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Subject: SPACE Digest V11 #270

SPACE Digest                                     Volume 11 : Issue 270

Today's Topics:
              Re: National Space Society
               Re: Interstellar travel
          Re: Pegasus launch from Valkyrie  (or ...
              Watts per Pound in Space?
                Re: HST Images
            Israeli Space Program
              Re: Fermi Paradox
            Teenage Mutant Ninja Tomatoes
           Re: The effects of decompression
              Re: Israeli Space Program
            B-58 and the Pegasus?
----------------------------------------------------------------------

Date: 13 Apr 90 21:50:34 GMT
From: fernwood!portal!cup.portal.com![e-mail]  (H Keith Henson)
Subject: Re: National Space Society

In response to a sarcastic posting of mine about a NSS survey/membership
recrutement [e-mail] commented about a somewhat more intelegent
survey whch was sent to the members.  I kind of suspect that one was only
mailed to a random sample of the NSS members because I don't remember
seeing it (and I do at least look at what they send to me--a life
member.)  If they were really interested in what the NSS members think,
a relatively small and inexpensive sample would tell them.
Keith Henson

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

Date: 13 Apr 90 22:51:02 GMT
From: fernwood!portal!cup.portal.com![e-mail]  (H Keith Henson)
Subject: Re: Interstellar travel

[e-mail] (Jeffrey Kirk Bennett) made a bunch of points about
this topic.

1)  The goal ----

The goal is to have a good time, and keep from getting bored.
(Seriously!)

2)  (Technical problems about interstellar flight)

There are many ways to get there, my personal is to tap significant
fractions of the (now wasted) energy of stars and go by laser light
sail.  But any method which gets you up to .5 c or better will do,
all it take is patience.

3&4) Local fuel/power, and no problem to find your way back, Earth is
a beacon of radio waves.

And, we don't have the technology, or the wealth, but (assuming things
hold together) I think there is a strong case we will.  (Nanotechnology)

On ET's, life may be common, but I suspect we are the only technophylic
life "in sight".  On UFOs, at least some of them are pranks, I personally
have been responsible for perhaps a hundred sighting when I was younger.

Keith Henson

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

Date: 12 Apr 90 16:20:05 GMT
From: cs.utexas.edu!news-server.csri.toronto.edu!torsqnt!lethe!tvcent!comspec!censor!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Pegasus launch from Valkyrie  (or ...

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>>... what current planes could carry 40,000 lbs at such speeds;
>
>I was wondering if a FB-111 would do? My copy of Janes says it will carry a
>bomb load of 37,500 which is pretty close...

With such loads it is almost certainly subsonic, giving no advantage over
the B-52.  The F-111 family is generally overweight and underpowered, and
is "supersonic" only by courtesy. :-)  It's vanishingly unlikely that any
of them could reach, say, Mach 2 with a heavy external load.

A B-58 might be able to do it, if there were any of them left.  It was
*designed* to carry a heavy external load supersonic, since it had no
bomb bay -- its bomb was built into its huge drop tank.  There may still
be some left in storage at Davis-Monthan or related places, but it would
probably be difficult and expensive to refurbish one, even assuming the
USAF would sell you one.
--
With features like this,      |     Henry Spencer at U of Toronto Zoology
who needs bugs?               | uunet!attcan!utzoo!henry [e-mail]

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

Date: 14 Apr 90 04:11:54 GMT
From: att!cbnews![e-mail]  (polivka al 60047)
Subject: Watts per Pound in Space?



From: [e-mail] (polivka al 60047)
[mod.note:  Followups to sci.space. - Bill ]

Does anyone out there have any good rules of thumb as to how many
watts per pound you can get out of a spacecraft power source?

Specifically interested in:
 - solar (not nuclear) source,
 - with battery for 24 hour operation,
 - generation of raw 100 volt power bus only (not regulated power).

