Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V11_4/V11_413.ZIP/V11_413

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Subject: SPACE Digest V11 #413

SPACE Digest                                     Volume 11 : Issue 413

Today's Topics:
             Re: Spectroscopy on the HST
              Re:  SPACE Digest V11 #396
              Galileo Update - 05/16/90
              Terraforming Venus
    Re: Terraforming Venus (was: Manned mission to Venus)
             Measurement in space
             What was NOTSNIK ???
----------------------------------------------------------------------

Date: 16 May 90 15:26:35 GMT
From: usc!elroy.jpl.nasa.gov!jato!mars![e-mail]  (Ron Baalke)
Subject: Re: Spectroscopy on the HST

In article <[e-mail]> [e-mail] (Chris Paulse) writes:
>
>I've seen mentioned in the bulletins regarding the Hubble Space
>Telescope the Goddard High Resolution Spectrograph.  Would anyone be
>so kind as to fill me in on what this apparatus is (will be)
>capable of doing?
>
The Goddard High Resolution Spectrograph is designed to observe ultraviolet
radiation from objects, and will tell the composition, temperature and
density of stellar objects and vast gas clouds thoughout the universe.

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

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Resent-Date:  Wed, 16 May 90 13:45:05 EDT
Resent-From: Harold Pritchett <[e-mail]>
Resent-To: Space discussion group <[e-mail]>
Date:     Wed, 16 May 90 03:43 CST
From: Kevin 'Charlie' Brown <[e-mail]>
Subject:  Re:  SPACE Digest V11 #396
Original_To:  JNET%"space@tcsvm"
Original_Cc:  CSCI31F7

This message  was originally submitted by  CSCI31F7@UHCL2 to the SPACE  list at
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----------------- Message requiring your approval (172 lines) -----------------


In message <[e-mail]>, [e-mail] writes:
>>
>> >  What are the odds of two civilizations existing at the same time?
>> >Earth is at least 3 billion years old, and we have been using radio for
>> >maybe 100 years. Assuming no change in the world population trends we
>> >will no longer have resources for space exploration in another 100
>> >years. That leaves a very small window for an intelligent race to
>> >discover us.
>>
>How fortunate for them.

Sorry, but if I were a spacefaring race, *I* wouldn't be afraid of a
planet-bound civilization when all I had to do was drop a few rocks on them
if they became a threat...

>> This overly pessimistic and has many flaws. First, I thought one of the
>> reasons for developing space is to expand are supply of resources. In
>> our solor system there are huge supplies of metals, energy, etc., etc.
>> Second, Assuming no change in world population trends may be flawed. The
>> US for example in the past century has went from large population growth
>> to negative population growth (Our small population growth is from
>> immigration). Likewise most other 'Developed nations' have. It is only
>> third world nations that have a population boom.
>>
>The current, and forever into the future trend in world population is up.
>Fortunately, this too is a self-limiting process. Rampant disease, grind-
>ing poverty, and starvation will reduce the total number of humans on
>Earth.

This assumes that humans are unable to control their ability to reproduce,
which has been demonstrated NOT to be the case.  Already, there are several
countries in Europe that have achieved zero population growth (Switzerland,
Italy, and Greece to name a few) WITHOUT disease, poverty, and starvation
being the primary driving forces.  As technology spreads and increases, the
population will stabilize because in a technological society, children are
a hinderance, not an asset.

>> Lets treat Earth as a typical planet. It seems that civilizations will
>> becoming into space technology just as many other problems are starting
>> to become acute. The question is what is the probability that a
>> civilization will adress these problems and solve them before it is too
>> late. (avoid blowing themselves up, destroying the enviroment, and
>> overpopulating themselves). I personally would say the probability of
>> this is at least 1 in 10 civilizations would make it and extend their
>> window well beyond the 100 years you give them.
>>
>After all, look at how well we're doing at it. If Earth is taken as a
>"typical planet," then not only is the human race on its way to quiet
>oblivion, but the entire universe, and all the beings in it are as well.

