Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V11_3/V11_380.ZIP/V11_380

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Subject: SPACE Digest V11 #380

SPACE Digest                                     Volume 11 : Issue 380

Today's Topics:
                Re: Apollo 12
             Sagan vs. asteroids
                Re: Apollo 12
             why there are no ETs
             Re: Manned mission to Venus
             Looking for a good telescope
          Free subscription to Supercomputing Review
             venus refrigeration
           Commercial Delta Launch Schedule
            Re: Apollo 12 launch decision
             Re: Manned mission to Venus
----------------------------------------------------------------------

Date: 9 May 90 12:16:19 GMT
From: usc!cs.utexas.edu!uwm.edu!srcsip!jhereg!wd0gol!newave![e-mail]  (John A. Weeks III)
Subject: Re: Apollo 12

In <[e-mail]> [e-mail] (Henry Spencer) writes:
> In general, the Apollo launch windows were about a month apart, since it
> was the position of the Moon that mostly dictated the windows.  ...
> I don't know what the situation was for Apollo 12, ....

The A&E TV Network recently ran the 4 part "Space Flight" series.  The
lightning strike during Apollo 12 is briefly mentioned.  They interviewed
one crew member that happened to be of Navy background.  He mentioned that
the CapCom asked their opinion as to whether or not to launch.  He replied
that the Navy would be happy to do NASA's all weather testing.  He went on
to say that it didn't take very long to regret that statement.  During the
interview, the crew said that they wanted to fly _that_ day because the
recycle was 30 days.

-john-

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

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

Date: 9 May 90 16:45:59 GMT
From: swrinde!zaphod.mps.ohio-state.edu!samsung!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Sagan vs. asteroids

In article <[e-mail].> [e-mail] (Joseph C. Pistritto) writes:
>> Everybody is talking about those asteroids, but some scientists, like
>> Carl Sagan, are now speaking against their exploitation.
>Then he's cracked...

One should remember that Chairman Carl seems to have heavy-duty ulterior
motives of the political kind these days, and that colors his views, to
put it mildly.  For example, his obsession with a joint US-USSR Mars
mission seems to focus on the "joint US-USSR" part, not the "Mars mission"
part.  Sagan's priorities in space now seem to be based on politics rather
than science and exploration.
--
If OSI is the answer, what is |     Henry Spencer at U of Toronto Zoology
the question?? -Rolf Nordhagen| uunet!attcan!utzoo!henry [e-mail]

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

Date: 9 May 90 17:05:13 GMT
From: amdahl!altos!altos86![e-mail]  (Jerry Gardner)
Subject: Re: Apollo 12

In article <[e-mail]> [e-mail] (Gregory N. Bond) writes:

>I have a question about launch windows.
>
>But for moon shots, well, it seems the moon is always in the same
>relative orbit, so a direct earth-moon window would happen once per
>day (as the earth rotated to the correct spot for launch).  So why is
>the window only open a few days per month?
>
>I am obviously missing _something_....
>


There are only a few days during a lunation that one would want to land on
the moon. Obviously, one wouldn't want to land around the time of new moon
because the earth-facing side is in darkness.  Likewise, one wouldn't want
to land near full moon because the sun is almost directly overhead and the
lighting is very flat and low contrast.

The best time to land is when the intended landing site has experienced
sunrise (or will experience sunset) within the last few days (or next few
days). The resulting lighting will be low-angle and the contrast will be
high, a desirable situation.

Of course, one could launch anytime if landing on the non-earth-facing
side of the moon were an option.  The problem with this is lack of direct
communication with earth (the only communication possible is through the
command module or through lunar orbiting communications satellites).


--
Jerry Gardner, NJ6A                    Altos Computer Systems
UUCP: {sun|pyramid|sco|amdahl|uunet}!altos86!jerry    2641 Orchard Parkway
Internet: [e-mail]                San Jose, CA  95134
Guns don't kill people, bullets do.                     [phone]

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

Date: 8 May 90 01:34:02 GMT
From: ogicse!blake!milton!acad!megalon![e-mail]  (Paul Baclaski)
Subject: why there are no ETs


It just occured to me that one of the possible reasons we have not discovered
extraterrestrial intelligence in the universe is that they have
created full fledged virtual reality systems and feel no need to
go exploring space because they have enough fun exploring the inner
space of their collective minds.


