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Date: Thu, 5 Nov 92 05:06:24
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V15 #380
To: Space Digest Readers
Precedence: bulk
Space Digest Thu, 5 Nov 92 Volume 15 : Issue 380
Today's Topics:
"Earth Gains a Retinue of Mini-Asteroids" (2 msgs)
Heavy Boots, Again (was: NASA Coverup)
How to electronically detect X-RAYS???
Hubble's mirror (2 msgs)
Media Survey
NASA COVERUP (4 msgs)
Russian Engines for DC-Y?
Vacuum gloves
Welcome to the Space Digest!! Please send your messages to
"space@isu.isunet.edu", and (un)subscription requests of the form
"Subscribe Space <your name>" to one of these addresses: listserv@uga
(BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle
(THENET), or space-REQUEST@isu.isunet.edu (Internet).
----------------------------------------------------------------------
Date: 4 Nov 92 20:28:22 GMT
From: Jim Scotti x2717 <jscotti@lpl.arizona.edu>
Subject: "Earth gains a retinue of mini-asteroids"
Newsgroups: sci.space
In article <Bx1pK6.MEC.1@cs.cmu.edu> REIFF@spacvax.rice.edu ("Patricia Reiff (713")) writes:
>In a recent SD, pgf@srl05.cacs.usl.edu (Phil G. Fraering) writes:
>
>>>These couldn't be Frank's minicomets, could they? His putative
>>>objects are supposedly in prograde, earth-like orbits, to reduce the
>>>impact velocity enough to avoid observational constraints.
>
>>I'd bet Frank will claim that these bodies represent the "larger"
>>members of his mini-comet population, but I don't know.
>
>I can affirm that Lou Frank considers these results to be confirmation of
>the "small-comet" hypothesis, and his calculations show that the fluxes are
>approximately correct.
>
> {Some stuff deleted...}
On the contrary, in his earlier work, Frank made some estimates for
how many small comets are necessary to account for his detection rate.
The rate of impact on the Earth of his cometesimals is about 10 million
per year. The rate of impact of our 10 meter objects is on the order of
about 10 per year. I believe his estimates of size placed his objects
in the 10-30 meter class. He would therefore expect about a million
times as many objects as we are seeing or we should detect on the order
of 30000 of his cometesimals EACH NIGHT! I think we quite effectively
disprove his hypothesis on the existance of cometesimals as he has
proposed them. (Note: My estimate of 30000 per night differs from
my estimate in an earlier post since I made the earlier estimate from
my memory of his work. I looked up his estimate before revising it and
I was apparently over conservative in my memory, having said earlier
that we should detect about 1000 per night.)
I'd like to see his latest estimates for the number and size of his
small comets required to account for his detection rates. He must
have downsized them considerably to account for the 6 order of magnitudes
required to reconcile the difference between his estimates and the
Spacewatch discovery rates.
>------
>From the First Space Science Department in the World:
> : _^ ^_ ____
> Patricia H. Reiff : / O O \ |GO \
> Department of Space Physics and Astronomy : \ V / |OWLS\
> Rice University, Houston, TX 77251-1892 : / ""R"" \__/
> internet: reiff@spacvax.rice.edu (128.42.10.3) \ ""U"" /
> SPAN: RICE::REIFF : _/|\ /|\_
>
>"Why does man want to go to the Moon? ... Why does Rice play Texas?"
> ....JFK, Rice Stadium, 1962
Jim.
---------------------------------------------
Jim Scotti
{jscotti@lpl.arizona.edu}
Lunar & Planetary Laboratory
University of Arizona
Tucson, AZ 85721 USA
---------------------------------------------
------------------------------
Date: 4 Nov 92 20:47:44 GMT
From: Jim Scotti x2717 <jscotti@lpl.arizona.edu>
Subject: "Earth Gains a Retinue of Mini-Asteroids"
Newsgroups: sci.space
In article <Bx3CM5.7Gx.1@cs.cmu.edu> amon@elegabalus.cs.qub.ac.uk writes:
{Actually, I (jscotti@lpl.arizona.edu) wrote this:}
>> Not really screwy. The number of 50 meter objects is enhanced by
>> about 10 times and the Tunguska type events probably happen once
>> or a few times per century. Remember, 3 out of 4 enter over water
>> and may be less likely to be detected. Also, perhaps a large
>>
>
>
>I wonder... Could this be the explanation for the non-radioactive
>mushroom cloud seen by airline pilots in the Pacific one day in the
>late 70's - early 80's? It was never connected to any source that I
>am aware of.