It is possible that mankind is on the road to self-destruction, but recent
events seem to indicate otherwise.  Firstly, if mankind were so incredibly
warlike, then we'd probably all be dead by now.  We've had nuclear weapons
for over 40 years and not a SINGLE ONE has EVER been used since the end of
World War II (except in tests).  And after World War II, *all* the wars
have been small-scale, limited to relatively small regions of the planet
that have high poverty levels and low education levels.  Korea, VietNam, El
Salvador, Iran, Iraq, etc.  are all small countries with relatively
uneducated populations (Korea being the exception in modern days, but
perhaps not during the Korean War.  I don't have any data on this).

Secondly, most people have a built-in survival instinct that is linked with
the conscious mind, i.e. they won't do something if they know consciously
that it will kill them, unless they have a legitimate reason (e.g., to save
another life).  They can fight knowing that they will die, but they must
have a conscious, legitimate (to them) reason for doing so.  If you were
the leader of a nation and you had the choice of pushing the button,
knowing that you and most of the rest of your nation would die as a result,
would YOU press the button?  I know I wouldn't.  Nor would any other sane
person.  Call me a wimp if you like, but a human race under oppressive
conditions is better than no human race at all...

Which leaves insane leaders.  Fortunately, the world (more specifically,
the western world) has had experience with such leaders, most notably
Hitler.  The Germans TO THIS DAY are quite upset about what Hitler did.
It'll be a long time before Hitler is forgotten.  The population of most
countries will probably try to avoid putting into power someone like Hitler
again if they can help it.  Yes, it's certainly possible that another
leader like Hitler will rise to power in a relatively powerful,
technologically adept country, but it's not likely any time in the near
future.

The destruction of the environment is another matter.  There ARE people
working on the problem, so it becomes a question of whether or not a
timely solution will come about.  The jury's still out on that, so don't
jump to any conclusions.

>> I think the real question on E.T.'s is why don't they want to be seen.
>>
>Now, why wouldn't a race of extraterrestrials want to be seen by us?
>Let's see if we can analyze that question.
>
>If you are on a camping trip in the wilderness, protected by a flimsy
>nylon backpacking tent, and you discover,just around nightfall, that
>you are directly in the path of a hungry, savage, salivating, snarling
>pack of large, ferocious wolves, you do absolutely everything within
>your power to render your presence, and the visibility of your pro-
>tective shelter, and any possible odors, aromas, or fragrances that
>you might be producing, and any and all possible sources of light
>alien to the environment, and every single, possible sound however
>minute, invisible, and then cringe in fear through the night hoping
>that you will not be discovered, and the wolf pack will pass you by.
>
>That would seem to explain the aliens reluctance to encounter humans.

This assumes that the ETs know the specifics about the human race.  For
that to be true, they must either (a) be within 40 light years, or (b) be a
spacefaring civilization with ships that are within 40 light
years (or have visited our system before we had widespread use of radio).
It's difficult to say which is more likely, but my money's on the
spacefaring civilization, mainly because 40 light years is
pitifully, incredibly small compared to the size of the galaxy.

So we have this spacefaring civilization.  You claim that they're afraid of
us because we're so ferocious, right?  Well...

Item 1 : In any system where mutation and natural selection are the basis
for evolution of a species, competition for resources will inevitably
result.  This competition results in aggressive tendencies, since under
those conditions aggression is a beneficial survival trait.  So if the
spacefaring civilization evolved (which seems to me to be the most likely
case), then they, too, will be aggressive in nature unless they've managed
to breed that aggression out of themselves.  I don't know of any other
method besides mutation and natural selection that would cause the
spontaneous rise of intelligent life ("creation" is out because the use of
a supernatural deity is a catch-all explanation.  It's too easy an answer).

Item 2 : They're a spacefaring civilization.  We're not.  How can we
possibly pose a threat to them under these conditions?  We can't even leave
our own earth-moon system in a manned spacecraft yet!  They could attack at
will from a distance and we wouldn't be able to do anything about it.