Paul
[e-mail]



Keywords: n

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

Date: 9 May 90 05:29:20 GMT
From: [e-mail]  (Edward Joseph Bennett)
Subject: Re: Manned mission to Venus

This is a very interesting topic. A large scale project to make
uninhabitable planets habitable is quite an undertaking. Especially when
we consider how difficult it just to take action on slight modifications
of our own climates on Earth. This would certainly make our current
problems such as S&L bailouts, budget deficits, and waste disposal seem
cheap. However, a patient and persistant program planned to span the
course of centaries and milleniums could bring about changes. Given the
rate of the population expansion on the Earth it may be worth while.
Problem is it is hard to get populations and politicians to think of
long term goals in the sense of decades let alone milleniums.  There
will be a sense why should I pay for this, I and will be dead long
before we have an impact.

I personally would like to see most of the peace dividend go towards
space developement after the deficit is brought under control. So lets
assume we could actually get governments to commit and stay committed to
such a project.

One problem with Venus is that in addition to the atmosphere being
composed of carbon dioxide and contributing to a huge greenhouse effects
the atmosphere is very dense. It has a pressure of 90 bars, 90 times
that of Earth at sea level. I would assume this would crush a human
being. (How does this compare to varios ocean depths and what can humans
deal with. It woukld seem that in addition to converting carbon dioxide
to oxgen we also need to get rid of alot of atmosphere. Mars on the
other hand has a pressure of 0.007 bars. It does not have enough of a
green house effect to keep heat in and is therefore too cold (while
venus is too hot). Granted Mars is further from the Sun and Venus closer
but both planets temperatures are more extreme than they need be.

A good approach would seem to be to take crabon dioxide from Venus and
transport it to Mars. This would lessen the Green house effect on Venus
(and Temp) and also lower atmospheric pressure. On Mars this would have
the opposite effect. Once Mars was warmed up. It would have a supply of
water in the forms of melted ice caps. I guess the question is (assuming
we can feasable transfer materials in sufficient quantities between
planets) can we strike appropriate balances on either planet to make
them habitable.

If someone who knows more about this than I can do some calculations.
Would the amount of Carbon dioxide needed to increase the temperature on
Mars to something reasonable also increase the atmospheric pressure to
something reasonable or would it be too great or too small. Would the
gravity of Mars be great enough to keep them there or would most quickly
escape. What effect would the fact that you will have to covert a
certain percentage of carbon dioxide to oxygen, what effect will this
have on greenhouse and temperature calculations.

I know this discussion has been focused on Venus but most of the
questions I raised could equally apply to Venus also.

Bottom line:

Assuming the technological capabilities and the resources to do such a
project.
The qusetion is would the enviroment be possible to build and would it
be stable.

For now we had better consider building closed enviroments for space
settlement.

Ed

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

Date: 9 May 90 17:22:27 GMT
From: oliveb!amdahl!rtech!ingres![e-mail]  (Sid Shapiro)
Subject: Looking for a good telescope

Hi folks, I hope this is the right place to ask this...
I'm looking for a good telescope for under $1000.  What are the
possibilities?  Are there any?  Must I go to $2000 or more?  Are there
any places that I might look for used scopes?

What I want is to see planets, moons of jupiter, rings of saturn, double
stars, other highlights in the sky.

Any recommendation?
Thanks much,
--
Sid Shapiro -- Ingres Corporation (nee Relational Technology, Inc.)
[e-mail]  (nee rtech.com)              [phone]

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

Date: 6 May 90 21:58:52 GMT
From: ulysses!atti07!althea![e-mail]  (Sarah Stambler)
Subject: Free subscription to Supercomputing Review


SUBJECT LINE:
FREE SUBSCRIPTION TO SUPERCOMPUTING REVIEW
----------------

FREE three month trial subscription to SUPERCOMPUTING REVIEW.

The leading magazine on high-performance computing,
SUPERCOMPUTING REVIEW, is offering a three month trial
subscription at no charge (a $36 value).

To receive a free subscription reply via modem to their BBS:

Call 212-749-8427, 24 hours, 1200/2400-8-N-1.

To sign on, enter SUPER BBS for first & last name and GO for
password.

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

Date: 8 May 90 20:35:27 GMT
From: zaphod.mps.ohio-state.edu!van-bc!ubc-cs!fornax![e-mail]  (Zeke Hoskin)
Subject: venus refrigeration


    The basic idea isn't at all silly.  Recall your basic refrigerator
design: compress a fluid, which heats it. Radiate the heat. Expand the
fluid, which cools it. Absorb heat from the thing you want to cool.
    In the case of Venus, a huge simplification looks possible by using
the atmosphere as working fluid.
      ---------------------------------------------------
      |        environment to be cooled                 |
      |                                                 |
check >==================================================(PUMP)
valve |        cooling coil                             |in  out
      ---------------------------------------------------

    Simply make a strong insulated box, run a coil through it, and
put a check valve at one end and a pump at the other. Pump out the
coil, and Venusian atmosphere expands into the coil and cools.  Since
the exhaust is back into the atmosphere, no hot-end radiator is needed.

