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Date: Tue, 10 Oct 89 04:22:37 -0400 (EDT)
Subject: SPACE Digest V10 #131

SPACE Digest                                     Volume 10 : Issue 131

Today's Topics:
             Re: Shuttle-Centaur
    Re: Ozone ( was Re: NASA Headline News for 09/29/89 )
            RE: Re: Concord, Nasp, shuttle
             Re: Shuttle-Centaur
            astrodynamic software
     Re: Galileo Jovian atmospheric probe -- is it sterilized???
            Re: RTGs, shuttle launch risks
    RE:  Happy Birthday, Robert Goddard and Konstantin Tsilkovsky.
         Orbital Rendezvous (was Re: Shuttle-Centaur)
                 BioSphere II
    Re:  Happy Birthday, Robert Goddard and Konstantin Tsilkovsky.
----------------------------------------------------------------------

Date: 8 Oct 89 02:26:21 GMT
From: attcan!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Shuttle-Centaur

In article <[e-mail]> [e-mail] (Paul Rodman) writes:
>>>I heard the original plan had DUMP VALVES for the Centaur fuel...
>>Yup.  Most airliners with significant problems will dump fuel before landing
>>as well, for much the same reasons...  What's the big deal?
>...
>      - An airliner dumps JP4. I presume the Centaur dumps potent fuel
>        + oxidizer (not hypergolic I trust!). What is the probability
>        of ignition in the presence of RCS thrusters, hot airframes,
>        SRBs...

Centaur would be dumping liquid hydrogen and liquid oxygen.  Oxygen doesn't
ignite.  Hydrogen can be treated much like JP4, despite some of the scare
stories you see in the media.  (Incidentally, JP4 is military jet fuel; an
airliner would be dumping something like Jet A.)  No, they're not hypergolic.
Dumping would probably be done late in the abort, at a time when the SRBs
are gone and the RCS thrusters are not useful.  Ignition doesn't seem too
likely, and I wouldn't think it would be automatically disastrous even if
it did happen.

>      - You are awfully busy on a launch abort, are you going to
>        allow a computer to decide when to dump? Yech.

The decision would undoubtedly be manual.  Most of the nasty decision-making
is early in the abort (engine problems, trajectory) or very late (landing);
dumping would probably be done in between, in glide.

>I'm not saying it can't (or shouldn't) be done, it just seems like
>more dicey scenerios are added to an already hazardous activity...

The orbiters are very safe sitting on the ground.  Getting results requires
taking risks.

>... Seems like the correct approach
>would be to have a Space tug (+ IUS on the probe too) to kick things
>out of earth orbit. Refuel the tug from unmanned tankers, please.

This would undoubtedly be the correct approach.  There is a small problem:
the Tug died long ago and was not available.  Centaur was.
--
A bit of tolerance is worth a  |     Henry Spencer at U of Toronto Zoology
megabyte of flaming.           | uunet!attcan!utzoo!henry [e-mail]

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

Date: 8 Oct 89 01:54:56 GMT
From: attcan!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Ozone ( was Re: NASA Headline News for 09/29/89 )

In article <[e-mail]> [e-mail] (Iain Davidson) writes:
>He told me , beleive it or not, that the ozone/world would "fix/correct"
>  itself over time.  This is due to the supply of Algae in the world's
>  ocean-- The supply will increase if the hole grows bigger, and increase
>  production of what's needed for repairing the hole...

I think either he or you has confused the ozone hole (lack of ozone over
Antarctica) with the greenhouse effect (excess CO2 worldwide).  There are
no algae in Antarctica to react to the ozone hole, and their most probable
reaction to it would be death, which won't help.
--
A bit of tolerance is worth a  |     Henry Spencer at U of Toronto Zoology
megabyte of flaming.           | uunet!attcan!utzoo!henry [e-mail]

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

Date: Thu, 5 Oct 89 16:51:35 PDT
From: [e-mail] (Richard Killion)
Subject: RE: Re: Concord, Nasp, shuttle
Cc: [e-mail]


