Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V15_0/V15NO044.ZIP/V15NO044

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Date: Tue, 28 Jul 92 05:04:44
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #044
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Space Digest                Tue, 28 Jul 92       Volume 15 : Issue 044

Today's Topics:
                Antimatter (was propulsion questions)
                         Calendar and Zodiak
                       ET's amd Radio (2 msgs)
                            Space position
                     Stellar Structure References
                        Whales (SETI) (2 msgs)
                         Whales and Dolphins

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Date: Mon, 27 Jul 1992 23:53:33 GMT
From: "Thomas J. Nugent" <[e-mail]>
Subject: Antimatter (was propulsion questions)
Newsgroups: sci.space

[e-mail] (James Davis Nicoll) writes:

>In article <[e-mail]> [e-mail] (Michael Ellis) writes:
>>
>>I wouldn't want to be too terribly near to a Shuttle launch either. Or a
>>smoking gas station attendant for that matter.
>>
>>No one is talking about dropping an anti-iron connonball onto a city.
>>Nor would all this antimatter and matter be combined all at once.
>>Payloads of men and equipment can only take so many G's. However, I
>>suppose a launchpad explosion would be a particularly nasty thing.
>>
>>Can anyone say whether an antimatter fueled launch vehicle accident would
>>be worse, the same, or perhaps less (no need to lift all that
>>heavy fuel) than a conventionally fueled rocket?

>    Given that one can mix the antimatter-reaction mass ratio to get
>the Vexhaust one wants, the dangers of standing in the vicinity of the
>exhaust of an antimatter powered ship could be *identical* to that of
>standing inthe vicinity of a conventional ship.

I don't know what type of antimatter powered launch vehicle you are
talking about, but one idea I'd heard was to have a barrel-sized chunk
of tungsten.  Annihilate anitprotons in the middle of it (near the middle,
I should say).  All the radiation produced heats the tungsten (at least
I think it was tungsten) quite nicely, but barely any radiation reaches
the surface.  You pass propellant over the surface of the tungsten, and
voila!  expanding mass, to push your craft along.  The proposal I saw
envisioned this as being alot like an airplane.

"Wishing for something does not make it so."
            - Capt. Jean-Luc Picard
--
"To be average scares the hell out of me." -- Anonymous
Tom Nugent        e-mail: [e-mail]

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

Date: Tue, 28 Jul 1992 04:33:46 GMT
From: Richard Ottolini <[e-mail]>
Subject: Calendar and Zodiak
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (George Hastings) writes:
>To make up the VERY small difference due to precession, as well
>as to adjust for the slowing of the Earth's rotation due to
>tidal drag of the oceans (caused by the moon's gravitation),
>from time to time they declare "leap-seconds" there was one
>this year.
>--


Incorrect.  Precession advances the year appoximately 20 minutes per year.
(24*60*365.2422)/26000.  There are other influences- quakes, solar activity,
weather- that may cause the length of the year to vary one or two seconds
per year.  Since we can measure the length of year to an accuracy of about
a microsecond (one part in 10E14), a second is a noticable effect.
Universal time based is based on atomic vibrations and independent of
astronomical irregularity.

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

Date: 28 Jul 92 06:16:01 GMT
From: ryan korniloff <[e-mail]>
Subject: ET's amd Radio
Newsgroups: sci.space

My only arument is simply this. In the typical galaxy there are 10's of
BILLIONS of stars and there is something like a billion trillion galaxies
in the observable universe. Don't you think that aout of all of thoes
possible combinations that there would be AT LEAST ONE other life form
with higher intellegence? I personally think that there are other
intellegent beings on our Milky Way galaxy alone. I think that 100+
billion combinations is sufficient to allow enough chance that there woul
be other intellegent beings in our galaxy.


          -- Ryan Kornloff
          -- [e-mail]

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

Date: Tue, 28 Jul 1992 07:11:48 GMT
From: Ken Arromdee <[e-mail]>
Subject: ET's amd Radio
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (ryan korniloff) writes:
>My only arument is simply this. In the typical galaxy there are 10's of
>BILLIONS of stars and there is something like a billion trillion galaxies
>in the observable universe. Don't you think that aout of all of thoes
>possible combinations that there would be AT LEAST ONE other life form
>with higher intellegence?

No.  At least not from your argument.

Your argument is basically "Sure, the odds of getting life might be one/a very
large number, but we also have a very large number of stars and galaxies, so
there's got to be life out there".  Your argument gives no reason to belive
that these large numbers are anywhere close in size, and seems instead to
appeal to an (erroneous) intuition that tends to think large numbers are a lot
like other large numbers....
--
Hi! Ani mutacia shel virus .signature. Ha`atek oti letoch .signature shelcha!

