Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_5/V16NO509.TXT

Internet Message Format | 1993-07-13 | 32KB

Date: Sun,  2 May 93 05:34:28
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #509
To: Space Digest Readers
Precedence: bulk


Space Digest                Sun,  2 May 93       Volume 16 : Issue 509

Today's Topics:
                       Deployable Space Dock..
                Gamma Ray Bursters.  WHere  are they.
                           HST Antenna OK?
         HST Servicing Mission Scheduled for 11 Days (5 msgs)
                          Internet resources
                   moon image in weather sat image
                    Philosophy Quest.  How Boldly?
                             Rocket Types
               Satellite around Pluto Mission? (2 msgs)
                     temperature of the dark sky
                     TRUE "GLOBE", Who makes it?
               U.S. Government and Technolgy Investment
                         Vandalizing the sky.
                      What planets are habitable

    Welcome to the Space Digest!!  Please send your messages to
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----------------------------------------------------------------------

Date: Fri, 30 Apr 1993 15:41:25 GMT
From: Henry Spencer <[e-mail]>
Subject: Deployable Space Dock..
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>Why not build a inflatable space dock.

If you're doing large-scale satellite servicing, being able to do it in
a pressurized hangar makes considerable sense.  The question is whether
anyone is going to be doing large-scale satellite servicing in the near
future, to the point of justifying development of such a thing.

>...inflate the dock with a gas (is does not have to be oxygen, just neeeds to
>be non-flameble, non-damaging to the satellite and abel to maintain heat)...

You'd almost certainly use air.  Given that you have to pressurize with
*something*, safety considerations strongly suggest making it breathable
(even if the servicing crew is using oxygen masks for normal breathing,
to avoid needing a ventilation system, it's nice if the hangar atmosphere
is breathable in a pinch -- it makes mask functioning much less critical).
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

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

Date: 30 Apr 1993 11:53:45 -0400
From: Pat <[e-mail]>
Subject: Gamma Ray Bursters.  WHere  are they.
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
|In article <1rlrpv$[e-mail]>, [e-mail] (Pat) writes...
|>Is this a big enough problem, to create a new area of physics?
|>just a little speculative thinking folks.
|>pat
|Well pat for once I agree with you and I like your first idea that you had.
>IT probably is the gamma ray signature of the warp transitions of interstellar
>spacecraft! :)


Dennis.

    WE agree a lot ,  it's just we don't both post when we agree
on something.  And when we disagree, it tends to be a lot more
noticeable.;-)

pat

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

Date: 30 Apr 1993 16:05:24 GMT
From: Steve Derry <[e-mail]>
Subject: HST Antenna OK?
Newsgroups: sci.space,sci.astro

I haven't seen any mention of this in a while, so here goes...

When the Hubble Telescope was first deployed, one of its high gain antennas
was not able to be moved across its full range of motion.  It was suspected
that it had been snagged on a cable or something.  Operational procedures
were modified to work around the problem, and later problems have overshadowed
the HGA problem.

Is there any plan to look at the affected HGA during the HST repair mission,
to determine the cause of its limited range of motion?  Is the affected HGA
still limited, or is it now capable of full range of motion?

--
Steve Derry
<[e-mail]>

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

Date: Fri, 30 Apr 1993 15:10:54 GMT
From: [e-mail]
Subject: HST Servicing Mission Scheduled for 11 Days
Newsgroups: sci.space,sci.space.shuttle,sci.astro

In article <1rq3os$[e-mail]>, [e-mail] (Pat) writes:
> In article <[e-mail]> [e-mail] (Greg Moore) writes:
> |
> |    As Herny pointed out, you have to develop the thruster.
> |Also, while much lighter, you still have to lift the mass of
> |the thruster to orbit, and then the thruster lifts its own
> |weight into a higher orbit.  And you take up room in the payload
>>bay.
>>
>
> a yes,  but the improvement in  boost orbit to the HST is Significant,

I do not understand what you are saying here.  What is improved, what
is Significant, and what does this have to do with carrying more
equipment on a servicing mission?  Also, as implied by other posters, why
do you need to boost the orbit on this mission anyway?  Maybe you have
something here, but could you please clarify it for us on the net?

> and  that means you can then carry EDO packs  and enough consumables
> so the SHuttle mission can go on long enough to also fix the
> array tilt motors,  and god knows what else  is going to wear out

From what I've heard, the motors are fine - it is one of the two
sets of electronics that control the motors that needs a fix.  The
motors and electronics are separate pieces of hardware.  I expect
to be corrected if I'm wrong on this.