Item 3 : If they've studied us the way you imply they must have, then they
would also know that the human race tends to expand its influence whenever
possible.  When we develop manned interplanetary travel, we *will* colonize
the rest of the solar system.  When we develop manned interstellar travel,
we *will* colonize other star systems.  This is simply human nature (the
result of evolution.  The wider you spread your genes, the higher the
likelihood that your genes will survive down through the generations).
Now, if we are such a nasty, dangerous race, and so obviously a threat to
these aliens, then the logical thing for them to do would be to exterminate
us.  This is REAL easy to do.  You just drop a big rock on earth from way
out in space.  In fact, the aliens could do this in such a way that it
looks like an accident of nature.  A small change in the orbit of one of
the larger comets out there in the Oort cloud (so THAT's what comet
Austin is...they missed!  :-) ...  If you say they have something against
exterminating other races, then I refer you to item 1 with the addition
that though they may have bred out their natural aggressive tendencies,
they will NOT have bred out their survival instinct, and clearly this is a
matter of survival, right?...

So now that we've established all that, it's time for a more realistic
analogy...

You still remain you, but the pack of hungry wolves now becomes a nest of
fire ants located next to your house.  You know the nest exists, but the
ants in the nest don't know you exist.  Do you flee in terror, abandoning
your house and everything in it?  Do you hide in your house, hoping the
nasty fire ants won't come along and eat you?  No.  What you'll do is
poison the nest, killing most if not all of the fire ants.  Problem solved.


>                                         Derd Valpar
>                                   aka   Marlen
>                                         AZM@NIHCU


                                Kevin Brown
                                CSCI31F7@UHCL2
                                [e-mail]

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

Date: 16 May 90 20:53:31 GMT
From: swrinde!zaphod.mps.ohio-state.edu!sdd.hp.com!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update - 05/16/90


                     GALILEO MISSION STATUS
                          May 16, 1990

     The spacecraft is about 97 million miles from Earth, giving
a round-trip communications time of 17 minutes 23 seconds.  It is
moving in solar orbit at just over 64,500 mph, and has gone
almost 372 million miles since launch.

     The trajectory-correction maneuver was carried out Friday
and Saturday without any surprises.  Two maneuver portions
totalling 2920 pulses from the lateral thrusters were designed by
the Galileo flight team, transmitted by the Deep Space Network,
and executed by the spacecraft as the flight team monitored the
activities.  The result was a velocity change of about 11 meters
per second (25 mph), bringing the trajectory closer to the
desired conditions for the Earth gravity assist in December.
Four more small maneuvers are scheduled over the next several
months to further refine the trajectory.

     After the maneuver, Galileo returned to its regular cruise
routines, keeping sun-pointed and updating its star maps, testing
and calibrating various sensors, and making scientific
measurements of the interplanetary medium.
       _   _____    _
      | | |  __ \  | |       Ron Baalke           |  [e-mail]
      | | | |__) | | |       Jet Propulsion Lab   |  [e-mail]
   ___| | |  ___/  | |___    M/S 301-355          |
  |_____| |_|      |_____|   Pasadena, CA 91109   |

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

Date: 16 May 90 22:36:00 GMT
From: cs.utexas.edu!samsung!zaphod.mps.ohio-state.edu!rpi!rpitsmts![e-mail]  (Commander Krugannal)
Subject: Terraforming Venus



     I've been meaning to reply to the comment that glass is an
   excellent infrared barrier.  The glass in a stove door is
   used as an example.
      Hmmm, I like the idea, perhaps I'll take out all that insulation
   in my walls and replace it with glass! It'll keep all my heat in
   and I'll have a great view!
      Umm, in a word NO!  Think about it next time, perhaps its
   the space or vacumn between the pieces of glass in your stove
   window that keeps the heat in.  Or better yet, take a look
   at a thermos bottle someday.
      Perhaps you were thinking of UV radiation?

