Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_2/V11_297.TXT

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Subject: SPACE Digest V11 #297

SPACE Digest                                     Volume 11 : Issue 297

Today's Topics:
          Re: Quick launches ( was: Intelsat
       Re: Drake Equation (was Re: Interstellar travel)
       PegBlimp (was Re: Pegasus launch from Valkyrie  (or ...)
            Radar (was Re: Drake Equation
       Re: Drake Equation (was Re: Interstellar travel)
              Re: [HELP] Insult
           Re: Questions about the Voyagers
            Re: Pegasus launch techniques
              Re: SPACE Digest V11 #284
                 space digest
               Re: voyager images on cd
----------------------------------------------------------------------

Date: 20 Apr 90 17:00:27 GMT
From: convex![e-mail]  (Edward V. Wright)
Subject: Re: Quick launches ( was: Intelsat

[e-mail] (Mark Johnson) writes:

>I have a vague recollection of reading an article on Minuteman I operational
>tests in the 1960's. These were apparently conducted by drawing a missile
>squadron out of a hat, and transporting the crewmen and one of their missiles
>to Vandenburg for an operational test firing.

Operational Readiness Test (ORT) firings of ballistic missiles are still
conducted on a regular basis.  That is one of the reasons the Titan II
was retired -- because the Air Force had only about 50 of them, it couldn't
afford to expend them in ORTs.  By the time they were retired, no Titan II
had been ORT fired in more than 20 years, leading to serious doubts about
their operational readiness.

Note that those Titans that are being converted into space boosters
will undergo extensive refurbishment first.

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

Date: 20 Apr 90 06:22:14 GMT
From: news-server.csri.toronto.edu!qucdn![e-mail]  (Arnold G. Gill)
Subject: Re: Drake Equation (was Re: Interstellar travel)

In article <[e-mail]>, [e-mail] (Forrest
Gehrke,2C-119,7239,ATTBL) says:
>
>Voyager level signals are what I would expect to be listening for
>and those means required to make the search.  I don't know of any
>such search going on.
     There are dedicated SETI telescopes in the northern and southern
hemispheres with million channel analyzers being operated by The Planetary
Society.  I can't remember what size dishes they use, but it is being done, and
all by private funding.
-------
 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
|  Arnold Gill                        |                                     |
|  Queen's University at Kingston     |     If I hadn't wanted it heard,    |
|  BITNET   : gilla@qucdn             |       I wouldn't have said it.      |
|  X-400    : [e-mail]  |                                     |
|  INTERNET : [e-mail]  |                                     |
 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

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

Date: 20 Apr 90 06:10:13 GMT
From: bfmny0![e-mail]  (Tom Neff)
Subject: PegBlimp (was Re: Pegasus launch from Valkyrie  (or ...)

I held off on this for a while because it sounded silly, but as I live with
it it doesn't sound so silly anymore.

What about launching Pegasus from a dirigible?

OK, you don't get as many initial MPH as from a Buff, but the aircraft's
speed is only a tiny fraction of what the rocket itself generates, so does
it matter that much?  (Specifically, could you make up for it in rocket
performance given a dirigible launcher?)

In exchange for slowing down, you get INFINITE time to hang around in the
air and get ready for launch.  And lots of space for a launch rack that's
more freely optimized for its job, instead of fitting into a streamlined
fuselage.

There do exist big LTA designs considered buildable if you had a reason.
The Soviets are supposedly going to start a big heavylifter for cargo
work, according to a recent AvWeek.

Just something to think about.

--
"We must never forget that if the war in Vietnam    \ $   Tom Neff
is lost... the right of free speech will be          X    [e-mail]
extinguished throughout the world." -- RN 10/27/65  $ \   uunet!bfmny0!tneff

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

Date: 21 Apr 90 00:32:20 GMT
From: zephyr.ens.tek.com!wrgate!mrloog![e-mail]  (Dan Tilque)
Subject: Radar (was Re: Drake Equation

[e-mail] (Forrest Gehrke) writes:
>
>Hi Power pulsed microwave radars are the best source today for a
>signal that might be detected at +LY distances.  Unfortunately,
>these do not operate continuously and when they are operating they
>seldom stay on one path for very long.  In any military
>operation it's downright dangerous to do so for more than a few pulses.

You're confusing wartime operation with peacetime operation.  In
peacetime, large military radars are fixed in location just like
civilian radars and operate continuously.  These are basically the ones
that watch borders for violations as well as those used for routine
training missions.  However, since some of these are natural targets
(NATO assumes that all it's radar sites in W. Germany will be lost in
the first few minutes of war) there are backup systems which would
operate like you say.

Now the largest military radars (as I said in an earlier post) are
large phased array systems which watch for ICBMs.  The U.S. has five of
them (or did that last I heard).  Three of these, located in Alaska,
Greenland and England, look for missiles launched from the Soviet
Union.  The other two are located on the U.S. east and west coasts and
look for submarine launches missiles.  These last two use over the
horizon radar (using a troposcatter effect, I think) so much or most of
their emissions probably do not escape to space.

