Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V15_3/V15NO384.TXT

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Date: Fri,  6 Nov 92 05:03:40
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #384
To: Space Digest Readers
Precedence: bulk


Space Digest                Fri,  6 Nov 92       Volume 15 : Issue 384

Today's Topics:
    "average" underground nuclear explosion (was : moving comets)
                           Comet Collision
                           Hubble's mirror
                          Light sails again
                        NASA Coverup (6 msgs)
                       Need Specific NASA Image
                           U.N. Moon Treaty
                            X-15  pictures

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

Date: 5 Nov 92 16:44:29 GMT
From: Russ Brown <[e-mail]>
Subject: "average" underground nuclear explosion (was : moving comets)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] ("Phil G. Fraering") writes:
>
>
>>I read once that the average underground nuclear explosion created spaces
>>in rock half a mile across.  (Anyone confirm this?)
>>Andy.
>
>Average underground nuclear explosion? This implies that they're
>naturally occuring or something...
>
>I think it's a lot less than this, otherwise the underground testing
>ranges in Nevada would be running out of rock...
>

The larger ones go about 400 ft high by 1200 deep.  Lots of smaller ones
were done.

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

Date: Thu, 5 Nov 92 15:08:51 GMT
From: Dave Jones <[e-mail]>
Subject: Comet Collision
Newsgroups: sci.space,alt.sci.planetary

Wayne Harvey ([e-mail]) wrote:
>
> >In <[e-mail]> [e-mail] (John Black) writes:
>
> >>Maybe a near comet approach could be a good thing. I did a rough calculation
> >>and estimated that there must be something of the order of 10 to the power 11
> >>metric tonnes of water. Maybe in 130 years time somewhere on the Earth could
> >>do with some water,  <et cetera>
>
> Here's something that people seem to be missing, that has been bandied about
> by SF writers for a long time: 10^11 tonnes of water (and associated other
> shit), if we could capture it and place it in Earth orbit, would provide
> us with an awful lot of fuel for rockets. Perhaps we could even have fusion
> rockets when the comet comes back in 130 years, and that would make for
> some pretty inexpensive colonisation fuels.
>
This one's not a great bet.  For a 50 km/s velocity change, about what it
would take to get the comet into Earth orbit under ideal conditions, you
have a mass ratio of about 1/163 if you assume some fairly optimistic
numbers for rocket efficiency.  In other words, take 1.63 x 10^13 tonnes of
your own reaction mass to the comet (requiring 163 times that to match
velocities) or take your energy source there and use it to throw away
162/163 of the comet as reaction mass.  Actually, the delta V is even
worse because there's Earth's orbital velocity to take into account.
The mass ratio could be 2-4 times worse.

The same technology can put icebergs in orbit for much less cost...

Incidentally, re Asimov's "Martian Way", I estimated Saturn orbit to
Mars orbit as dV= 5.5 km/s, with another 3.5 km/s for landing on Mars.
You could fly a Saturn ring fragment to Mars using about 3/4 of it for
reaction mass (Isp = 1000 or so) but I'm afraid Ike was way off.  He
had about 2% used for reaction mass, along with out-of-plane orbits,
continous boost trajectories, you name it.  Give the guy a break, he
was a biochemist.....he also wasn't to know that ring fragments aren't
big enough for the scheme (his was 1 cu. mile).

> Has anybody read Arthur C. Clarkes' 2051: Oddessey 3?
>
Well, yes.  They visited Comet Halley (that's 2061, BTW).  What else?
Oh, they used Sakharov's Cold Fusion (mu meson catalysis) for energy.
Anything else?

--
||Halloween Candy: the office snack    |
||from Nov. 1st onwards............... |Puff the Magic Dragon
||-------------------------------------|Lived by the sea
||Dave Jones ([e-mail])|Who knows what's in the autumn mists
||Eastman Kodak Co. Rochester, NY      |In the mind of Yadallee?

