Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_0/V13_088.TXT

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Subject: SPACE Digest V13 #088

SPACE Digest                                      Volume 13 : Issue 88

Today's Topics:
               Ultimate Weapon
              Galileo Update - 01/22/91
           Spaceflight: Soviet Moon Program
              Re: 2 dimensional objects
            Speed of the Moon's terminator
             Re: THE BLUE PLANET
              Re: 2 dimensional objects
          Planetary Rover Research Projects
           Re: space news from Dec 17 AW&ST

Administrivia:

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

Date: 22 Jan 91 15:29:55 GMT
From: unmvax!uokmax!d.cs.okstate.edu![e-mail]  (Roland Stolfa)
Subject: Ultimate Weapon

Fellow spacers, lend me your eyes for a few seconds...ok, minutes.
I would like to ask a few questions about black holes.  As this progresses,
you will see how it relates to my subject line.

1.    Are black holes stationary in space.  Ie, if you have a black hole
    next to a star, does the black hole move at all, or does the
    star just revolve around the black hole?  Further, can a black
    hole move?

2.    Do we have any theories about how much matter you would have to
    have in any one place to generate a black hole?

If both of the two previous questions can be answered "yes", then consider
the following Ultimate Weapon.

A.    Take two areas and collect in each one half of a black hole's mass.
    These two areas should be far enough appart that they will not be
    pulling each other together, yet.

B.    Once the mass has been achieved, start both pieces in motion
    towards an "enemy", while also moving the pieces towards each
    other (see below).

        1/2 bh\
               \
            >bh------> enemy
               /
        1/2 bh/

C.    Arrange it so that the two pieces collide and form our black
    hole before reaching the "enemy", hopefully far enough away
    from "us" to not cause us any problems.  If it needs some energy,
    make the collision point some star that already has a good
    chunk of the mass, as well as the energy that might be needed.

D.    Once the black hole has been formed, it could travel along
    (Newtons's law ???), and quite simply suck the entire solar
    system of the "enemy" to oblivion.

Advantages:
    Something so massive would probably not be too easy to stop,
    it would be un-defuseable (unlike a bomb), would be fairly hard
    to detect (unless you were looking for it), and might even
    do the job.

Disadvantages:
    For the time being, impossible to accomplish (let's hope it
    stays that way).

Another question,

3.    Would this be a way of forcing a "worm hole" in space?  In other
    words, from the point at which the black hole became a singularity,
    as it travels, would it permanently warp space, or would such
    a massive object only affect it's own local environment?

Interested minds, fuzzy with physics, want to know.  :-)

Roland Stolfa                Internet:    [e-mail]
Computer Science Department        Disclaimer:    You've lost your mind
219 Math Sciences Building                if you think anyone
Oklahoma State University                speaks for this place!

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

Date: 22 Jan 91 18:53:00 GMT
From: swrinde!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update - 01/22/91


                            GALILEO STATUS REPORT
                              January 22, 1991

     Yesterday's activities on the Galileo spacecraft were all successfully
completed.  The sun acquisition activity and science memory readout for the
DDS (Dust Detector) and MAG (Magnetometer) instruments were performed as
planned.

     Today, the planned CDS "A" (Command Data Subsystem) memory readout
activity is in process and proceeding well.  Tomorrow, another of the stored
sequence periodic sun acquisitions will be performed to maintain sun point
attitude.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date: 22 Jan 91 11:56:58 GMT
From: van-bc!rsoft!mindlink![e-mail]  (Bruce Dunn)
Subject: Spaceflight: Soviet Moon Program