   [e-mail]

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

Date: 16 May 90 22:32:03 GMT
From: swrinde!zaphod.mps.ohio-state.edu!uwm.edu!ogicse!zephyr.ens.tek.com!wrgate!mrloog![e-mail]  (Dan Tilque)
Subject: Re: Terraforming Venus (was: Manned mission to Venus)

[e-mail] (Mark SOKOLOWSKI) writes:
> The only thing I would like to
>add to the discussion here is that it is extremely dangerous to try to
>send comets on this planet (of Love... :-) ), for many of this stuff can
>reach the Earth, and the kinetic energy contained brought in by such a
>meteorite when it crashes at 12 to 100 km per second is sufficient to
>vaporize it hundreds of times (remember what happened in Siberia in 1908,
>was there really some kind of cooling down?). In other words we will
>WARM UP Venus instead of cooling it.

True the energy from the comet will heat the atmosphere a little, but
the dust from the impact should cause global cooling.  However, we will
definitely do in any Venusian dinosaurs (dinosaurs just don't adapt
well to celetial impacts).

The Tunguska event is probably not a good example to use: it did not
impact the Earth and didn't toss up any dust.  However, 10 km sized
comet should definitely hit dirt.

>And beside, I don't see we should
>disfigurate the venusian landscapes with craters. For God's sake,
>ALL the solid objects in our solar system (except Venus and Earth) are
>SURSATURATED with those boring, destructive round circles, so please,
>DON'T DESTROY THE BEAUTIE OF VENUS!!!!!

The main reason Earth's and Venus' landscape aren't dominated by craters is
weathering.  Adding water would increase the rate of weathering on Venus.
The craters will be only temporary.

---
Dan Tilque    --    [e-mail]

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

Date: 17 May 90 00:02:47 GMT
From: amelia!wilbur.nas.nasa.gov![e-mail]  (Eugene N. Miya)
Subject: Measurement in space


Some one asked about this:
|                  CONSUMABLE STATUS AS OF 5/15/90
|
|    P R O P E L L A N T    S T A T U S          P O W E R
|
|             Consumption
|             One Week    Propellant Remaining     Output     Margin
|  Spacecraft  (Gm)                (Kg)            Watts      Watts
|
|  Voyager 1    4              36.5 + 2.0          370         59
|  Voyager 2    4              39.6 + 2.0          374         66
                    ^
I wasn't very concern, but over the weekend, the "background process"
sync'ed, and I don't think anyone answered this.  Doesn't look familiar?
All you computer people without a background in engineering or other
physical science?  Sad.  The problem is the person who typed this in
didn't have a symbol for this on his keyboard, the limitations of ASCII.
It's a tolerance, a plus/or/minus sign.  Too much discrete work?  Not
enough uncertainly, no interval arithmetic, etc.?  Welcome to the real
world. 8)

Also, if you look at some of the NASA HQ postings you will find a person
who consistently types an 'l' and 'ell' for a '1' 'one.'  You might
try reading that line on various screens and see how close your
ones and ell's look.

--e. nobuo miya, NASA Ames Research Center, [e-mail]
  {uunet,mailrus,other gateways}!ames!eugene

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

Date: Wed, 16 May 90 15:47:32 +0200
From: mpirbn![e-mail] (Daniel Fischer)
Subject: What was NOTSNIK ???
Cc: [e-mail]

  In Av'Leak May 7, 1990, p.108 Greg Stanley writes on the PEGASUS launcher:

] 30 years ago, the Navy at China Lake was responding to the Sputnik success
] with just such a concept, the NOTSNIK. The then-Naval Ordnance Test Station
] (now the Naval Weapons Center) developed and tested a satellite-carrying
] rocket that was launched from an aircraft.

Is that true? Did it ever work? Why wasn't this way of launching satellites
followed on? I've heard from German aerospace experts that a thing like
Pegasus wasn't possible until recently because the aerodynamics of the first
part of the flight required modern avionics and computers. But 30 years ago???

+- [e-mail] --- Daniel Fischer --- [e-mail] -+
| Max-Planck-Institut f. Radioastronomie, Auf dem Huegel 69, D-5300 Bonn 1,FRG |
+----- Enjoy the Universe - it's the only one you're likely to experience -----+

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

End of SPACE Digest V11 #413
*******************