 >In article <[e-mail]> [e-mail] (Eugene Miya) writes:
>>It's not clear to me that SSTs will ever be economical
>>forms of transport.

prism![e-mail]  (Olivier Schreiber of  Georgia Institute of
Technology) then responds:

>Indeed, it may not do a businessman any good to shave a
>few hours of flight time off his schedule if he spends
>two hours in urban traffic
>to get in and out of the airports of departure and
>destination.
----
The best time for getting from L.A. to Tokyo is about 10 hours (let's
add 2 hours on both sides for traffic to get to 14 hours).   As a
traveller to Tokyo, I know that a 6 hour flight is a big difference
compared to 14!   I don't consider the extra 8 hours to be a *few
hours* and could do without them.

Tokyo is CLOSE, compared to most of the Pacific Rim countries.  There
are longer flights such as  to Australia or the ASEAN countries.  The
urban traffic time is just minor overhead.

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

Date: 7 Oct 89 20:24:03 GMT
From: telesoft![e-mail]  (Roger Arnold @prodigal)
Subject: Re: Shuttle-Centaur

[e-mail] (Joseph  Brenner) writes:
> So what was the problem with launching the Centaur dry and fueling
> it up in orbit?
> [..]
> (My guess: You've got to boost the fuel somehow, and putting it in
> a different shuttle launch just moves the risk to another time.
> Boosting the fuel with an unmanned rocket might work but in
> those days NASA's policy was to do everything with the shuttle.
> Also, this gets back to the rendevous in orbit issue, which
> I gather is considered too tough by NASA, despite experience with
> Gemini, Apollo, Skylab and Apollo/Soyuz.)
>
> -- Joe B.

One method that was proposed was to fuel it from residual fuel in the
ET.  (It's just as easy to carry the needed mass of Centaur fuel in
the ET as in the Shuttle, since the ET can go all the way to orbit
with the Shuttle, with a slight gain in net payload over the launch
path that causes the ET to reenter in the Indian Ocean).

Problems:

1) It's not easy to transfer liquid fuels in microgravity.  To be
   able to scavange fuel from the ET, it would probably have been
   necessary to add an LH2/LOX thruster to the Shuttle, and keep
   Shuttle & ET under continuous low acceleration during the fuel
   transfer period.  This was too radical a development for NASA,
   even though it would have meant increased Shuttle payload.

2) It would have left the ET in LEO.  Horrors!  Poor little NASA
   couldn't see its way to develop the systems needed to prevent
   an uncontrolled ET reentry as its orbit decayed.

In the two+ year hiatus following the Challenger accident, and for
the same money spent, the NASA of the 60's could probably have
developed the unmanned Shuttle-C, making the safety issues of a
Shuttle Centaur irrelevant.  (And, incidently, restoring a Saturn
class heavy launch capability.)  The NASA of the 80's...

No, I won't say it.  I'm letting my disillusionment get the best of
me.  I HATE whining.

- Roger Arnold                ucsd!telesoft!roger

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

Date: 8 Oct 89 08:12:49 GMT
From: lightsabre![e-mail]  (Rick Kwan)
Subject: astrodynamic software

I have been toying off-and-on with computational astrodynamics for
several years.  It's "on" time again...  so I thought I'd throw some
questions to those of you with better stamina for such things:

    --    Is there any well-accepted public domain source code for
    handling multi-body problems (like several planets orbiting
    a star)?  (What do universities do for this?)

    --    Is there a standard machine-parsable ephemeris format for
    interplantary missions?  My assumption is that the same
    format might apply both to planets and to spacecraft.

    --    Any recent books on astrodynamics?  All my stuff dates back
    to the mid-70s or earlier.  (I assume the principles haven't
    changed; but there's been a tendency lately to use computer
    programs to illustrate problem solutions.  With the latest
    emphases on "scientific visualization," I expect this even
    more.)