I vaguely remember hearing something about this. The rate of small
asteroid impact could very well account for such an event. I doubt
we can conclusively identify it as an asteroid impact, but the
probability of such an event happening is quite high.
>Some theorized it was caused by an undersea volcanic explosion, but
>no one succeeded in associating it with one. It was not a nuclear
>explosion, although some at first suggested that. It is unlikely to
>have been a non-nuclear explosion, ie no ships disappeared and I'm
>not sure I see a motive for an experimental blast in that part of the
>world.
In the absence of further evidence, we'll just have to add small
asteroid impacts as a possibility.
>Just a thought, although I would not expect a mushroom cloud from
>such a comet strike. I'm not sure I can even see a mechanism for
>creating one from a Tunguska class strike.
The mechanism is quite understandable. You have an object moving
at hypersonic velocity as it enters the atmosphere. A stony or
stony iron object could easily survive into the low atmosphere where
the aerodynamical stress catastrophically ruptures it and it explodes
just like a bomb. The estimated impact energies of 10-100 meter
objects traveling at typical velocities is measured in the kilotons
on the small end to 10s of megatons on the large end and that kinetic
energy has to go somewhere! Smaller objects fracture high in the
atmosphere and appear as bright bolides which leave trails and
fragments along the way. If the object is strong enough, it might
survive largely intact with most of its kinetic energy and might
create an impact crater such as was made about 50,000 years ago when
the Diablo Canyon Meteor crater was formed in Arizona. That crater
is thought to have been formed by the impact of a stony iron object
only about 30 meters in diameter. Objects strong enough to survive
atmospheric entry are fortunately rare.
By the way, the Tuguska event was observed by residents of the
region and their description of the explosion matchs that of a nuclear
bomb blast quite closely.
Jim.
---------------------------------------------
Jim Scotti
{jscotti@lpl.arizona.edu}
Lunar & Planetary Laboratory
University of Arizona
Tucson, AZ 85721 USA
---------------------------------------------
------------------------------
Date: 4 Nov 1992 14:06 PST
From: SCOTT I CHASE <sichase@csa1.lbl.gov>
Subject: Heavy Boots, Again (was: NASA Coverup)
Newsgroups: sci.space,alt.conspiracy,sci.physics
In article <8ey167O00WB988Vo4Y@andrew.cmu.edu>, lc2b+@andrew.cmu.edu (Lawrence Curcio) writes...
>NASA is obviously covering this up because it would violate the heavy
>boots theory.
To those of you who watched _Space Age_ this past Monday: Do you remember
the clip they showed from the early Soviet fictional movie about a trip
to the Moon? The ship lands on the Moon, and out comes a bearded astronaut
jumps down to set foot on the Moon for the first time - WEARING HEAVY BOOTS!
His spacesuit clearly consists of a one-piece body suit, no helmet, and
very think platform shoes/boots. It was a clear attempt to explain why
the astronaut wouldn't just float away.
-Scott
--------------------
Scott I. Chase "It is not a simple life to be a single cell,
SICHASE@CSA2.LBL.GOV although I have no right to say so, having
been a single cell so long ago myself that I
have no memory at all of that stage of my
life." - Lewis Thomas
------------------------------
Date: Wed, 4 Nov 92 17:37:40 GMT
From: Allen Wallace <allen@dtint.dtint.com>
Subject: How to electronically detect X-RAYS???
Newsgroups: sci.electronics,sci.space,sci.space.shuttle,sci.physics
In article <1992Oct31.170935.1393@cactus.org> Charles Thompson,
thompson@cactus.org writes:
>I am looking for a sensitive X-ray detector.
>What is the best way to detect X-rays?
Another idea that comes to mind is to use neon bulbs. Neon lamps need
a photon or gamma ray to start the bulb. Some bulbs have a small amount
of radioactive "starter". Just put the bulb in a relaxation oscillator,
and
the flash rate should indicate light or gamma ray levels. You can use old
NIXIE neon tubes for more sensitivity because of their increased volume.