From "Spaceflight", January 1991

The Moon Programme That Faltered

     This is a two page article with diagrams on the Soviet moon program in the
1960s.  Information is from a Spaceflight interview with Vasili Mishin, who was
the Soviet space program chief designer after the death of Korolyov in 1966,
until he was dismissed in 1974 after repeated failures to successfully launch
even the booster stages of the moon vehicle.
     The moon vehicle was a five stage vehicle, with the lower three stages
termed the N-1, and the upper two stages the L-3.  The first to fourth stages
used LOX and kerosene - propellants for the fifth stage are not given; stage 1
had 30 motors, stage two 8 motors, and stage three 4 motors, while stages four
and five had one motor each.  The first two stages were steered by differential
throttling of the engines, while the rest had conventional gimballed thrust.
The fifth stage was topped by a lunar lander (termed "lunar cabin") and by a
"lunar orbital cabin" (a modified Soyuz).  The lunar lander had one engine for
both descent and ascent, burning UDMH and nitrogen tetroxide.
     In operation, the first three stages were to place the upper stages in
earth orbit. The fourth stage would be fired to give a lunar trajectory
followed by the fifth stage to give lunar orbit insertion.
     The article implies a crew of two, of whom one would remain in lunar orbit
in the Soyuz and the other who would land.  Transfers between the Soyuz and
lander were to be by spacewalk, as there was no docking arrangement for the two
vehicles.  Return to earth was to have been by the Soyuz, using a 1 skip
atmosphere reentry (a dip into the atmosphere to lose velocity, followed by an
upward skip to allow radiative cooling of the reentry vehicle, followed by
final reentry).
     "According to Mishin the main reason for the failure of the lunar
programme was a lack of funds."  Mishin stated:  "The Americans spent $25
billion but we spent only three billion or even less.  The United States spent
up to six billion per year... [Our budget] was only half a billion a year at
the peak of the programme in 1967/68."
     The article goes on to detail failed test flights of the N-1/L-3 in 1969
(explosion after 70 seconds), two subsequent launch pad explosions, and a final
inflight explosion in 1972.  "Two more rockets had been fully assembled and
readied for flight but in 1974 the programme was cancelled and Mishin dismissed
as Chief Designer". "According to Mishin, the N1/L3 would have had to have
successfully flown four or five times before a manned launch was attempted."


The monthly magazine "Spaceflight" may be received worldwide by mail through
membership in the British Interplanetary Society.  Details may be obtained
from:

British Interplanetary Society
27/29 South Lambeth Road
London  SW8 1SZ
England

--
Bruce Dunn   Vancouver, Canada    [e-mail]

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

Date: 23 Jan 91 20:46:51 GMT
From: hpl-opus!hpnmdla!hpsad![e-mail]  (Erik Kilk)
Subject: Re: 2 dimensional objects


I remember Carl Sagan's TV series on the PBC devoted a segment on such
flat people.  I can't remember the series name, but it might have been
"Universe." He animated flat people as disks and their homes had just
walls (drawn as lines like in a set of house plans).

The point was that us three dimensional people could look into all the
rooms of their homes (even if the doors were closed), see all the flat
people whether they were inside or not, and could even see inside their
bodies and walls.  But the flat people themselves couldn't see past
their walls, each other, or their skin.

Sagan then took a 3d apple and set it down on the flat world.  He noted
that in the point of view of the flat people, the apple just appeared
out of no where and looked like a few separate spots (only the points
where the apple touched the flat land were visible to the flat people).

My memory fades, but I believe he asked questions like:

What if the apple was set upon a flat person?  It would appear right in
his body.

What if we picked up one of the flat people?  That person would disapear from
view of all his friends.  He would be able to look down upon the flat world,
see all his friends, see inside all their houses, see in their bodies, etc.
etc.  It would boggle his mind!

I believe all this was to suggest that our 3rd dimension is to the flat
people as a 4th dimension might be to us!

Erik

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

Date: 25 Jan 91 04:30:30 GMT
From: uvaarpa!murdoch!bessel.acc.Virginia.EDU![e-mail]  (Christopher R. Mullis)
Subject: Speed of the Moon's terminator

Can anyone provide a formula to calculate the angular velocity of the lunar
terminator's advance at a given lunar latitude.

I have posted a similar request on sci.astro but so far there have been no
replies.

Thanks in advance.
---------------------------------------------------------------------
Christopher R. Mullis, University of Virginia
USPS:      Astronomy Department, Charlottesville, VA  22903-2475  USA
Internet:  [e-mail]       ---------------------------------
Voicenet:  804-971-3895             | Fan Mountain Observatory      |
FAX:       [phone]             | Leander McCormick Observatory |
---------------------------------------------------------------------

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

Date: 19 Jan 91 16:55:15 GMT
From: rex!wuarchive!uwm.edu!src.honeywell.com!msi.umn.edu!cs.umn.edu!kksys!wd0gol!newave![e-mail]  (John A. Weeks III)
Subject: Re: THE BLUE PLANET

In article <[e-mail]> [e-mail] (Daniel Fischer) writes:
>>> ...most IMAX theatres don't show this thrilling feature much anymore,

> A technical question: there are two kinds of giant-screen cinemas, one with
> a flat screen ('5 stories high' or so go the ads), the other one working
> inside a planetarium dome - which one of these is the actual 'IMAX' system?