The Soviet Union has even more large phased array radars than the U.S.

In order to detect ICBMs, these radars would have to have ranges of
about 2 or 3 times that of regular radars.  That means that (assuming
similar receiver sensitivity) they would use 16 to 81 times the power
of ordinary radar (which typically run about 2-5 MW).

Source: U.S. Air Force training classes (unclassified) plus thinking
about what they told us (not necessarily an encouraged activity).

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

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

Date: 20 Apr 90 20:09:17 GMT
From: haven!aplcen!stda.jhuapl.edu![e-mail]  (Jim Meritt)
Subject: Re: Drake Equation (was Re: Interstellar travel)

In article <[e-mail]> [e-mail] (Tim Bedding) writes:
}From article <[e-mail]>, by [e-mail] (Forrest Gehrke,2C-119,7239,ATTBL):
}> I don't expect any
}> intelligence in this galaxy to initiate a supernova and then
}> sentiently modulate it to get our radio astronomers' attention.
}>
}No, but if a supernova went off by chance, it would make sense to start
}sending signals in the _opposite_ direction.  Any ETs who studied the SN
}closely might notice the signal (or may be smart enough to look for it).
}
}I vaguely remember someone suggesting this neat idea when SN1987a went
}off.  As far as I know, nobody has tried looking for radio signals in
}the direction of it.

Opposite direction relative to what?

Why use radio waves?  You have a very powerful emitter centrally located
already.  Why not just dump a mass into the central star of something
that clearly does not belong there?  A line for technium in the
spectroscopic examination of a star should be a REAL indicator of
a technological civilization nearby.

Any ideas on how much of what could be used?


"In these matters the only certainty is that nothing is certain"
                    - Pliny the Elder
These were the opinions of :
[e-mail]  - or - [e-mail]  - or - meritt%aplvm.BITNET

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

Date: 20 Apr 90 06:18:56 GMT
From: agate!shelby!helens!hanauma![e-mail]  (Joe Dellinger)
Subject: Re: [HELP] Insult

It's worse than you think. Texas passed all these "education reforms",
that required that teachers and students be TESTED to see if they were
learning the material. The tests were put together by committees "drawn
from the finest teachers in Texas". Good idea, right? American education
is in really bad shape, and these sorts of things will help, right?

My sister was an Earth Science teacher in Texas. She obtained for me a copy
of the Earth Science test that was given to HER students to see how well
they knew Earth Science.

Some of the questions:

What planet has an atmosphere similar to Earth's?
1)Jupiter
2)Venus
3)Mercury
4)Mars

correct answer: "Venus"

The nearest galaxy to our own Milky Way Galaxy is located in Andromeda.
What is it called?
1) Large Magellanic Cloud
2) Proxima Centauri
3) Andromeda Galaxy
4) Great Spiral

correct answer: "Great Spiral"
(The author of the question thought "Great Spiral" was the unique proper
name, like "Milky Way". He also somehow got the idea that M31 was the
closest galaxy, even though the LMC is a lot closer.)

The nearest star to Earth besides our Sun is Proxima Centauri. How far
away is it?
1) 8.978372     Parsecs
2) 4.333333     Light Years
3) 3782.483923  Billion Miles

correct answer: 4.333333 Light Years
(Wow, I didn't know they had measured the distance so accurately!)

At what slope of the land can gullying not be contained?
1) 5 ft per 100 ft
2) 6 ft per 100 ft
3) 7 ft per 100 ft
4) 8 ft per 100 ft

correct answer: 6 ft per 100 ft
(Wow, I didn't realize it had nothing to do with soil type, climate, etc.
I guess I'd better climb half dome again before its all covered with gullies.)

Meteorologists model continents as what geometric shape?
1) Triangles
2) Squares
3) Trapezoids

correct answer: triangles
(I'm not kidding.)

Etc. About 1/4 of the questions were OK. About 1/2 of them could be
answered correctly if you had read ONLY the required textbooks. (Much
of the information in those textbooks was years out of date, or "fuzzy"
information was presented as being "hard". As a result, if you knew MORE
than what was in the textbooks, the questions became impossible to answer
"correctly"!) Stanford Earth Science professors I gave the test to _failed_!

I sent back a critique of the test to the committee that made it; I went
point by point and explained as politely as I was able WHY, for example,
it was WRONG to list Proxima Centauri's distance as 4.333333 Light Years,
just because the textbook they drew the question said it was "4 1/3 light
years away".

They wrote back, and said that they had a general policy of not accepting
input from non high-school Earth Science teachers. Since I obviously spent
so much time making my critique, they'd make a special exception for it,
but really they thought the test must have been good since the FINEST
high school Earth Science teachers in Texas had spent THOUSANDS of man hours
writing it!