--
---
root root@dtint.dtint.com
Digital Technology Int. (801)226-2984
500 W. 1200 South, Orem UT, 84057 FAX (801) 226-8438
------------------------------
Date: Wed, 4 Nov 1992 19:26:00 GMT
From: "Doug S. Caprette Bldg. 28 W191 x3892" <dsc@gemini.tmc.edu>
Subject: Hubble's mirror
Newsgroups: sci.astro,sci.space
In article <yssPTB4w165w@bluemoon.rn.com> gerry@bluemoon.rn.com (Gerard M. Foley) writes:
>dhl@mrdog.msl.com (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.
>>
>> Thanks for any info.
>> --
>> Donald. Speaking only for myself.
>>
>> "You can't set glasses or a book on a door or a bathroom!" - djl
>
>It wasn't Rockwell (I forget axactly who it was, but it was an
>otherwise reputable New England outfit) and put briefly, they
>fouled up the test, performing it incorrectly, and never
>checked by any independent method.
>
Worse thatn that I'm afraid. They did a less precise check with a simpler
independent method, and found the error. Then, the difference was handwaved
away.
Also Kodak, which made the backup mirror, wanted the two of them to be
closely compared and the best of the two used. They were turned down on
this idea.
------------------------------
Date: Wed, 4 Nov 1992 22:32:01 GMT
From: Dan Pechonis <danp@oakhill.sps.mot.com>
Subject: Hubble's mirror
Newsgroups: sci.astro,sci.space
>> 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.
>
>It wasn't Rockwell (I forget axactly who it was, but it was an
>otherwise reputable New England outfit) and put briefly, they
>fouled up the test, performing it incorrectly, and never
>checked by any independent method.
>
I believe it was Perkin-Elmer Corporation. Sorry I don't know the details.
Dan Pechonis
danp@mammoth.sps.mot.com
------------------------------
Date: 4 Nov 1992 16:18:45 -0500
From: MIT Presidential Information Service <Surveys@campaign92.org>
Subject: Media Survey
Newsgroups: sci.space
Explanation: What you think about the media coverage of the recent presidential
election campaign? After our first electronic survey on Sunday, we have
corrected a number of bugs to make our form processor more user
friendly, and more reasonable in its responses. In this last
broad-distribution survey of our experiment, we would appreciate your
responses, if you care to participate. Please answer this survey and
return it to:
Surveys@Campaign92.Org
Results: The sooner you return this survey, the sooner you can find out
how your answers square with other participating members of the Internet
community. We will post the results to those who respond as soon as the
returns become significant.
Directions: Try to answer all the questions as best you can in order make
this survey as accurate as possible. Be sure to put your answer AFTER
the PROMPT for each query BUT NOT on new line. The answers to questions
will complete from your input, so you need only provide enough characters
to distinguish your answer from the alternatives. For multiple choice
questions with letter or numeric labels, you need only provide the letter
or number for your answer. Be careful NOT TO DELETE the FORM IDENTIFIER
and SPECIFIER appearing at the beginning of the survey, or the system
will have trouble figuring out which survey you are submitting.
If you are unsure how to complete this survey, you can learn how to fill
out our computerized forms by sending mail to:
Help@Campaign92.Org
Eligibility: Feel free to circulate this survey to your friends. Anyone
able to send electronic mail is eligible to participate, even if they
have never taken advantage of the MIT Presidential Information Servers.
Comments: If you wish to register comments on this survey or other aspects of
these experiments, you may send them to:
Commentary@Campaign92.Org
--------------------
PLEASE DO NOT DELETE THE NEXT LINE!
:FORM: MEDIA-SURVEY
Question: What was the most important event in the presidential campaign?
Answer: Select one: 1 the Buchanan primary challenge to Bush
2 Perot's entry, withdrawal and reentry
3 the Democratic convention
4 the Republican convention
5 the candidate debates
6 other
7 no single event
:MOST-IMPORTANT-FACTOR:
Question: How much attention did you pay to news programs on the
major television networks?
Answer: Select one: 1 paid a lot of attention
2 moderately attentive
3 paid no attention
:NETWORK-NEWS-ATTENTION:
Question: To what extent did news programs on major television
networks focus on issues that interest you?
Answer: Select one: 1 highly focused on issues of interest to me
2 focused on issues of interest to me
3 not focused on issues of interest to me
:NETWORK-NEWS-FOCUS:
Question: Against which candidate were news programs on major
television networks more biased?