An IMAX screen is a section of cylinder, while the OMNIMAX screen is part of
a sphere.  IMAX is an older system, OMNIMAX is fairly new.  Both systems are
covered by pattens, and the words IMAX and OMNIMAX are trademarks.

> If so, where are there less distortions from the point of view of an
> observer right in front of the screen resp near the center of the dome?

The best seats are as close to the center of the seats as possible.  The
biggest source of distortion are theatres that show IMAX films in OMNI
theatres.  The edges of the screen are very blury, especially if you are
sitting in the edge seats.

-john-

--
===============================================================================
John A. Weeks III               [phone]               [e-mail]
NeWave Communications                 ...uunet!rosevax!tcnet!wd0gol!newave!john
===============================================================================

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

Date: 20 Jan 91 09:45:26 GMT
From: magnus.ircc.ohio-state.edu!zaphod.mps.ohio-state.edu!sdd.hp.com!news.cs.indiana.edu!ariel.unm.edu!pprg.unm.edu!topgun!mustang!nntp-server.caltech.edu![e-mail]  (Todd A. Brun)
Subject: Re: 2 dimensional objects

In article <[e-mail]> [e-mail] (Jason J. Levit) writes:
>In article <[e-mail]> [e-mail] (Jonathan A Bishop) writes:
>>[e-mail] (Jason J. Levit) writes:
>>
>>>  2 dimensional objects (beings?) without any height?  WHAT?  Is this
>>>  plausible in a 4 dimensional universe?
>>
>>     What do you mean by 4 dimensional?  Three of space and one of time or
>>four of space?  Either way, our universe may have more dimensions of space
>>than we can perceive, so two dimensional creatures in a four dimensional
>>(or higher) universe are just as plausible as three dimensional creatures.
>
>  3 of space, 1 of time.  These guys were claming that these creatures
>  didn't have any height.  I find that very hard to believe!
>
I hesitate to point this out, but using Star Trek (even from the Next
Generation) as a source of physical insight is roughly like using Dan Quayle
as a source of political wisdom.  If we could only beam him into a bunker
with Saddam Hussein, we could probably assure a bloodless victory...

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

Date: 21 Jan 91 05:54:18 GMT
From: rochester!sol![e-mail]  (Brian Yamauchi)
Subject: Planetary Rover Research Projects


I'm interested in compiling a list of the planetary rover projects
(government, industry, and academic) that are currently active.  I'm
familiar with the efforts at JPL (Miller/Wilcox), CMU (Ambler), RPI
(CIRSSE), and MIT (Brooks), and I would be interested in hearing about
any other ongoing research.

I'm interested in references to any papers (or people) connected with
the following groups:

    1) Martin-Marietta

I saw their rover featured in Aviation Week.  Does anyone know if
they've published anything?

    2) NASA Ames Research Center

I've heard (second-hand) that there is some rover research being
conducted here.  Does anyone have the details?

    3) Rockwell

I just saw a mention of a Rockwell microrover plan in the current
issue of Ad Astra.  I'm curious whether this is just a design or if
actual robots and/or simulations have been buit.

    4) Any others I've missed

If there is sufficient interest, I will post the completed list.

                Thanks in advance,
--
_______________________________________________________________________________

Brian Yamauchi                University of Rochester
[e-mail]        Computer Science Department
_______________________________________________________________________________

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

Date: 21 Jan 91 10:34:58 GMT
From: zaphod.mps.ohio-state.edu!rpi![e-mail]  (Michael V. Kent)
Subject: Re: space news from Dec 17 AW&ST

In article <[e-mail]> [e-mail] (John McKernan) writes:
>reliable, smaller launchers such as the Delta, if NASA were willing to
>accept a little more risk of launcher failure. Given that putting men
>into orbit is still a very primitive, chancy business, I think NASA
>should acknowledge and accept that risk in any case.


Getting NASA to accept the risk is not your problem.  Your problem is getting
Dan Rather and hence John Q. Public to accept the higher risk.  The U. S.
manned space program almost ceased to exist in 1986 due to 1 failure in 25
flights.  Anything riskier than 1 in 100 will probably never be allowed to fly.
I'm afraid we're going to have to live with that constraint, as limiting as it
is.  For that reason, the Shuttle will probably be our only manned vehicle
this decade.

Michael Kent                                           [e-mail]

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

End of SPACE Digest V13 #088
*******************