So if a computer programmer can't even name the planets, it isn't necessarily
his fault. And if he can't even name the planets, what's the big deal about
some stupid robot having snapped a few pictures of Neptune? Without any
background to appreciate Voyager with, how COULD he care? (Do you care about
what values of C13 cause qSV waves in transversely isotropic media to
triplicate?!)
\    /\    /\    /\/\/\/\/\/\/\.-.-.-.-.......___________
 \  /  \  /  \  /Dept of Geophysics, Stanford University \/\/\.-.-....___
  \/    \/    \/Joe Dellinger [e-mail]  apple!hanauma!joe\/\.-._
************** Drive Friendly, Y'all! ******************************************

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

Date: 18 Apr 90 22:34:20 GMT
From: unmvax!nmtsun![e-mail]  (Daniel Briggs)
Subject: Re: Questions about the Voyagers

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>Not a lot can be expected unless something unusual happens, notably having
>one of the Voyagers pass out of the Sun's atmosphere and into the interstellar
>wind.  (There is some hope that this might happen before the Voyagers die,
>but the location of the transition is very poorly known.)  Even so, things
>like plasma particle counts are exciting only to specialists.

Oh come on Henry!  This isn't some dry event to be measured only in
particle counts.  I'm not really a specialist in that field but I find
the notion of the Voyagers reaching the heliopause to be TREMENDOUSLY
EXCITING!!  The heliopause is the transition between the solar wind
and the interstellar medium (which is what I think you meant to say).
We have some reason to expect that it may well be a fairly sharp
transition.  Put it into simple terms.  This is THE EDGE OF THE SOLAR
SYSTEM!  How can you get any more fundamental than that?  If the
spacecraft lives that long we will be able to say (for instance) "On
March 12, 1997 the Voyager II spacecraft passed the median point of
the heliopause and became the first man made object to leave the solar
system."  I'd trade an asteroid encounter (but maybe not a Jovian one)
for that anyday.  This will be the first time we will have sent an
object "OUT THERE".

(To say nothing about the science data, which will be pretty
interesting, too  ;-)

-----
This is a shared guest account, please send replies to
[e-mail] (Internet)
Dan Briggs / NRAO / P.O. Box O / Socorro, NM / 87801  (U.S. Snail)

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

Date: 20 Apr 90 16:25:36 GMT
From: usc!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Pegasus launch techniques

In article <[e-mail]> [e-mail] (Alan Duester) writes:
>However, those things carry a lot of typically overweight people, so it
>might be able to move fast and high, 'specially if you're not worried
>about fuel economies like the airlines supposedly are.

Even figuring people at 200 lbs, a 40klb Pegasus is equivalent to 200+
people, the "+" being because Pegasus adds drag as well as mass.  I don't
think performance is going to be spectacularly better than normal airliner
levels.
--
With features like this,      |     Henry Spencer at U of Toronto Zoology
who needs bugs?               | uunet!attcan!utzoo!henry [e-mail]

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

Date:         Fri, 20 Apr 90 19:36:25 EDT
From: [e-mail]
Subject:      Re: SPACE Digest V11 #284

In response to the question whether or not there is a new orbiter in the Soviet
space fleet, the answer is yes.  I have actually seen pictures of the vehicles
which showed it at that point to be almost completed.  To the best of my know-
ledge this shuttle will be manned (in contrast to Buran 1 which was unmanned).
However, the article which I read also pointed out that this may be the last
shuttle that the Soviets will build.  The name of the new one was given as Bu-
ran 2, even though that may just be lack of information.  I'll look up more
information.

                                                  Uwe

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

Date:         Fri, 20 Apr 90 14:23:00 +0300
From: Alexander Nezlin <[e-mail]>
Subject:      space digest
X-Acknowledge-To: <CONEZLIN@WEIZMANN>


   Hello,

       please remove me from the list of subscribers to the SPACE digest,
or advise me how to do that.

                        Thanks in advance,

                                      Alex Nezlin.

                        e-mail : CONEZLIN @ WEIZMANN.BITNET

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

Date: 20 Apr 90 13:35:20 GMT
From: usc!samsung!umich!terminator!UM.CC.UMich.EDU![e-mail]  (Gavin Eadie)
Subject: Re: voyager images on cd

In article <[e-mail]> [e-mail] (Richard
Ottolini) writes:
> >In fact the Neptune images are not yet released. Jupiter, Saturn and
> >Uranus are available from NSSDC on CD-ROM.
>
> Miya from Ames said last summer that he thought JPL/policy was one year
> delay from acquisition in order to give the principal investigators who
> did the work first crack at the data.

Correct! I'd expect to get the Neptune CD's toward the end of the calendar
year by my guestimate. It is interesting that the CDs were released in the
order Uranus, Saturn then Jupiter. I guess the technology became real
after Uranus and then they worked back through the datasets. It is a lot
of work to get this material together, properly cataloged and then set up
for CD pressing and I'm impressed at the speed of the turnround.

Gavin

U of Michigan Information Services
535 West William Street, Ann Arbor, MI 48103
[phone]

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

End of SPACE Digest V11 #297
*******************