Ken Arromdee (UUCP: ....!jhunix!arromdee; BITNET: arromdee@jhuvm;
     INTERNET: [e-mail])

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

Date: 28 Jul 92 02:34:35 GMT
From: John Roberts <[e-mail]>
Subject: Space position
Newsgroups: sci.space

-From: [e-mail] (Allen W. Sherzer)
-Subject: Re: Space position
-Date: 27 Jul 92 12:25:25 GMT

->As opposed to the current thriving SEI program? :-)

-There is a BIG difference between an administration pushing the program
-and looking for ways to fund it and one willing to let it die a quiet
-death.

Good point. Expressing general support for SEI is good, but it has to be
followed up by actual support after the election.

->(It's my own opinion that starting actual manned Mars exploration / lunar
->colonization right now, with current hardware, would be a mistake...

-Why? IMHO most of what we will need we won't develop until we get there.
-The Russians have the best EVA gloves available. They have them because
-they needeed them.

I was referring to the "$400 billion" proposal. The price *has* to come down
before an actual manned flight is attempted. My general feeling is that
at $50-100 billion, it would start to look realistic. Something like Great
Exploration might do it.

->Personally, I hope space is a nonissue in the upcoming election. With such
->a close similarity of platform positions, that might turn out to be the case.

-I doubt space will be an issue. But that isn't a good thing.

I suspect a major portion of the campaign will be on what can be sacrificed
to help balance the budget. Since I consider the space program to be pretty
heavily cut back already, I hope the discussion will be elsewhere. :-)

John Roberts
[e-mail]

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

Date: 27 Jul 92 23:55:18 GMT
From: Graham Flower <[e-mail]>
Subject: Stellar Structure References
Newsgroups: sci.space

      Can somebody recommend a popular or more demanding book that discusses
      the (Bethe) sequence of nuclear reactions that explains the evolution
      of Stars and the distribution of chemical abundances in the universe.

      I would like to work on this at the level of Clayton's book but would
      like to read some popular accounts first so that I have some perspective
      before grinding through the trenches. I would be most appreciative.


Graham Flower ms 90-TT               |  Better to have convictions and act on
Hewlett-Packard  350 W Trimble Rd    |  them, even if they are wrong, than to
Microwave Semiconductor Division     |  waffle in indecision.
San Jose, California, 95131          |
 [e-mail]             |

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

Date: 28 Jul 92 03:55:00 GMT
From: John Roberts <[e-mail]>
Subject: Whales (SETI)
Newsgroups: sci.space

-From: [e-mail] (russell wallace)
-Subject: Re: Whales (SETI)
-Date: 26 Jul 92 23:19:22 GMT
-Organization: Trinity College, Dublin

-By that argument, you could suggest that chairs are intelligent, but for
-reasons we do not understand choose not to reveal that intelligence, and
-instead let humans sit on them and push them around. I would suggest
-that there is absolutely no reason to believe whales are intelligent,
-and that furthermore they definitely do not do certain things that can
-reasonably be regarded as showing intelligence, such as using it to
-preserve their lives (when humans evolved intelligence, this was the
-*first* thing we use it for), and that therefore it is reasonable to
-conclude that whales are not intelligent, unless and until we find some
-evidence that they are.

(Everybody uses chairs as an example - I know folding lawn chairs are
sometimes considered to be diabolically clever, but isn't that carrying
it a little far? ;-)

By this line of reasoning, people who score high on IQ tests but refuse to
wear seat belts are not intelligent, as are those who fear airplanes and
thus choose less statistically safe modes of travel. Similarly, passing on
one's genetic heritage is an aspect of survival, so more intelligent people
must in general be more successful at breeding than less intelligent people,
and insects are more intelligent than either.

By a slight extension, the ability to acquire wealth must be a measure of
intelligence, so professional basketball players are more intelligent than
mathematicians, and people born in India couldn't be too bright, otherwise
it would be a wealthy nation. :-)  :-)

While I agree there's plenty of indication that there are a lot of stupid
whales out there, I'm concerned about the extremely binary nature of your
reasoning - 1=intelligent, 0=non-intelligent, and either all whales are
intelligent or no whales are intelligent.

You also neglect environmental, physiological, and cultural considerations.
Human intelligence is *much* more closely bound to human biology than most
people think. And much of what we consider intelligent behavior is the result
of thousands of years of evolution of our culture. If whales have brains
that are individually capable, but their culture has less ability to evolve
(for instance, they don't appear able to read and write), then that could
account for some of the seeming lack of intelligence.