> on the HST in the next 9 months.
>
> pat
>

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

Date: 30 Apr 1993 11:34:31 -0400
From: Pat <[e-mail]>
Subject: HST Servicing Mission Scheduled for 11 Days
Newsgroups: sci.space,sci.space.shuttle,sci.astro

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>
>No, the thing is designed to be retrievable, in a pinch.  Indeed, this
>dictated a rather odd design for the solar arrays, since they had to be
>retractable as well as extendable, and may thus have indirectly contributed
>to the array-flapping problems.


Why not design the solar arrays to be detachable.  if the shuttle is going
to retunr the HST,  what bother are some arrays.  just fit them with a quick release.

one  space walk,  or use the second canadarm to remove the arrays.

pat

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

Date: 30 Apr 1993 11:47:04 -0400
From: Pat <[e-mail]>
Subject: HST Servicing Mission Scheduled for 11 Days
Newsgroups: sci.space,sci.space.shuttle,sci.astro

In article <[e-mail]> [e-mail] writes:
>In article <1rq3os$[e-mail]>, [e-mail] (Pat) writes:
>> In article <[e-mail]> [e-mail] (Greg Moore) writes:
|> |
|> |    As Herny pointed out, you have to develop the thruster.
|> |Also, while much lighter, you still have to lift the mass of
|> |the thruster to orbit, and then the thruster lifts its own
|> |weight into a higher orbit.  And you take up room in the payload
|>>bay.
|>>
|>
|> a yes,  but the improvement in  boost orbit to the HST is Significant,
|
|I do not understand what you are saying here.  What is improved, what
|is Significant, and what does this have to do with carrying more
|equipment on a servicing mission?  Also, as implied by other posters, why
|do you need to boost the orbit on this mission anyway?  Maybe you have
|something here, but could you please clarify it for us on the net?
|

RIght now the HST sevicing mission is listed as 11 days.  before
it was listed as 9 days.  they just kicked up the number of spacewalks
to 5,  after simulations indicated  that it was not do-able in 4.

After all the space walking,  they are going to  re-boost the HST's
orbit.  I think right now  it's sitting  at 180 miles up,
they would like  220.  I don't know the exact orbit numbers.
I know when HST was first flown, it was placed in the Highest
possible Shuttle orbit.

Now the shuttle can cary a thing called the EDO pallet, or extended
duration orbiter pallet.  It's mostly  LOX/LH for the fuel cells
and RCS gear,  plus more O2  and canisters for the life support
re-breathers.  maybe more nitrogen too.

THe limit on space-walking is a function of suit supplies (MASS)
and Orbiter Duration.

In order to perform the re-boost of the HST, the OMS engines
will be fired for a long period.  Now the shuttle is a heavy
thing.  THe HST isn't light either.  THe amount of OMS fuel
needed to fly both up is substantial.   a small booster
carried up and used to boost HST on it's own will weigh significantly
less then the OMS fuel required to Boost  both HST and SHUttle,
for a given orbital change.

From what i understand,  the mass margins on the HST missions are
tight enough they can't even carry extra Suits or MMU's.

Now if they used a small tug,  I would bet,  just a wild guess,
that the savings on amss margin  would allow carrying the
EDO pallet,  extra suits,  more consumables,  parts for the
flaky FGS sensor,  parts for the balky solar  electronics,

and still enough for a double magnum of champagne.

or the HST could even get placed into  some sort of medium orbit.
The reason they want a high orbit, is less antenna pointing,
and longer drag life.

|> and  that means you can then carry EDO packs  and enough consumables
|> so the SHuttle mission can go on long enough to also fix the
|> array tilt motors,  and god knows what else  is going to wear out
|
|From what I've heard, the motors are fine - it is one of the two
|sets of electronics that control the motors that needs a fix.  The
|motors and electronics are separate pieces of hardware.  I expect
|to be corrected if I'm wrong on this.
|

a
Whatever it is,  the problem in the tilt array is a big constraint
on HST ops.

pat

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

Date: 30 Apr 1993 16:24:51 GMT
From: Steve Derry <[e-mail]>
Subject: HST Servicing Mission Scheduled for 11 Days
Newsgroups: sci.space,sci.space.shuttle,sci.astro

Pat ([e-mail]) wrote:
: THe limit on space-walking is a function of suit supplies (MASS)
: and Orbiter Duration.