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

Date: 5 Nov 92 15:55:21 GMT
From: "William H. Jefferys" <[e-mail]>
Subject: Hubble's mirror
Newsgroups: sci.astro,sci.space

In article <[e-mail]> [e-mail] (Donald H. Locker) writes:
#Now that I know a little about mirror-making, I'd like to hear again
#how the Hubble mirror contractor messed up the figure of the main
#mirror.  I understand it has spherical aberration, but wonder how
#[Rockwell?] managed to do that.

The Hartford Courant had a Pulitzer Prize winning
series of reports that go into gory detail on this.
They may still have copies available. It's entitled
"Hubble error: Time, money and millionths of an inch."
Write the Hartford Courant, 285 Broad St., Hartford
CT, or call Corporate Affairs Manager Sylvia Levy
at [phone].

Bill

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

Date: Thu, 5 Nov 1992 15:58:25 GMT
From: Nick Haines <[e-mail]>
Subject: Light sails again
Newsgroups: sci.space

In article <ida.720921989@atomic> ida@atomic (David Goldschmidt) writes:

[about light-sails]

      force            force
    | /               \  /
    |/         or      \/________>  light path
    /_____>            /|
       /|                 / |
      / | <light         /  |
     ^mirror            ^mirror

     If possible could somebody explain why it happens whichever way.  Its not
   clear to me why the energy lost or gained in red or blue shifting the light
   has to go into kinetic energy  (couldn't it just heat up the sail?)

The left-hand diagram violates conservation of momentum. The
right-hand diagram is correct. Net force for a perfectly-reflecting
mirror is perpendicular to the mirror.

Energy lost or gained (and red- or blue-shifting) is irrelevant. Think
always in terms of momentum transfer, then it's easy.

(tried to send this by mail but you don't have a real Internet address
and I can't be bothered to figure out bang-paths).

Nick Haines [e-mail]

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

Date: Thu, 5 Nov 1992 14:57:36 GMT
From: Andrew Poutiatine <[e-mail]>
Subject: NASA Coverup
Newsgroups: sci.physics,sci.space,alt.conspiracy

In article <[e-mail]> [e-mail] writes:
>In article <[e-mail]>, [e-mail] writes...
>>
>>
>>    Well  ,  it  sounds  like the willingness to cling to some kind of la-la
>>   land belief that our  government  wouldn't  lie  to  us  about  the  moon
>>   landings  won't  just  melt  in  the  face of straightforward ,elementary

>>   mathematics ,and piles of circumstantial evidence. I guess I'll just have
>>   to use even bigger piles of circumstantial evidence and MORE  math.  Here
>>   goes:
>
>Well, since if the Moon's gravity were 0.64G rather than around 0.16G, this
>would mean the Moon is 4 times as massive than it allegedly is as we know
>its diameter.  But if this were the case, the Earth-Moon mass ratio would be
>quite different, thus the barycenter would move, tides would be quite
>different, the motion of the Earth-Moon system around the sun would be
>different,  and so forth, none of which correspond to observed information.
>
>

Not if they have lied about the mass of the earth, the sun, the density of
water, and perhaps even the gravitational constant (not to mention where they
were when they said they were going to be working late!) :^)  ;^)  :^) .

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

Date: 5 Nov 92 17:53:07 GMT
From: Mike McCants <[e-mail]>
Subject: NASA Coverup
Newsgroups: sci.space,alt.conspiracy

In article snarfy writes:
>
>In message Dennis comments:
>
>>Also the pertubations of Lunar orbits by the Earth and Sun become
>>significant at altitudes above 800 km and dominate above 22,000.

You should also say that satellites in Earth orbits that go to high
altitudes are very significantly affected by lunar and solar perturbations.

>Where did you read this?  Was this a paper based on theory or the actual
>flight trajectories of real spacecraft?  If it's true, I'll be the first
>to admit that it shoots my theory ...but I'd like to see for myself.
>
>snarfy

The Goddard publication, Satellite Situation Report, gives some of the
orbital parameters for thousands of objects in Earth orbit.  These values
are taken from current NORAD orbital elements.  Needless to say, the
orbital parameters do change in a way that is quite consistent with
the known values of mass, distance, and gravity.