There have been countless papers written on the subject of what defines
intelligence. I'm not sure the question has ever been satisfactorily
answered. Animal intelligence is even more confusing - remember that even
a mouse brain is more complex in many ways than the biggest artificial
computer ever built.

-(You make suggestions about aliens judging humans by a few religious
-fanatics. It isn't just a few whales that have been killed by whaling
-ships, it's thousands of whales, of many different species, in areas
-separated by thousands of miles.)

If it's numbers you want to go by, remember that the number of human religious
fanatics has always been much greater than the number of whales killed by
humans. :-)

John Roberts
[e-mail]

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

Date: 28 Jul 92 04:12:05 GMT
From: John Roberts <[e-mail]>
Subject: Whales (SETI)
Newsgroups: sci.space

-From: [e-mail] (russell wallace)
-Subject: Re: Whales (SETI)
-Date: 26 Jul 92 23:25:20 GMT
-Organization: Trinity College, Dublin

-In <[e-mail]> [e-mail] (John Roberts) writes:
->Again, one shouldn't expect all whales to have the same level of intelligence.
->It has been reported that there was once a group of killer whales that
->cooperated with a family of Australian whalers over the course of several
->generations. They would help to round up the big whales to be killed, then
->eat the leftovers. Rival whalers encroaching in the territory were driven off
->by the killer whales.

-A better explanation might be that the whalers trained the killer whales
-to do this, in the same way that humans can train dogs to help them hunt
-on land. Killer whales can certainly be trained to do the sort of things
-that dogs can be trained to do.

Wouldn't "self-training" and ability to initiate new behaviors be some
indication of one aspect of what we call intelligence? One of the
household cats around here has shown abilities that you hesitate to
attribute to whales. This cat, in spite of being widely acclaimed as more
stupid than the average cat, regularly teaches itself new tricks, and
when thwarted in some objective, will methodically try numerous alternate
solutions. It's even learned how to open doors by twisting the doorknobs.

If a mere cat (and one of less than average intelligence at that) can do all
this, surely a killer whale can initiate much more complex behavior patterns.

John Roberts
[e-mail]

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

Date: 28 Jul 92 02:13:31 GMT
From: John Roberts <[e-mail]>
Subject: Whales and Dolphins
Newsgroups: sci.space

-From: [e-mail]
-Subject: RE: Whales and Dolphins
-Date: 27 Jul 92 12:16:07 GMT

-> Whales clearly lack some of the intellectual capabilities of humans
-(for
-> instance, humans don't appear to be prone to mass beachings). It
-would be

-But to be fair, this may be due to disease or to perceptual problems
-with their echo-system in shallow waters. It might be a whalish
-equivalent of being stuck in a room with built in optical illusions.

One theory I've heard for a "typical" mass beaching is that one whale
in a pod (usually a young, inexperienced one) gets confused by the
echoes in shallow water and runs aground. Its cries of distress upset
the other whales so much that they fling themselves on the shore, either
in a vain rescue attempt, or as deliberate suicide. I think it's current
practice when one whale is beached and others are seen in the area, if
the whale can't be returned to the water quickly, they shoot it before it
can call the other whales in. (This was covered in the discussion several
years ago.)

One could perhaps view this as emotion dominating over intellect, or as a
case of whales having values different from (most) humans.

John Roberts
[e-mail]

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

Date: 
P
From: John Roberts <[e-mail]>

Newsgroups: sci.space
Subject: Re: Star Trek Realism
Message-Id: <[e-mail]>
Date: 28 Jul 92 02:00:02 GMT
Sender: [e-mail]
Organization: National Institute of Standards and Technology
    formerly National Bureau of Standards
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-From: [e-mail] (tom)
-Subject: Star Trek Realism
-Date: 27 Jul 92 16:47:03 GMT

-As long as we're on the Star-Trek vs. reality thread, here's a question
-that used to come up before my housemate Doug said "Shut up and just watch
-the show!":   When the ship is streaming through space, stars moving past
-at several per second, how is it that the ship is steadily lit from one
-side?  What is the source for this light?  It's pretty bad when you aren't
-even into the actual show, and it's already violating known principles :-)

--Tommy Mac                     .  "  Malcolm X:      +

Hi Tom, glad to have you back!

See the Lensman series, re: ultrawave viewers. :-)

In actual practice, it's fairly complex. The ship is filmed in one pass,
and the cabin lights in another pass. The cameras are computer driven,
so they reproduce the same motion for the second pass. There may be a third
pass to produce the silhouette image to chop out of the background.

The entire show is created on actual movie film (not videotape), so each episode
is roughly equivalent to making a half-length theater movie.

John Roberts
[e-mail]

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

End of Space Digest Volume 15 : Issue 044
------------------------------