Basically, what is d(Watt)/d(Pound) in the general region of around 1 kW
total power output (i.e. "delta Watts" per "delta Pound").

I need to know the weight to generate the typical raw "bus" power
(e.g. at 100 volts), not regulated power.  Thus, I'm interested in
weight of things like solar panels vs. how many watts they generate,
battery, weight of circuitry associated with providing a 100v bus.
Not interested in DC-to-DC converter weight.  Just looking for a
bottom line X watts/lb rule-of-thumb.

Thanks,
Al

--

------------------------------------------------------------------------
Al Polivka                           arpa: [e-mail]
Mail Stop 102-4858                 usenet: uunet!x102a!apolivka
Harris Corporation                  phone: [phone]
Government Aerospace Systems Div.    Bldg: 102 Room: 3433
P.O. Box 94000
Melbourne, FL 32902
------------------------------------------------------------------------

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

Date: 16 Apr 90 00:19:46 GMT
From: snorkelwacker!usc!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: HST Images

In article <5A040F0F19280354-MTABWIDENER*DXANDY@widener> [e-mail] writes:
>  What's to stop some enterprising amateur (or professional) astronomer
>from intercepting the signals from the HST and decoding them himself?  Would
>this be a particuarly difficult operation?  If it is possible, what be the
>legal situation?

Between microwave transmission frequencies and esoteric modulation and
digital coding schemes, it would not be trivial but probably could be
done by a determined and resourceful amateur.  Actually you'd intercept
the downlink from the TDRS, since HST's own antennas are pointed at
the TDRS rather than at Earth.

The legal side of this varies from country to country, and has changed
some in the US of late, but the old standard rule for radio transmissions
not meant for general broadcast is that listening is legal but passing the
resulting information on to others is seriously illegal.
--
With features like this,      |     Henry Spencer at U of Toronto Zoology
who needs bugs?               | uunet!attcan!utzoo!henry [e-mail]

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

Date: 16 Apr 90 04:09:42 GMT
From: pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!dsinc!netnews.upenn.edu!cps3xx!cpsvax![e-mail]  (Ytshak Artzi - CPS)
Subject: Israeli Space Program


  Does anybody have any information on the Israeli space ventures ?
I just now that they successfully put a satelite in low orbit last year
( for several days I think). I also read in the Jerusalem Post that a
more sophisticated one is planned this year (summer?), using the Israeli
developed Shavit rocket. The satelite is supposed to supply info on
military operations in the neighbouring Arab countries.

  Thanks.

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

Date: 16 Apr 90 05:51:28 GMT
From: cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Fermi Paradox

In article <[e-mail]> [e-mail] (David Jay Rostker) writes:
>    Am I confused? I thought that Fermi's Paradox stated that we would
>never find an advanced technology. The reasoning was that any
>technologically advanced civilization capable of space travel or at
>least capable of communication with us would have destroyed itself by
>now.

No.  This has been advanced as an explanation for the Fermi Paradox
(perhaps by Fermi himself, given that he was a prominent participant in
the Manhattan Project), but the paradox is lack of contact in a galaxy
that ought to be full of advanced civilizations.

Self-destruction has never looked (to me) like something that could account
for *all* advanced civilizations going belly-up.  It's difficult to totally
destroy a civilization once it has gotten into space in a serious way.  We
haven't done that yet, but we clearly might have it underway by now if
everything had gone right.  Even now, the probability of self-destruction
here has been declining over the last couple of decades; there's still
a good chance that we will make it out of the womb before we self-destruct.
--
With features like this,      |     Henry Spencer at U of Toronto Zoology
who needs bugs?               | uunet!attcan!utzoo!henry [e-mail]

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

Date: 16 Apr 90 18:04:56 GMT
From: zaphod.mps.ohio-state.edu!sdd.hp.com!elroy.jpl.nasa.gov!aristotle![e-mail]  (Peter Scott)
Subject: Teenage Mutant Ninja Tomatoes

How about that announcement from NASA backpedalling on the possibility
of the tomato seeds having mutated into toxic forms from the extra
cosmic radiation they underwent?  The news station I was watching showed
clips from "Attack of the Killer Tomatoes" while running this item.