The 1966 object, ATS 1, now has an inclination of 14 degrees.  The
original geosynchronous inclination was 0 degrees.

The Soviet payload, Astron, in a 5 day orbit, was launched in 1983 into
an orbit with an inclination of 51 degrees.  The current inclination is
32 degrees.  A year ago it was 24.  The large changes over the last
19 years are very well explained by proper computations.  It's not very
bright at 20000 miles, but I've seen it and I believe it.

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

Date: 5 Nov 92 18:24:25 GMT
From: "Peter J. Scott" <[e-mail]>
Subject: NASA Coverup
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Ian Matthew Burrell) writes:
> This post will attempt to completely destroy the allegation that the
> government is hiding some undefined fact about the Moon's mass or density.
> For, if what a you say is true, the Moon must have much different mass
> than accepted.
>
> First some numbers:
> Mass of the Earth: 5.98 x 10^24 kg
> Radius of Earth: 6.37 x 10^6 m or 6370 km
> Mass of Moon: 7.34 x 10^22 kg
> Radius of Moon: 1.74 x 10^6 m or 1740 km
> Distance from Moon to Earth: 3.84 x 10^8 m or 384,000 km
>
> Using the equation from Newton's Law of Gravitation, a = (G*M)/R^2, the
> acceleration due to gravity at the Earth's surface is 9.8 m/s^2 (1G) which
> is a undeniable physical fact.

Ah, but have you personally verified Newton's Law of Gravitation?  After
all, who do you think started this whole conspiracy?  Can any of us say
that we really knew Isaac Newton?  Einstein started to cotton on to the
whole thing but by that time the conspirators were too well established
and managed to divert his attention into the bottomless quagmire of quantum
mechanics.

Oh, and you should see the pictures the Mars Observer boys are cooking up
for encounter; marvelous stuff.  The Galileo image fabrication lab had a
little problem getting Renderman working on their Apple II+s, hence the
HGA cover story.  If they get enough pictures ready in time, that "hammering"
maneuver will save the day.  Great idea, almost as good as the VEEGA concept...

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

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

Date: Thu, 5 Nov 92 15:47:26 GMT
From: Dave Jones <[e-mail]>
Subject: NASA Coverup
Newsgroups: sci.space,alt.conspiracy

[e-mail] wrote:
>    In   message-ID:  <[e-mail]>  Dennis,  University  of
>       Alabama in Huntsville comments :
>
>  > Henry can probably provide the numbers.
>
>    Who's Henry?
>
Nothing could more clearly demonstrate Attention Deficit Syndrome.
Try reading something other than your own postings for a while.

--
||Halloween Candy: the office snack    |
||from Nov. 1st onwards............... |Puff the Magic Dragon
||-------------------------------------|Lived by the sea
||Dave Jones ([e-mail])|Who knows what's in the autumn mists
||Eastman Kodak Co. Rochester, NY      |In the mind of Yadallee?

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

Date: 5 Nov 1992 18:48:30 GMT
From: David Gutierrez <[e-mail]>
Subject: NASA COVERUP
Newsgroups: sci.space

I think the mass of the moon HAS changed, due to the HEAVY BOOTS the astronauts
left behind.

BTW, that's also why they couldn't do backflips - their boots were too HEAVY.

(Is that enough CAPS? :-)

David Gutierrez
[e-mail]

"Only fools are positive." - Moe Howard

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

Date: 5 Nov 92 19:58:22 GMT
From: "Michael V. Kent" <[e-mail]>
Subject: NASA Coverup
Newsgroups: sci.space,alt.conspiracy

In article <[e-mail]> [e-mail] (Dave Jones) writes:
>[e-mail] wrote:
>>
>>    Who's Henry?
>>
>Nothing could more clearly demonstrate Attention Deficit Syndrome.
>Try reading something other than your own postings for a while.