    While the basic thermodynamics aren't open to question, there will
be practical problems:
   Making a box that is strong enough and a good enough insulator
   Making the plumbing stand up to Venusian atmosphere
   Making a pump and motor that can run outside the box. (The system
might be made to work with them inside, but at a temperature
ratio of about 4:1, if they were less than 75% efficient they would
give off more heat than the coil was removing.)
   Making it all light enough to send to Venus.

   I'm not proposing that we send one of these anywhere this year. I
am suggesting that somebody with a Venus-environment simulator build
one and try it out. In fact, I'd be surprised if nobody were doing
just that already. But unpleasant surprises arent rare enough....

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

Date: 9 May 90 22:29:39 GMT
From: usc!elroy.jpl.nasa.gov!aero![e-mail]  (Thomas F. Smith)
Subject: Commercial Delta Launch Schedule

Commercial Delta launches by McDonnell Douglas Space Systems Co.
from Launch Complex 17 at Cape Canaveral Air Force Station, Florida.

Note: INMARSAT-F2 and CONTEL/ASC
could be switched with each other based
on vehicle or payload hardware availability.

          COMMERCIAL DELTA DATES

        INSAT-1DR:      12 JUN 90
        BSB-R2:         13 AUG 90
        INMARSAT:       15 OCT 90
        NATO IVA:       10 DEC 90
        INMARSAT-F2:    14 FEB 91
        CONTEL/ASC:     14 MAR 91
        AURORA II:       1 MAY 91
-----------------------------------------
--
This space reserved.                                     Space Not Reserved.
Space Commercialization Office, Space Systems Division, Los Angeles AFB, CA.

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

Date: 9 May 90 07:12:52 GMT
From: pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!samsung!munnari.oz.au!metro!cluster![e-mail]  (Raymond Lister)
Subject: Re: Apollo 12 launch decision


There is an excellent account of the decision to launch Apollo 12 in
"Apollo: The Race to the Moon", by Charles Murray & Catherine Cox.

The important points are:

1. The weather was marginal, but within launch rules.
2. When drawing up those launch rules (months, if not years, before the
   launch) nobody had realized that the ionized exhaust of the Saturn V
   would ground it.

The above book is full of great engineering war stories.  I recommmend it.

Raymond Lister
Department of Computer Science, F09
University of Sydney
NSW  2006
AUSTRALIA

Internet: [e-mail]
JANET:      munnari!cs.su.oz.AU!ray@ukc (if you're lucky)

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

Date: 8 May 90 22:46:27 GMT
From: asuvax!hrc!gtx![e-mail]  (Alan Filipski)
Subject: Re: Manned mission to Venus

If you really want to know about a manned mission to Venus, read
"Semicentennial:  Baltimore-to-Venus Attempt" in Science News v.114
n.5, July 29, 1978.

This is a marvelous true account about three young men (20-30 years
old, not kids) who, caught up in the can-do spirit of the times (1928),
built a manned Venus probe in a garage in Baltimore.  It was made out
of varnished sailcloth stretched over angle iron, and was "powered" by
a paint sprayer that shot vaporized gasoline through tubes containing
spark plugs.  It had glass portholes and a silk parachute.  It didn't
have a guidance system, but they figured that they could hit venus by
taking real careful aim.

It did about what you would expect when they tried to launch it.  The
quote from one of the guys was: "I never saw so much fire in my life."
Somehow, the "pilot" who was bolted inside failed to be burnt to a
crisp or blown up.

Anyway, to make a long story short, they figured that it would cost
about $10,000 to do the job right, and their wives were against the
whole project anyway, so they gave up.

An awe-inspiring story.


  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 ( Alan Filipski, GTX Corp, 8836 N. 23rd Avenue, Phoenix, Arizona 85021, USA )
 ( {decvax,hplabs,uunet!amdahl,nsc}!sun!sunburn!gtx!al         [phone] )
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

"Gully Foyle's my name,
and Terra is my nation,
deep space my dwelling place,
the stars my destination."

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

End of SPACE Digest V11 #380
*******************