What about it, biologists?  Right now, 12 million tomato seeds from
space are en route to innocent children around the country.  Should we
ship them all into the Sun before our nation's youth is consumed by
flesh-eating, shape-changing fruit?

Don't laugh.  There could be a space tomato growing in a classroom
near you right now.

:-)  :-)  :-)

But anyway, what kinds of mutations might we expect, given the
especially energetic particles these seeds had to deal with?

This is news.  This is your       |    Peter Scott, NASA/JPL/Caltech
brain on news.  Any questions?    |    ([e-mail])

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

Date: 17 Apr 90 02:40:40 GMT
From: cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: The effects of decompression

In article <[e-mail]> [e-mail] (Mark SOKOLOWSKI) writes:
>I am wondering wheter or not a human body exposed to void would explode,

Sigh, another one for our nonexistent frequently-asked-questions list...
From an earlier posting of mine on the subject:

Rapid decompression to low-grade vacuum has been tried (on animals).
Nobody's tried whole-body exposure to vacuum on humans, that I know of,
but exposing parts of the body (e.g. hands) has been done a fair bit.
Contrary to popular mythology, none of these awful things happen.  The
animals exhibit some distress (understandable!) and after some seconds lose
consciousness.  After repressurization they recover and show no serious
aftereffects.  Parts of the human body in vacuum will swell somewhat
after a minute or so, but no particular pain is involved, there is no
explosion, and the effects seem to be fully reversible on recompression.

Loss of air from the lungs is inevitable, but the rate would normally be
limited by other factors (e.g. how big the hole in the wall was), and the
only significant hazard would be rupturing your eardrums if you had a cold
or otherwise didn't get your ears depressurized properly.  There is some
cooling effect from evaporation of sweat, much as there is in air, but
vacuum has no temperature and there is no reason why you would "rapidly
freeze".  And your skin is a good grade of leather, and does a good job
(temporarily!) of holding in your body water.

After ten minutes it would undoubtedly be different, but the only problem
with a brief exposure to vacuum is inability to breathe.
--
With features like this,      |     Henry Spencer at U of Toronto Zoology
who needs bugs?               | uunet!attcan!utzoo!henry [e-mail]

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

Date: 16 Apr 90 14:44:51 GMT
From: shlump.nac.dec.com!quik07.enet.dec.com![e-mail]  (Ben Burch)
Subject: Re: Israeli Space Program

In article <[e-mail]>, [e-mail] (Ytshak Artzi -
CPS) writes:
>                          ... I also read in the Jerusalem Post that a
> more sophisticated one is planned this year (summer?), using the Israeli
> developed Shavit rocket. The satelite is supposed to supply info on
> military operations in the neighbouring Arab countries.

They demand-launched a satellite a week or so ago in response to some
Iraqi saber-rattling.  I was a bit amazed that they were able to do
this.  Either they have the kind of "Go and do it" attitude that NASA
once had, or they were almost ready to launch in the first place.

Maybe a bit of both.

- Ben Burch   ([e-mail])

"Views expressed herein are not those of Digital Equipment Corporation."

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

Date: 15 Apr 90 13:51:20 GMT
From: tiamat!mjbtn!raider![e-mail]  (John Wilson)
Subject: B-58 and the Pegasus?


    I missed the beginning of this thread but since the B-58 is being
mentioned, I can't help but get involved. The information I am adding
is from AEROGRAPH #4 - CONVAIR B-58 by Jay Miller (without permission).