Don't be so quick to flame.  This thread is cross-posted to sci.space and
alt.conspiracy.  Although we on sci.space may know Henry on a first name
basis, the rest of the net probably does not.

For those on alt.conspiracy:  Henry is an artificial intelligence (AI) project
at the University of Toronto whose job is to keep the signal to noise ratio
of sci.space from getting too low.  :)

Mike

--
Michael Kent                                   [e-mail]
McDonnell Douglas                              Rensselaer Polytechnic Institute

Tute Screwed Aero Class of '92                              Apple II Forever !!

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

Date: Thu, 5 Nov 1992 19:41:18 GMT
From: Gerry Roston <[e-mail]>
Subject: Need Specific NASA Image
Newsgroups: sci.space

Would some please
 - Send me
 - Send me a pointer to
an online copy of this image: Lunar Orbiter 5, Frame M-191.  The image
format is not particularly important as I'll convert it to what we need.

Thank you.

--
Gerry Roston ([e-mail])    | Because experience witnesseth that eccle-
Field Robotics Center,          | siastical establishments, instead of main-
Carnegie Mellon University      | taining the purity and efficacy of Religion,
Pittsburgh, PA, 15213           | have had a contrary operation.  During almost
[phone]                  | fifteen centuries has the legal establishment
                                | of Christianity been on trial.  What have been
The opinions expressed are mine | its fruits?  More or less in all places, pride
and do not reflect the official | and indolence in the Clergy, ignorance and
position of CMU, FRC, RedZone,  | servility in the laity, in both, superstition,
or any other organization.      | bigotry and persecution.  James Madison

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

Date: Thu, 5 Nov 92 15:23:32 GMT
From: Dave Jones <[e-mail]>
Subject: U.N. Moon Treaty
Newsgroups: sci.space

[e-mail] wrote:
>    There is susposed to be something in international law about any country
> over which the Moon passes directly (plumb) has some kind of claim but I'm
> having a hard time tracking the particulars.
>
That's from Heinlein's "The Man Who Sold The Moon".  If you're having a hard
time finding the particulars its probably because they don't exist, though
you should be able to locate oodles of declarations that the Moon belongs to
all humankind.

--
||Halloween Candy: the office snack    |
||from Nov. 1st onwards............... |Puff the Magic Dragon
||-------------------------------------|Lived by the sea
||Dave Jones ([e-mail])|Who knows what's in the autumn mists
||Eastman Kodak Co. Rochester, NY      |In the mind of Yadallee?

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

Date: 5 Nov 92 09:58:54 EST
From: Chris Jones <[e-mail]>
Subject: X-15  pictures
Newsgroups: sci.space

In article <[e-mail]>, claudio@nmsb (Claudio Egalon) writes:
>I would like to know where I could get hold of X-15 pictures for
>possible publication. I am also interested, specifically, in a picture of
>one of the first flights of the X-15 that was flown by Scott Crossfield in
>which the (space)craft crashed and was broken in its very middle
>(Crossfield survived). I have never seen a picture of the X-15 after this
>accident and I am curious how it looked like.

I don't have any pointers to stills, but the show "The Rocket Pilots" (I think
that's the title), originally aired on NBC and occasionally rerun on A&E, has
film footage of this accident.  It's exaggerating to call it a crash: the
engine caught on fire and was shut down.  There wasn't enough time to dump the
whole fuel load before landing, so the craft was too heavy for the loads it
underwent on landing.  Crossfield did put it down nicely, and the fuselage
broke.  He received a trophy from the Southern California Soaring Society (a
streamlined brick mounted on mahogany) for the shortest time from 38000 feet
to the ground in a glider.

The flight took place on 5 November 1959, and was the fourth flight of the
program, and the third of the number two X-15.
--
Chris Jones    [e-mail]

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

End of Space Digest Volume 15 : Issue 384
------------------------------