: In order to perform the re-boost of the HST, the OMS engines
: will be fired for a long period.  Now the shuttle is a heavy
: thing.  THe HST isn't light either.  THe amount of OMS fuel
: needed to fly both up is substantial.   a small booster
: carried up and used to boost HST on it's own will weigh significantly
: less then the OMS fuel required to Boost  both HST and SHUttle,
: for a given orbital change.

: From what i understand,  the mass margins on the HST missions are
: tight enough they can't even carry extra Suits or MMU's.

: pat

I haven't seen any specifics on the HST repair mission, but I can't see why
the mass margins are tight.  What are they carrying up?  Replacement components
(WFPC II, COSTAR, gyros, solar panels, and probably a few others), all sorts of
tools, EVA equipment, and as much OMS fuel and consumables as they can.  This
should be lighter than the original HST deployment mission, which achieved the
highest altitude for a shuttle mission to date.  And HST is now in a lower
orbit.

Seems like the limiting factors would be crew fatigue and mission complexity.

--
Steve Derry
<[e-mail]>

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

Date: Fri, 30 Apr 1993 15:57:33 GMT
From: Henry Spencer <[e-mail]>
Subject: HST Servicing Mission Scheduled for 11 Days
Newsgroups: sci.space,sci.space.shuttle,sci.astro

In article <[e-mail]> [e-mail] writes:
>... Also, as implied by other posters, why
>do you need to boost the orbit on this mission anyway? ...

You don't *need* to, but it's desirable.  HST, like all satellites in
low Earth orbit, is gradually losing altitude due to air drag.  It was
deployed in the highest orbit the shuttle could reach, for that reason.
It needs occasional reboosting or it will eventually reenter.  (It has
no propulsion system of its own.)  This is an excellent opportunity,
given that there may not be another visit for several years.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

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

Date: Fri, 30 Apr 93 15:20:29 BST
From: Ata Etemadi <[e-mail]>
Subject: Internet resources
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] writes:
-| I am taking a course entitled "Exploring Science Using Internet".
-| For our final project, we are to find a compendium of Internet resources
-| dealing with a science-related topic. I chose Astronomy. Anyway, I was
-| wondering if anyone out there knew of any interesting resources on Internet
-| that provide information on Astronomy, space, NASA, or anything like that.
-|
-| THANKS!
-|
-|   KEITH MALINOWSKI
-|   [e-mail]
-|   P.O. Box 2472
-|   Stockton State College
-|   Pomona, New Jersey 08240

Try doing a keyword search under Gopher using Veronica or accessing a
World Wide Web server. Also finger [e-mail] for a list
of Internet resources which includes 2-3 sites with Space-specific
information. I am sure Ron Baalke will have told you about what is
available at JPL etc..

    best regards
        Ata <(|)>.
--
| Mail          Dr Ata Etemadi, Blackett Laboratory,                          |
|               Space and Atmospheric Physics Group,                          |
|               Imperial College of Science, Technology, and Medicine,        |
|               Prince Consort Road, London SW7 2BZ, ENGLAND                  |
| Internet/Arpanet/Earn/Bitnet [e-mail] or [e-mail]  |
| Span                              SPVA::atae       or     MSSLC:atae        |
| UUCP/Usenet                       [e-mail]        |

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

Date: Fri, 30 Apr 1993 16:48:44 GMT
From: George Wm Turner <[e-mail]>
Subject: moon image in weather sat image
Newsgroups: sci.astro,sci.space,sci.geo.meteorology,sci.geo.geology

an image of the moon has been caught in a weather satellite images of the earth.
it appears in both the 0430-1500UT ir and visual images of the earth.
the GIF images can be down loaded from vmd.cso.uiuc.edu and are named
CI043015.GIF and CV043015.GIF for the IR and visual images respectively.

pretty cool pictures;  in the ir it's saturated but in the visual image
details on the moon are viewable.

the moon is not in the 1400UT images.


 george wm turner            [e-mail]

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

Date: Fri, 30 Apr 1993 13:14:58 GMT
From: Doug Loss <[e-mail]>
Subject: Philosophy Quest.  How Boldly?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Bob Kierski) writes:
>
>
>There are a number of Philosophical questions that I would like to ask:
>
>1)  If we encounter a life form during our space exploration, how do we
>determine if we should capture it, imprison it, and then discect it?
>
   Analog SF magazine did an article on a similar subject quite a few
years ago.  The question was, if an alien spacecraft landed in
Washington, D.C., what was the proper organization to deal with it: The
State Department (alien ambassadors), the Defense Department (alien
invaders), the Immigration and Naturalization Service (illegal aliens),
the Department of the Interior (new non-human species), etc.  It was
very much a question of our perception of the aliens, not of anything
intrinsic in their nature.  The bibliography for the article cited a
philosophical paper (the name and author of which I sadly forget; I
believe the author was Italian) on what constitutes a legal and/or moral
person, i.e., a being entitled to the rights normally accorded to a
person.  The paper was quite interesting, as I recall.

