Voice: [phone] (school)
ARPA: [e-mail]  BIT: ralf%cs.cmu.edu@CMUCCVMA  FIDO: Ralf Brown 1:129/46
FAX: available on request                      Disclaimer? I claimed something?
John Gilbert on a Chordal Graph handout:
   "Lemma 3 very pretty, with conditions very few, but the proof of the poor
    lemma is impossible to do."  (quoted in Upson's Familiar Quotations)

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

Date: 18 Sep 89 16:38:47 GMT
From: hubcap![e-mail]  (Steve L Vissage II)
Subject: Galileo Jovian atmospheric probe -- is it sterilized???

If some Earth bugs actually do have the tenacity to travel sevaral hundreds
of millions of miles to Jupiter, is it not likely that most life on Jupiter
will have the tenacity to survive it?

Steve L Vissage II
[e-mail]

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

Date: 18 Sep 89 15:03:41 GMT
From: jarvis.csri.toronto.edu!utgpu!utzoo!yunexus![e-mail]  (Tony Wallis)
Subject: Plutonium-power for space craft .. how ?


(Sorry if this has been covered in sci.space or sci.space.shuttle.
 I do read sci.physics and sci.energy regularly.)

There are media reports of attempts to legally halt the launch of
Galileo on the grounds that it contains many kilos of Pu in its
power source, and should there be a launch accident there would be
lots of plute all over the place etc. etc.

Other reports emphasize that there is NOT a nuclear REACTOR on board
Galileo.

So .. *physics* question : how do you use many kilos of Pu to provide
power at space craft levels without using a self-sustaining fission
chain-reaction ?

Follow-ups to sci.physics

--
Tony Wallis   [e-mail]    (York U.  Toronto  Canada)

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

Date: 18 Sep 89 21:30:54 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: National student winners named in space science competition (Forwarded)

Terri Sindelar
Headquarters, Washington, D.C.                 September 18, 1989


RELEASE:  89-146

NATIONAL STUDENT WINNERS NAMED IN SPACE SCIENCE COMPETITION


     NASA and the National Science Teachers Association held the
9th annual Space Science Student Involvement Program (SSIP)
competition in Washington, D.C., the week of Sept. 14-16.
National SSIP winners were selected in three competition
categories:  Space Station Freedom experiment proposal, school
newspaper promotion, and Destination Mars team competition.

     In the Space Station Freedom experiment proposal
competition, eight national winners presented proposals to the
selection panel on Sept. 14.  Selected from over 1,600 proposals,
the following are the three national scholarship recipients,
their proposals and awards:

     First Place:  Diane M. Fogel, Landsdale, Pa.  Topic:  "The
Effects of Calcitonin in Establishing Calcium Homeostasis in
Microgravity."  The proposal examines the effects of the hormone
calcitonin and Vitamin D in reducing bone loss in microgravity.
Fogel was awarded a $3,000 scholarship and a Tandy computer.

     Second Place:  Bianca Santomasso, New York City.  Topic:
"Determing the Effect of Microgravity on Circulation to the Hands
and Feet in Humans through the Measurement of Nail Growth."  Her
proposal states that because circulation to the hands and feet
has been shown to have an effect on nail growth, measuring this
growth in microgravity would help determine whether
weightlessness has some effect on circulation to these areas.
She was awarded a $2,000 scholarship and a Tandy computer.

     Third Place:  Mark G. Baxter, Durham, N.C.  Topic:  "Effect
of Microgravity on the Membrane Transport System of Chorella."
This research, on the ion absorption rate in the active transport
system of algae, could shed light on the ability to grow
hydroponic plants in space as a potential food source and as a
water purification system.  Baxter won a $1,000 scholarship and a
Tandy computer.

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

Date: 18 Sep 89 12:38:27 GMT
From: cs.utexas.edu!uwm.edu!mailrus!sharkey!itivax!vax3![e-mail]  (Allen W. Sherzer)
Subject: Re: Galileo Jovian atmospheric probe -- is it sterilized???