    --    Has anyone taken RAND Corp.'s ROCKET program and recoded
    into C? ;-)


Rick Kwan
Sun Microsystems - Intercontinental Operations
[e-mail] or [e-mail]
    Rick Kwan (aka Obi-Kwan Kenobi)
    Sun Microsystems - Intercontinental Operations
    [e-mail] or [e-mail]

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

Date: 8 Oct 89 07:33:30 GMT
From: agate!shelby!portia!hanauma![e-mail]  (Joe Dellinger)
Subject: Re: Galileo Jovian atmospheric probe -- is it sterilized???

In article <[e-mail]> [e-mail] (John Woods) writes:
>Or do you somehow think that Earth life is so obviously superior to
>anything Jupiter can crank out that Jovian life can't possibly
>measure up?
>--
>John Woods, Charles River Data Systems, Framingham MA 508-626-1101
>...!decvax!frog!john, [e-mail], ...!mit-eddie!jfw, [e-mail]

Well, I would tend to agree with you, but there are precedents to
the contrary. South America is a much larger continent than North
America, so you would expect it to be able to "hold its own"
evolutionarily against invaders... and yet when the isthmus of Panama
formed (quite recently geologically speaking) the North American mammals
almost _immediately_ spread South and _totally wiped out_ all the native
South American mammals.

I know of only one South American mammal that managed to make the trip
the other direction --- the Opossum. The problem was that South America,
though possessing a large, diverse ecosystem, was still sticking with
marsupials as the dominant type of mammal.

In the fossil record there is a sudden spectacular explosion of diversity
near the beginning of the paleozoic. What was Earth life doing for the
first few billion years of life (MOST of the history of life) when "not
much" appears to have been happening? My guess is it was meta-evolving:
evolution towards genetic systems that are able to evolve more efficiently.
For example, the genetic code is arranged in such a way that point mutations
tend to change one amino acid for a chemically similar one. (Evolution is
then more like a "gradient search" algorithm instead of a "monkey attempting
to write Hamlet" one.)

To give some idea about just how efficient evolution on Earth has become,
the EYE, far from being a lucky miracle of evolution, appears to have
evolved AT LEAST TWICE, independently, complete with retina, iris, lens,
etc! The best guess is that the last common ancestor between humans and the
Octopus preceded the evolution of the eye by a wide margin, and yet the
Octopus possesses an eye very similar to our own in form and function.
This might be taken as evidence against evolution, but biological evidence
supports the notion it really WAS independently evolved. When you look at
all the "technical specifications" the octopus eye is very different,
while all vertebrates' eyes are essentially the same.

From the geological record, it appears that the HARD part was coming
up with multi-cellular life. After that, EVERYTHING else - shells,
nervous systems, 4-chambered hearts, large brains --- is trivial.
While life per se may be common, I suspect Earth life got lucky and
evolved a system that permitted especially efficient evolution. That's
why we're here launching space probes against them, instead of vice
versa.
\    /\    /\    /\/\/\/\/\/\/\.-.-.-.-.......___________
 \  /  \  /  \  /Dept of Geophysics, Stanford University \/\/\.-.-....___
  \/    \/    \/Joe Dellinger [e-mail]  apple!hanauma!joe\/\.-._

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

Date: 8 Oct 89 03:30:32 GMT
From: portal!cup.portal.com![e-mail]
Subject: Re: RTGs, shuttle launch risks


While this is not particularly germane to this group, the average
1000 MW coal fired power plant costs 51 people their lives.  Most
of those are transportation workers (rail road people) killed while
transporting the coal and ash.  These numbers do not reflect any
early deaths from stack gases or heavy metals leaching from the
ash piles.

BTW hydroelectric plants are not free from risks either.  Thirty
years ago the dam at Vionia (sp?), Italy, failed and killed
20 000 people by flushing the village off of the face of the
opposite hill.  The number is approximate because few of the bodies
were recovered.

                Jerome Vollborn

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

Date: Sun, 8 Oct 89 11:41:27 CDT
From: [e-mail] (abrams)
Posted-Date: Sun, 8 Oct 89 11:41:27 CDT
Subject: RE:  Happy Birthday, Robert Goddard and Konstantin Tsilkovsky.