>2)  If we encounter a civilization that is suffering economicly, will
>we expend resources from earth to help them?
>
   I think you'd have to be very careful here if the answer is yes.  The
human track record on helping those poor underpriveleged cultures (does

underpriveleged mean not having enough priveleges?) is terrible.  The
usual result is the destruction or radical reorganization of the
culture.  This may not always be wrong, but that's the way to bet.

>3)  With all of the deseases we currently have that are deadly and undetectable,
>what will be done to ensure that more new deadly deseases aren't brought
>back, or that our deseases don't destroy life elsewhere?
>
>--
>Have a day,
>
>  @   @
>   ( )     bobo

Doug Loss
[e-mail]

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

Date: Fri, 30 Apr 1993 15:37:16 GMT
From: Henry Spencer <[e-mail]>
Subject: Rocket Types
Newsgroups: sci.space

In article <1rpv9o$[e-mail]> [e-mail] (Glen Justin Balmer) writes:
>It said that in the 60's they developed a rocket that used ions or nuclear
>particles for propolsion.
>The government however, didn't give them $1billion for the developement...

I'd guess this was a garbled report of the NERVA effort to develop a
solid-core fission rocket (the most mundane type of nuclear rocket).
That was the only advanced-propulsion project that was done on a large
enough scale to be likely to attract news attention.  It *could* be any
number of things -- the description given is awfully vague -- but I'd
put a small bet on NERVA.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

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

Date: 30 Apr 1993 14:56:17 GMT
From: Rob Unverzagt <[e-mail]>
Subject: Satellite around Pluto Mission?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
> Being wierd again, so be warned:

Being what?  Oh, _weird_.  OK, I'm warned!

> Is there a plan to put a satellite around each planet in the solar system to
> keep watch? I help it better to ask questions before I spout an opinion.

Keep watch for what?

> How about a mission (unmanned) to Pluto to stay in orbit and record things
> around and near and on Pluto.. I know it is a strange idea, but why not??

Oh, the several tens (or hundreds) of millions of dollars it would cost
to "record things" there.  And I'd prefer a manned mission, anyway.

> It could do some scanning of not only Pluto, but also of the solar system,
> objects near and aaroundpluto, as well as SETI and looking at the galaxy
> without having much of the solar system to worry about..

We've already got a pretty good platform to "scan" the solar
system, as well as SETI and looking at the galaxy without having
much of the solar system to worry about..
Care to guess where it is?

Shag

--
----------------------------------------------------------------------
       Rob Unverzagt        |
  [e-mail]   |       Tuesday is soylent green day.
[e-mail] |

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

Date: Fri, 30 Apr 1993 15:53:29 GMT
From: Henry Spencer <[e-mail]>
Subject: Satellite around Pluto Mission?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>Is there a plan to put a satellite around each planet in the solar system to
>keep watch? ...

There would be some point to doing long-term monitoring of things like
particles and fields, not to mention atmospheric phenomena.  However,
there is no particular plan to establish any sort of monitoring network.
To be precise, there is no particular plan, period.  This is a large
part of the problem.  In this context, it's not surprising that unexciting
but useful missions like this get short shrift at budget time.  The closest
approach to any sort of long-term planetary monitoring mission is the
occasional chance to piggyback something like this on top of a flashier
mission like Galileo or Cassini.

>How about a mission (unmanned) to Pluto to stay in orbit and record things
>around and near and on Pluto...

It is most unlikely that there is much happening on Pluto that would be
worth monitoring, and it is a prohibitively difficult mission to fly
without new propulsion technology (something the planetary community
has firmly resisted being the guinea pigs for).  The combined need to
arrive at Pluto within a reasonable amount of time, and then kill nearly
all of the cruise velocity to settle into an orbit, is beyond what can
reasonably be done with current (that is, 1950s-vintage) propulsion.

>It could do some scanning of not only Pluto, but also of the solar system,
>objects near and aaroundpluto, as well as SETI and looking at the galaxy
>without having much of the solar system to worry about..