>[e-mail] (Allen W. Sherzer) writes:
>>>... what current planes could carry 40,000 lbs at such speeds;
>>I was wondering if a FB-111 would do? My copy of Janes says it will carry a
>>bomb load of 37,500 which is pretty close...
>
>Henry Spencer at U of Toronto Zoology  writes:
>With such loads it is almost certainly subsonic, giving no advantage over
>the B-52.  The F-111 family is generally overweight and underpowered, and
>is "supersonic" only by courtesy. :-)  It's vanishingly unlikely that any
>of them could reach, say, Mach 2 with a heavy external load.
>A B-58 might be able to do it, if there were any of them left.  It was
>*designed* to carry a heavy external load supersonic, since it had no
>bomb bay -- its bomb was built into its huge drop tank.  There may still
>be some left in storage at Davis-Monthan or related places, but it would
>probably be difficult and expensive to refurbish one, even assuming the
>USAF would sell you one.
>
>[e-mail] (john.a.welsh) writes:
>We have seen here that if you want to launch more with a Pegasus,
>you need more speed in the booster plane.  There is only 1 B70
>left, and I don't think the Airforce Museum in Dayton will let
>anybody use it (who would certify it air worthy, too?).  So how
>about the next fastest bomber, the B58?  Were they all broken
>up or are there other museum pieces around (other then Dayton's)?
>A B58 held the coast to coast record that the SR71 broke (LA - NY
>in about 2 hours) and they were in regular airforce service, so
>they were not experimental oddities.  They had external pods so
>they could carry more than their bomb bays could hold, though I
>am not sure if they could go supersonic with the pods (I think
>they could).  If we are discussing B70s here, why couldn't we have
>a B58 launch Pegasus?
>
>[e-mail] (john.a.welsh) writes:
>>[B-58] They had external pods so
>>they could carry more than their bomb bays could hold, though I
>>am not sure if they could go supersonic with the pods...
>
>Henry Spencer at U of Toronto Zoology replies:
>The B-58 in fact had no bomb bay; *all* the payload was in the pod.  And
>yes, they could go supersonic with the pod in place, although the one
>major constraint on going supersonic was "pod fuel tanks empty", which
>might imply a constraint on how much weight could be in the pod at
>supersonic speed.

    Some B-58 Specs. (from the book):

B-58A basic weight (w/o pod)        57,916 lbs.
      max. taxi weight               147,000 lbs.
      max. gross (in flight)           176,890 lbs.

TCP (two component pod)
    overall length    (together)    54 feet
    max diameter             5 feet
    fuel & Mk.53 bomb weight    37,970 lbs.

The `58 also carried four Mk.43 1-Meg.ton yield thermo-nukes weighing
    ~2100 lbs each.          8,400 lbs. total
                      ( 46,000+ lbs. external payload)
                            plus internal fuel (?)
On August 2, 1961 the first *Mach 2* multi-weapon test drop was made. All
    tactically configured B-58's were retrofitted to this capability.

The B-58 "had been flown at 85,000 ft. with payload" ....
     "...was not power limited" ....
     "...was structually, and air intake temperature limited"...

    From these, and other statements made (in the book), I conclude
    that the `Hustler' was capable of of Mach 2 runs at altitude
    (40,000+ ft.) with payload and that Mach 2 drops were also possible.
    The greatest problem with the `58 as a tactical weapons delivery
    platform was it's limited range.

    Considering the above data, would the B-58 Hustler have made a viable
    Pegasus launch platform? (I missed the Specs. on the Pegasus).

Unfortunately, of 116 Hustlers built, 26 were destroyed, 8 are on static
  display and the remainder were scrapped.

BTW - Anyone know if the B-58 will be covered on The Discovery Channel's
    WINGS program?
--
================================================================================
...the greatest sensation of existence,| J.P.Wilson - Electrocom Automation Inc.
not to trust, but to know.       A.R.  | (remote site) - Atlanta, GA
============  ..raider!ecaga1!jpw     ...gatech!emory!jdyx!ecaga1!jpw  =========

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

End of SPACE Digest V11 #270
*******************