Answer: Select one: 1 mostly biased against George Bush
2 mostly biased against Bill Clinton
3 mostly biased against Ross Perot
4 not biased against any candidate
:NETWORK-NEWS-BIAS:
Question: How much attention did you pay to news programs on the
local television?
Answer: Select one: 1 paid a lot of attention
2 moderately attentive
3 paid no attention
:LOCAL-NEWS-ATTENTION:
Question: To what extent did news programs on local television
focus on issues that interest you?
Answer: Select one: 1 highly focused on issues of interest to me
2 focused on issues of interest to me
3 not focused on issues of interest to me
:LOCAL-NEWS-FOCUS:
Question: Against which candidate were news programs on local
television more biased?
Answer: Select one: 1 mostly biased against George Bush
2 mostly biased against Bill Clinton
3 mostly biased against Ross Perot
4 not biased against any candidate
:LOCAL-NEWS-BIAS:
Question: How much attention did you pay to newspapers?
Answer: Select one: 1 paid a lot of attention
2 moderately attentive
3 paid no attention
:NEWSPAPER-ATTENTION:
Question: To what extent did newspapers focus on issues that
interest you?
Answer: Select one: 1 highly focused on issues of interest to me
2 focused on issues of interest to me
3 not focused on issues of interest to me
:NEWSPAPER-FOCUS:
Question: Against which candidate were newspapers more biased?
Answer: Select one: 1 mostly biased against George Bush
2 mostly biased against Bill Clinton
3 mostly biased against Ross Perot
4 not biased against any candidate
:NEWSPAPER-BIAS:
Question: How much attention did you pay to interview programs on
television?
Answer: Select one: 1 paid a lot of attention
2 moderately attentive
3 paid no attention
:INTERVIEW-ATTENTION:
Question: To what extent did interview programs on television
focus on issues that interest you?
Answer: Select one: 1 highly focused on issues of interest to me
2 focused on issues of interest to me
3 not focused on issues of interest to me
:INTERVIEW-FOCUS:
Question: Against which candidate were interview programs on
television more biased?
Answer: Select one: 1 mostly biased against George Bush
2 mostly biased against Bill Clinton
3 mostly biased against Ross Perot
4 not biased against any candidate
:INTERVIEW-BIAS:
Question: How much attention did you pay to the convention
coverage on television?
Answer: Select one: 1 paid a lot of attention
2 moderately attentive
3 paid no attention
:CONVENTION-ATTENTION:
Question: To what extent did the convention coverage on
television focus on issues that interest you?
Answer: Select one: 1 highly focused on issues of interest to me
2 focused on issues of interest to me
3 not focused on issues of interest to me
:CONVENTION-FOCUS:
Question: Against which candidate was convention coverage on
television more biased?
Answer: Select one: 1 mostly biased against George Bush
2 mostly biased against Bill Clinton
3 mostly biased against Ross Perot
4 not biased against any candidate
:CONVENTION-BIAS:
Question: How much attention did you pay to the debate commentary
on television?
Answer: Select one: 1 paid a lot of attention
2 moderately attentive
3 paid no attention
:DEBATE-ATTENTION:
Question: To what extent did the debate commentary on television
focus on issues that interest you?
Answer: Select one: 1 highly focused on issues of interest to me
2 focused on issues of interest to me
3 not focused on issues of interest to me
:DEBATE-FOCUS:
Question: Against which candidate was debate commentary on
television more biased?
Answer: Select one: 1 mostly biased against George Bush
2 mostly biased against Bill Clinton
3 mostly biased against Ross Perot
4 not biased against any candidate
:DEBATE-BIAS:
Question: During the last month of the campaign, about how often
did you see televised political ads for George Bush?
Answer: Select one: 1 almost every day
2 a few times a week
3 once a week
4 not at all
:BUSH-ADS:
Question: During the last month of the campaign, about how often
did you see televised political ads for Bill Clinton?
Answer: Select one: 1 almost every day
2 a few times a week
3 once a week
4 not at all
:CLINTON-ADS:
Question: During the last month of the campaign, about how often
did you see televised political ads for Ross Perot?
Answer: Select one: 1 almost every day
2 a few times a week
3 once a week
4 not at all
:PEROT-ADS:
Question: Were the Bush political ads you saw primarily about
George Bush's position on the issues or attacks on his
opponents?
Answer: Select one: 1 mostly issues
2 mostly attack
3 can't say
:BUSH-AD-TYPE:
Question: Were the Clinton political ads you saw primarily about
Bill Clinton's position on the issues or attacks on his
opponents?