Most of this can be done just about as well from Earth.  The few things
that can't be, can be done better from a Voyager-like spacecraft that is
*not* constrained by the need to enter orbit around a planet.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

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

Date: Fri, 30 Apr 1993 16:39:59 GMT
From: Steve Willner <[e-mail]>
Subject: temperature of the dark sky
Newsgroups: sci.astro,sci.space

In article <[e-mail]>,
[e-mail] (Stupendous Man) writes:
>    If that's the case, let me point out that interstellar dust and
> molecules provide many instances of things that are, well, not-too-far
> from being blackbodies.  Many different observations, including IRAS
> and COBE, have determined that interstellar dust grain temperatures
> can range from 40K to 150K.

Interstellar grains are not at all close to blackbodies.  The "large"
grains have sizes of order 0.1 micron and absorb visible light with
fair efficiency.  However, at temperatures below 100 K, 90% of the
thermal emission will be beyond 22 microns, where radiating
efficiency is poor.  (A small antenna cannot easily radiate at long
wavelengths.)  Thus the grains must heat up more in order to radiate
the energy they have absorbed.

Moreover, the IRAS observations had a maximum wavelength of 100
microns.  Grains colder than 30 K will radiate primarily at longer
wavelengths, and IRAS would be relatively insensitive to them.  In
the extreme limit, grains as cold as 5 K will be almost undetectable
by any conceivable observation.

Worse still, IRAS color temperatures are heavily contaminated by a
population of "small" grains.  These grains have only perhaps 50
atoms, and when they are hit by a single photon they heat up to
temperatures of several hundred or 1000 K.  Of course they cool
quickly and then stay cold for a while, but _when they are radiating_
the characteristic temperature is several hundred K.  Even a small
population of these grains can dramatically raise the observed
"average" temperature.

A model for local infrared emission consistent with COBE data has
three components.  These represent scattered radiation from Zodiacal
dust (color temperature 5500 K), thermal emission from Zodiacal dust
(Tc = 280 K), and thermal emission from Galactic dust (Tc=25 K).  At
the ecliptic poles, the emissivities or dilution factors are
respectively 1.9E-13, 4E-8, and 2E-5.  The first two are roughly
doubled in the ecliptic plane.

To find the thermal equilibrium temperature, we add up the dilution
factor times the fourth power of temperature for all components, then
take the fourth root.  In the table below, starlight comes from
Allen's number that stellar emission from the whole sky is equivalent
to 460 zero mag stars with B-V color of 0.75.  No doubt careful work
could do much better.  (The person who suggested starlight had a
dilution factor of E-4 must have been remembering wrong.  We would be
cooked if that were the case.  In any event, the energy density of
starlight comes out about the same as that of the microwave
background, and I believe that to be correct.)

                         Dilution   Temp.   DT^4
Microwave background         1        2.7     53
Galactic dust              2E-5      25        8
Zodiacal dust (emission)   6E-8     280      369
Zodiacal dust (scattering) 3E-13   5500      275
Starlight                  1E-13   5500       92
                                           -----
                                             797

The fourth root of 797 is 5.3 K.  Outside the Solar system, the
result would be 3.5 K.

I find these results surprising, especially the importance of
Zodiacal dust, but I don't see any serious mistakes.

--
Steve Willner            Phone [phone]         Bitnet:   willner@cfa
Cambridge, MA 02138 USA                 Internet: [e-mail]
  member, League for Programming Freedom; contact [e-mail]

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

Date: Mon, 26 Apr 1993 18:13:37 GMT
From: Terry F Figurelle <[e-mail]>
Subject: TRUE "GLOBE", Who makes it?
Newsgroups: sci.space

In article [e-mail], [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Bill Vance) writes:
>>It has been known for quite a while that the earth is actually more pear
>>shaped than globular/spherical.  Does anyone make a "globe" that is accurate
>>as to actual shape, landmass configuration/Long/Lat lines etc.?
>
>I don't think you're going to be able to see the differences from a sphere
>unless they are greatly exaggerated.  Even the equatorial bulge is only
>about 1 part in 300 -- you'd never notice a 1mm error in a 30cm globe --
>and the other deviations from spherical shape are much smaller.
>--
>SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
>between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

I remember a physic prof. who talked about scaling a cue ball to Earth size.
Its was significantly less spherical that the Earth!