I while back somebody posted details of an Air Force launch from
Vandenberg where the rocket exploded and dumped an RTG into the
Pacific. The story went on to say that the Air Force found the RTG,
cleaned it up, and used it for another satellite. Can anybody post
the details (names & dates)? We need the information for a letter
to the editor.

  Allen

----------------------------------------------------------------------------
|  Allen Sherzer                     | DETROIT:                            |
|  [e-mail]                       | Where the weak are killed and eaten |
----------------------------------------------------------------------------

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

Date: 18 Sep 89 21:01:28 GMT
From: crdgw1!crdos1![e-mail]  (Wm E Davidsen Jr)
Subject: Re: More details about the Soyuz TM-8 docking

[e-mail] (Glenn Chapman) writes:
|
|       Some more information was given on the shortwave about the USSR's
|  Soyuz TM-8 mission.  About 48 hours after launch the Soyuz approached the
|  Mir station slowly at its Kvant (rear) end.  A few meters from the docking
|  port the autodock system failed.  The crew of Alexander Viktorenko and
|  Alexander Serebrov then pulled the capsule away from the station.  After
|  a conference with the ground controllers it was decided to go ahead and
|  try a manual docking rather than another automatic attempt.  This was quickly
|  accomplished.

  This brings back a faint memory which someone can probably clarify. At
one point in time the US and USSR had a docking in space, and my
recollection is that the final manuver was done by the US because the
USSR did not have a reliable computer assist on their vehicles.

  More recently I thought that the USSR was able to do unmanned
dockings. I am obviously not remembering all of the details, could
someone fill in on either or both of these examples of the status of
automatic docking? Was the unmanned docking actually human controlled by
a remote? The time lag is short enough that I suspect it could be done
that way.
--
bill davidsen    ([e-mail] -or- uunet!crdgw1!crdos1!davidsen)
"The world is filled with fools. They blindly follow their so-called
'reason' in the face of the church and common sense. Any fool can see
that the world is flat!" - anon

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

Date: 19 Sep 89 00:44:51 GMT
From: mcsun!ukc!icdoc!cam-cl![e-mail]  (Kish Shen on jenny)
Subject: Ulysses at Jupiter

I got one reply by e-mail to my question about Ulysses and its encounter
with Jupiter:

--------
#
#I cannot post to the system so perhaps you could forward this.
#
#Ulysses carrries nine instruments.
#
#Magnetometers to measure magnetic fields in space.
#
#Solar-wind plasma experiment to study protons, electrons in the solar wind.
#
#Solar-wind ion-composition spectrometer
#
#Energetic-particle composition experiment
#
#Low-energy charged-particle detector
#
#Cosmic-ray and solar-particle instrument
#
#Unified radio and plasma-wave experiment
#
#Solar flare x-ray and cosmic gamma-ray burst experiment
#
#Cosmic dust experiment
#
#Coronal sounding
#
#Gravity wave search
#
#Ulysses is designed to study solar physics and I believe the flyby of
#Jupiter is too fast to do anything meaningful there.
#
#Also, Galileo will get to Jupiter in 1995 and stay there for 5 years.
#
#Hema Murty , Institute for Aerospace Studies, University of Toronto,
#4925 Dufferin St., Downsview, Ontario M3H 5T6

------

Would Ulysses be flying past Jupiter much faster than the Voyagers and the
Pioneers? Also, can't some or even most of the instruments return useful
data at Jupiter as well, even though they were designed for solar physics?
Since the flyby of Jupiter is for "free", surely some useful data can be
returned.

I assume that any data collected could be used to compliment data gathered
by Galileo, which would of course return much better data of Jupiter. However,
would it not be a bonus to be able to gather data from different points in
the Jupiter system at the same time?

Kish Shen
Computer Lab.
University of Cambridge
U.K.

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

Date: Mon, 18 Sep 89 09:10:58 PDT
From: Peter Scott <[e-mail]>
Subject: Re: Printing On a LaserWriter -- hints

*What* is this thread doing in SPACE Digest???  It seemed obvious that the
first posting was sent to the wrong group, but why is it being continued by
at least 3 posters in this group?  Or have I missed some magical esoteric
connection with space?

Peter Scott ([e-mail])

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

End of SPACE Digest V10 #81
*******************