Answer: Select one: 1 mostly issues
2 mostly attack
3 can't say
:CLINTON-AD-TYPE:
Question: Were the Perot political ads you saw primarily about
Ross Perot's position on the issues or attacks on his
opponents?
Answer: Select one: 1 mostly issues
2 mostly attack
3 can't say
:PEROT-AD-TYPE:
Question: Which candidate was most responsible for negative
campaigning?
Answer: Select one: 1 George Bush
2 Bill Clinton
3 Ross Perot
:NEGATIVE-CAMPAIGN:
Question: How much of the first presidential debate did you
watch?
Answer: Select one: all most some none
:FIRST-PRESIDENTIAL-DEBATE:
Question: How much of the second presidential debate did you
watch?
Answer: Select one: all most some none
:SECOND-PRESIDENTIAL-DEBATE:
Question: How much of the third presidential debate did you
watch?
Answer: Select one: all most some none
:THIRD-PRESIDENTIAL-DEBATE:
Question: Which debate format did you prefer?
Answer: Select one: 1 panel of journalists - 1st presidential
2 single moderator - vice-presidential
3 audience questions - 2nd presidential
4 single moderator & journalist panel
- 3rd presidential
:DEBATE-FORMAT:
--------------------
The Presidential Campaign Information Service is a non-partisan
service operated at M.I.T to make campaign information available,
facilitate electronic discussion of the issues, and to study the
use of electronic mail as a component of a presidential campaign.
The service can neither control who reads what you write in public,
nor how they may use your written words. For our part, we store
most messages, and we will make them available after the election
for scientific study. Names and any other identifiers will not be
released; they will be omitted or replaced with random symbols.
Eric Loeb and John Mallery
M.I.T. Artificial Intelligence Laboratory
------------------------------
Date: Wed, 4 Nov 1992 20:55:20 GMT
From: Mark 'Henry' Komarinski <komarimf@craft.camp.clarkson.edu>
Subject: NASA Coverup
Newsgroups: sci.physics,sci.space,alt.conspiracy
Anyone got a toaster for this guy?
snarfy@cruzio.santa-cruz.ca.us writes:
> [garbage erased]
> In one sixth gravity , a 180 pound man would weigh a mere 30 pounds.
> 6/180 = 30
> [even more garbage deleted]
> weight. Therefore , they should have been able to jump far higher than
> they could on the earth without any difficulty. The average person can
> jump about 18 inches vertically without a run. On all of the video
> footage shot by the astronauts while in the moonwalking mode , the
> highest leaps performed by the most vigorous individuals, such as John
> Young, never amounted to more than about 18 inches, while they were
> THEORETICALLY CAPABLE OF SLOW BACKFLIPS!
You mean besides the fact that they can barely move to begin with? Here,
I'll wrap you up in a straight jacket and see how well you can wave your
arms around.
> Another thing. The practical design of a spacesuit would dictate that
> economy of weight be a prime consideration, for the purposes of
> maximizing payloads. The value of 185 pounds cannot be accounted for
> unless you attribute most of this weight to some mysteriously heavy
> equipment in the the backpack. While a Scuba diver's dual tanks weigh in
> at about 80 pounds and are designed to aid the diver in sinking to the
> bottom , presumably the astronaut's air containment system would be
> significantly lighter. If we allow 40 pounds for air containment, 20
> pounds for a hefty battery , and 40 or so pounds for lightweight heat
> pumps and the like ,that leaves 85 pounds for the suit itself . This is
> just not a believable figure judging from the general appearance of
> flexibilty of the material.
Plus weight for food, water, containment systems for 'excrements' (you do have
to take a leak, even on the moon), radio, cooling system, plus supports
for places that the material just can't cover, like where the gloves
connect to the suit, and where the bottom of the suit connects to the
top, etc. Also, this material is not that light. You're talking about
protecting soemone from absolute nothing around him. I'd make it rather
thick, no matter what the weight. A few safety features too, probably
emergency radio, backup air and other systems.
> ["V" garbage deleted]
Wear a heavy backpack and you'll tip back. Wear something heavy on your
front and you'll tip forward. Wear something equally heavy on both
the front and back you won't tip. Simple mechanics. But I'd guess you
never passed Physics I.