---
Terry F Figurelle            Boeing Defense & Space Group
email: [e-mail]        PO BOX 3999, Mail Stop 6J-EA
phone: [phone] fax:[phone]    Seattle, WA 98124-2499

--
Terry F Figurelle            Boeing Defense & Space Group
email: [e-mail]        PO BOX 3999, Mail Stop 6J-EA
phone: [phone] fax:[phone]    Seattle, WA 98124-2499

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

Date: Fri, 30 Apr 1993 15:10:33 GMT
From: [e-mail]
Subject: U.S. Government and Technolgy Investment
Newsgroups: sci.space,talk.politics.space

People who criticize "big Government" and its projects rarely seem to
have a consistent view of the role of Government in science and
technology.  Basically, the U.S. Government has gotten into the role of
supporting research which private industry finds too expensive or too
long-term.

(Historically, this role for the U.S. Gov't was forced upon it because
of socialism in other countries.  In order for U.S.  industries to
compete with government-subsidized foreign competitors, the U.S. Gov't
has taken on the role of subisizing big-ticket or long-lead R&D.)

As a Republican, I abhor the necessity for our Government to involve
itself in technology this way.  I believe that market forces should
drive technology, and the world would be a better place for it.  But
the whole world would have to implement this concept simultaneously, or
some countries would have subsidized R&D, while others would not.  So
the U.S. must subsidize because everybody else does.  (This sounds a
lot like the farm subsidies arguments behind our GATT negotiations,
doesn't it?)

But this role of Government subsidies is antithetical to
cost-effectiveness.  The general idea is to spend money on new
technology, and thereby maintain and promote our technological culture,
despite the forces in the business world (like the dreaded quarterly
earnings report) which erode the ability of U.S. industry to invest in
new technology.  And since our goal is to spend money, it makes little
sense to try to save money.

Of course, we could always spend our money more wisely, but EVERYBODY
disagrees about that the wisdom should be.

It's interesting to note that some of our best tools for cost control
available in industry today were derived from Government projects.
GANTT charts, CP/M, and most of the modern scheduling software comes
from DoD projects and their contractors.  The construction industry
has taken these tools to the core of their businesses; every large
construction project now uses these tools.

-- Ken Jenks, NASA/JSC/GM2, Space Shuttle Program Office
      [e-mail]  [phone]

     "A scientist can discover a new star, but he cannot make one.
      He would have to ask an engineer to do that."
        -- Gordon L. Glegg, American Engineer, 1969

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

Date: 30 Apr 1993 12:24:11 -0400
From: Robert Bunge <[e-mail]>
Subject: Vandalizing the sky.
Newsgroups: sci.astro,sci.space

In article <[e-mail]> [e-mail] (Josh Hopkins) writes:
>I'm wondering if "vandalize" is the proper word to use in this situation.  My
>dictionary defines "vandalism" as "the willful or malicious destructuion of
>public or private property, especially of anything beautiful or artisitc." I
>would agree the sky is beautiful, but not that it is public or private property.

It's public because it belongs to everybody.  It's vandalism because many people -- power companies -- do maliciously waste light.  If they can sell you
or your city or your state an unshielded light that wastes 30 to 50 percent
of its light, they make more _money_.  Never mind that your money is wasted.
Never mind that taxpaper's money is wasted.  Never mind that the sky is ruined.


Bob Bunge

Greed is Great - Gordon Grekko

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

Date: Fri, 30 Apr 1993 15:34:10 GMT
From: Henry Spencer <[e-mail]>
Subject: What planets are habitable
Newsgroups: sci.space

In article <1rpt1v$[e-mail]> [e-mail] (Ken Hayashida) writes:
>As for human tolerances, the best example of human endurance in terms
>of altitude (i.e. low atmospheric pressure and lower oxygen partial pressure)
>is in my opinion to the scaling of Mt. Everest without oxygen assistance...
>... This is quite a feat of physiological endurance...

Indeed so; it's at the extreme limit of what is humanly possible.  It is
possible only because Mount Everest is at a fairly low latitude:  there
is a slight equatorial bulge in the atmosphere -- beyond what is induced
by the Earth's rotation -- thanks to the overall circulation pattern of
the atmosphere (air cools at poles and descends, flowing back to equator
where it is warmed and rises), and this helps just enough to make Everest-
without-oxygen feasible.  Only just feasible, mind you:  the guys who did
it reported hallucinations and other indications of oxygen starvation,
and probably incurred some permanent brain damage.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

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End of Space Digest Volume 16 : Issue 509
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