In Space Digest #124, Larry Klaes sends
>On October 4, 1857, Konstantin Tsilkovsky,
>the Soviet founder of modern rocketry, was born exactly one hundred
>years to the day when SPUTNIK 1 was launched.

Asimov's Biographical Encyclopedia of Science and Technology lists
Tsiolkovskii's birthday as September 17, 1857 and Asimov even mentions
that 100 year anniversary launching being late.  I'm not saying Larry
is wrong...but someone is.  Any other sources out there?

                    Steve Abrams
                    [e-mail]

"Mankind will not remain tied to Earth forever"

                    -- Tsiolkovskii's tombstone

(not as poetic as the "cradle" interpretation, but closer to being a
transliteration)

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

Date: 8 Oct 89 18:49:11 GMT
From: rochester![e-mail]  (Brian Yamauchi)
Subject: Orbital Rendezvous (was Re: Shuttle-Centaur)

In article <[e-mail]> [e-mail] (Joseph  Brenner) writes:
>Also, this gets back to the rendevous in orbit issue, which
>I gather is considered too tough by NASA, despite experience with
>Gemini, Apollo, Skylab and Apollo/Soyuz.)

Really?  Why does NASA think orbital rendezvous is so difficult?  A
shuttle already accomplished this to recover a satellite.  Besides,
how do they plan to build Freedom without being able to rendezvous in
orbit?

_______________________________________________________________________________

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

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

Date:     Sun, 8 Oct 89 18:33 EST
From: <[e-mail]>
Subject:  BioSphere II

        Has anyone heard anything lately about the Arizona (?) BioSphere
II project?  I believe they were to have entered by now.  Are they
surviving?  Any major/minor environmental problems?

        I still think that this project is one of the most exciting
ongoing experiments being carried out at this time.  Its effects on long-term
survival in closed systems (i.e. space) will hopefully be phenomenal.

 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
|  Arnold Gill                          |
|  Queen's University at Kingston       |
|  BITNET:    gill@qucdnast             |
|  INTERNET:  [e-mail]  |
 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

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

Date: 9 Oct 89 02:42:20 GMT
From: jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re:  Happy Birthday, Robert Goddard and Konstantin Tsilkovsky.

In article <[e-mail]> [e-mail] (abrams) writes:
>>On October 4, 1857, Konstantin Tsilkovsky,
>>the Soviet founder of modern rocketry, was born...
>Asimov's Biographical Encyclopedia of Science and Technology lists
>Tsiolkovskii's birthday as September 17, 1857 and Asimov even mentions
>that 100 year anniversary launching being late...

Be careful.  The dates are slippery.  Russia was on the old Julian calendar
well into the 20th century; the switch to the modern Gregorian calendar
was much more recent than we're used to.  The Soviets also tend to cite
dates as if the switch had been considerably earlier, which adds to the
confusion.  This is why the anniversary of the "October Revolution"
is celebrated in November.

I thought to hit Willy Ley's "Rockets, Missiles, and Men in Space"
for a check.  (This is THE BEST history of the early space age, written
by someone who was there for most of it.  In particular, he knew and
corresponded with Tsiolkovsky.)  Ley cites Tsiolkovsky's birthday as
5 Sept 1857 Julian, 17 Sept Gregorian.  He says that it was widely
reported in the West that the first launch attempt for Sputnik would
be made on the anniversary of Tsiolkovsky's birth, but nothing visible
happened that day.

Incidentally, there is no one-to-one mapping from Cyrillic characters to
Latin ones, and so there is some debate about the spelling of Tsiolkovsky's
name.  He himself spelled it "Ziolkovsky" when writing in Latin-alphabet
languages, according to Ley, although "Tsiolkovskii" is a more phonetic
rendering.
--
A bit of tolerance is worth a  |     Henry Spencer at U of Toronto Zoology
megabyte of flaming.           | uunet!attcan!utzoo!henry [e-mail]

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

End of SPACE Digest V10 #131
*******************