> During Apollo 17 , astronauts Cernan and Scmitt began their first
> assignment by deploying and loading the Rover . Cernan apparently became
> quite excited and his Capsule Communicator , astronaut Parker warned him
> that his metabolic rate was going up. That meant that he was using more
> oxygen. Cernan replied that he never felt calmer in his life and
> indicated to Parker that he would take it easy . He mentioned to Parker
> that he thought that it was due to getting accustomed to handling himself
> in "zero g".
> Parker, an astronomer, then stated that he thought Cernan was working at
> 1/6 gravity. Cernan's reply was "Yes. You know where we are....whatever."
> This remark suggests that Cernan wanted to avoid the discussion. Perhaps
> Parker was not aware of the high gravity situation and asked an
> embarrassing question.
To anyone who has just lost 5/6 of their weight, I'd bet it would seem
a lot like zero g. Have you ever made a freudian slip??
I'm actually amazed you didn't think that the CIA faked the moon landings.
Get a grip on reality.
-Mark
--
- Mark Komarinski - komarimf@craft.camp.clarkson.edu
[MIME mail welcome]
The only candidate worth voting for is Bill the Cat. He might not
do good, but that's never been a requirement.
------------------------------
Date: 4 Nov 92 18:36:00 GMT
From: Elling Olsen <elling.olsen@thcave.no>
Subject: NASA COVERUP
Newsgroups: sci.space
Harry,
HS> Oh, come now. A conspiracy that large, held together for that long?
HS> a government that couldn't suppress Watergate or Iranscam? Come now
HS> This is laughable.
Why don't you do some work and disprove the claim that the
earth/moon neutral point have changed from 20,000-25,000 miles
to 43,495 miles from the center of the moon? Or is it more
confortable to sit in your couch judging and laughing?
Elling
------------------------------
Date: 4 Nov 92 18:36:00 GMT
From: Elling Olsen <elling.olsen@thcave.no>
Subject: NASA COVERUP
Newsgroups: sci.space
Snarfy,
S> The July 25th , 1969 issue of TIME magazine stated that the neut
S> point was 43,495 miles from the center of the moon. Werner von
S> stated in the 1969 edition of "History of Rocketry and Space Trave
S> the neutral point was 43,495 miles the center of the moon
S> pre-Apollo distances were given as 20,000 to 25,000 miles from the
S> of the moon. NASA , it appears, had re-calculated the neutral
S> which would indicate that the moon's gravity is not 1/6th, as New
S> stated.
If it is true that the neutral point between earth and moon has
changed during the space exploration, it is highly
interresting. My physics books have not changed....
Elling
------------------------------
Date: 4 Nov 92 22:30:40 GMT
From: Tarl Neustaedter <tarl@sw.stratus.com>
Subject: NASA Coverup
Newsgroups: sci.space,alt.conspiracy,alt.sci.physics.new-theories
Note followup ... Since this involves claiming everyone is lying, the
discussion should take place off in a group dedicated to that purpose.
Alt.sci.physics.new-theories seems to fit the bill.
In article <4578@cruzio.santa-cruz.ca.us>, snarfy@cruzio.santa-cruz.ca.us writes:
> [...]
> This calculation is apparently based on the observed distance of 2903
> miles of the earth's distance from the earth-moon barycenter as that
> [...]
> the gravitational forces of the earth-moon system balance,was given over
> and over again as being between 22,100 and 25,200 miles from the surface
> of the moon in the direction of the earth.
> [...]
> The figure of 43,495 miles from the moon's center for the neutral point
You seem to have some confusion of what "Neutral Point" means. The Barycenter
(center of mass between earth and moon) is directly observable by the motion
of the earth. It lies about 4700 km from the earth's center, or about 2000km
under your feet. The Lagrange L2 point (between earth and moon, where
gravitational acceleration between earth and moon balance) is 43,000 km from
the center of the moon.
These numbers agree with the first two quotes. The third quote is clearly
a typo where someone meant to say "kilometers" and said miles. Given that
this was from Time Magazine, it's clear where the fuckup was.
As for the derivation of these numbers; the barycenter is directly observable
due to the earth's motion. If you feel that the measurement was incorrect,
please submit new observations that show a different value. From that one
value (4728 km from center of the earth), we'll derive all the rest of the
numbers. If you want specific explanations, send me email or followup in
alt.sci.physics.new-theories (I do read that group).
Mass of earth: 5.96e24 kg ~ (9.78 * 6.378e6^2 / 6.67e-11)
Earth-moon distance: 384,400 km (average)
Barycenter distance: 4728 km
Mass ratio Earth/moon: 81.295 (3.84e5/4.7e3)
L2 distance from moon cent.: 42589km (3.84e5/sqrt(81.295))
Mass of moon: 7.35e22 kg (5.96e24/81.295)
Radius of moon: 1.738e3 km (31 arc min at 384,400 km)
Gravity on moon: 1.62 m/s^2 (6.67e-11 * 7.35e22 / 1.738e6^2)
1.62 m/s^2 comes awful damn close to 1/6th of 9.78 m/s^2.
I notice I didn't derive the earth-moon distance. Let's do that now:
Formula for converting orbital period to distance is:
a = (G * (M1 + M2) * T^2 / 4 pi^2) ** 1/3
siderial period of moon(T): 2360534 s (27.031 days)
M1 is Mass of Earth, and we'll ignore the moon's mass)
a^3 = 6.67e-11 * 5.96e24 * 5.572e12 / 39.47
a = 5.61e25 ^ 1/3 = 3.82e8 m.
Error in third decimal induced by ignoring moon's mass, which we hadn't
derived yet.
--
Tarl Neustaedter tarl@sw.stratus.com
Marlboro, Mass. Stratus Computer
Disclaimer: My employer is not responsible for my opinions.
------------------------------
Date: 4 Nov 92 17:47:01 GMT
From: Dennis Newkirk <dennisn@ecs.comm.mot.com>
Subject: Russian Engines for DC-Y?
Newsgroups: sci.space
In article <Bx5uDG.FEq@news.cso.uiuc.edu> jbh55289@uxa.cso.uiuc.edu (Josh 'K' Hopkins) writes:
>
>The article mentions the RD-701 which uses kerosene, LOX and hydrogen. I assume
>this is a cryogenic engine. I believe that the Russians recently started
>operating a cryogenic engine somewhere, so it would be a good bet the Energomash
>has one already built.
>Josh Hopkins jbh55289@uxa.cso.uiuc.edu
Your probably thinking of the LH/LOX RD-0120 used on the Energia core.
The new upper stage for the Proton may also be LH/LOX, but I don't
have my files handy to confirm this.
Dennis Newkirk (dennisn@ecs.comm.mot.com)
Motorola, Land Mobile Products Sector
Schaumburg, IL
------------------------------
Date: Wed, 4 Nov 92 21:30:02 EST
From: John Roberts <roberts@cmr.ncsl.nist.gov>
Subject: Vacuum gloves
-From: higgins@fnalo.fnal.gov (Bill Higgins-- Beam Jockey)
-Subject: Gloveless in Vacuum? (was Re: Man in space ... )
-Date: 4 Nov 92 15:34:38 GMT
-In article <720796989snx@osea.demon.co.uk>, andy@osea.demon.co.uk (Andrew Haveland-Robinson) writes:
->> What will happen if the space suite of an austronaut gets ripped in space ?
-> Well Nick, my feeling is that he would nearly explode.
-*Bzzt* Wrong, but thank you for playing...
-Ever put your hand up against the nozzle of vacuum cleaner? Your skin
-will hold about 1 atmosphere pressure nicely.
-The reason I'm writing, instead of just allowing the discussion to
-peter out, is to mention that a suggestion of Hermann Oberth's:
-Astronauts might wear spacesuits without gloves for delicate work!
-He reasoned that your skin can stand up to low pressure without major
-medical problems, so maybe you could work without pressure gloves in
-space. You'd have to wear thin gloves for thermal and UV protection,
-and making a good wrist seal on your spacesuit might be tough-- but
-maybe not as hard as the problem of making a really flexible pressure
-glove! I think this was in his Fifties book *Man in Space*.
Correction (this is NIST - we don't 'Bzzt' here :-) : Henry says that the
human skin can withstand a pressure differential of at least a few hundred
millimeters of mercury, *provided* you have mechanical support to prevent
the underlying tissues from swelling. Without that, I doubt your hands would
be usable for more than a few minutes at best.
Check the references on skintight suits - I'm not sure whether the exact
structure of the gloves is described.
John Roberts
roberts@cmr.ncsl.nist.gov
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End of Space Digest Volume 15 : Issue 380
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