Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v16_6/v16no642.txt

Internet Message Format | 1993-07-13 | 30KB

Date: Fri, 28 May 93 14:23:51
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #642
To: Space Digest Readers
Precedence: bulk


Space Digest                Fri, 28 May 93       Volume 16 : Issue 642

Today's Topics:
                   Another spectral class mnemonic
                  Detecting planets in other system
             Free seismology textbook on CD-ROM (2 msgs)
        Hey Ken! You awake? You exist? (LEO Cost; Return cost)
     How do I convert Galactic Longitude & Latitude to 3D system?
                    Kepler's dream of space travel
                        Launch Vehicle Permits
   Microlensing searches (was "detecting planets in other systems")
                            Minds in Space
                              Moon Base
                  Privatizing scientific terminology
                            Space Raffles?
           Tom Wolfe's THE RIGHT STUFF - Truth or Fiction?
Voyager Discovers the First Direct Evidence of the Heliopause (3 msgs)

    Welcome to the Space Digest!!  Please send your messages to
    "[e-mail]", and (un)subscription requests of the form
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----------------------------------------------------------------------

Date: 27 May 93 23:44:49 GMT
From: Tom Zych <[e-mail]>
Subject: Another spectral class mnemonic
Newsgroups: sci.space,sci.astro

Obviously Brainy Astronomer Finds Galaxies Keep Moving,
  Revealing New Science
--
Tom Zych
[e-mail]

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

Date: 28 May 1993 05:07:22 GMT
From: Joe Elso <[e-mail]>
Subject: Detecting planets in other system
Newsgroups: sci.space,sci.astro

In article <[e-mail]>, [e-mail] (Thomas Clarke) writes:

     > In a recent issue of Science there is a discussion of a project
     > to look for MACHOs (Massive Compact Halo Objects - things like
     > planets, brown dwarfs, or even black holes in the galactic halo
     > that might account for some of the missing mass).  The scheme for
     > detecting MACHOs is to look for a micro-gravitational lensing event
     > as the MACHO passes in front of a distant star.  To make the
     > statistics workable they have put together a 64 million (!!!) pixel
     > CCD which will be mounted on an otherwise little used 50-odd inch
     > worn-out telescope.  The CCD will then stare at the large Magellenic
     > Cloud (LMC) to look for microlensing events.  They expect a
     > jupiter-sized object to enhance a stares brightness for a day or two,
     > a week or two for dwarfs, and possibly months for a black hole.
     >

There is no "will" & "will be" about it - the MACHO project is going strong
right now.  They have analysed 10% of the data and found 1 probable event
& 2 possibles (plus 28,000 variables!!).  The data handling required is
mighty impressive - they take an exposure every 5 minutes, all night,
every night (weather etc permitting :-) ).

--

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Joe Elso                    CSLab, Research School of Physical Sci. & Eng.
[e-mail]        Australian National University (249 0446)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

          "No matter what your cause, it's a lost cause if we
           don't control human numbers"  - Paul Ehrlich

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

Date: 28 May 1993 05:46:50 GMT
From: Jon Claerbout <[e-mail]>
Subject: Free seismology textbook on CD-ROM
Newsgroups: sci.astro,sci.bio,sci.math,sci.math.stat,sci.med,sci.space,sci.engr,sci.physics,sci.geo.meteorology,sci.math.num-analysis,sci.engr.mech,sci.image.processing

Free seismology textbook on CD-ROM for UNIX computers with X11.

Includes two PhD theses and nifty electronic document software.
Does not work on PC, MS-DOS, or MacIntosh.
Many bugs fixed since our 1991 edition

Mail your request on your institutional letterhead to

    Jon Claerbout
    Geophysics Department
    Stanford University
    Stanford, CA 94305-2215
    USA

details below +-+-+-+-+-+-+-+-+-+-+-  =  +-+-+-+-+-+-+-+-+-+-+-



            Seismology on CD-ROM
    Disk SEP-CD-4 produced at Stanford University includes
\item
    ``Earth soundings analysis: processing versus inversion'', \\
    a {\bf textbook} by Jon F. Claerbout,
\item
    ``Imaging by the wavefront propagation method'', \\
    a doctoral {\bf dissertation} by Lin Zhang
\item
    ``Elastic modeling and migration'', \\
    a doctoral {\bf dissertation} by Carlos Cunha Filho
\item
    Documents and {\bf software}
    by students and former students at the Stanford Exploration
    Project (SEP)
    and software gleaned from the internet
    that enable you to build electronic documents,

You need a CD-ROM drive and a UNIX workstation with X11 and Fortran.
Our disk includes binaries for IBM RS-6000, Hewlett-Packard 700 series,
Sun 4 (not Solaris 2), and DEC 3100.


In many branches of engineering and science
there is a substantial computational element.
Seismology is one of these.
In taking up computational problems
we should abandon books, journals, and reports
and replace them with electronic documents
that can be used to recreate any print document,
including its figures,
from its underlying data and computations.
Today, few published results are reproducible in any practical sense.
To verify them requires almost as much effort
as it took to create them originally.
After a time,
authors are often unable to reproduce their own results!

It is time to plunge into a new era.
These electronic documents
contain everything needed to rebuild themselves;
data, programs, graphics libraries, text, and word processor.
This software,
gathered and prepared at the Stanford Exploration Project,
is presented in a way to encourage you to
prepare reproducible electronic documents.

{\bf Interactivity.}
Where a figure caption contains a pushbutton (word in a box),
you can press the button
to interact with the figure.
Most figure captions contain pushbuttons.
Some of these pushbuttons launch fun interactive programs.

{\bf Reproducibility.}
Each figure caption is followed by an [R] or an [NR] which
denotes Reproducible or Not Reproducible.
You can press a button to ``burn'' any reproducible figure,
and another to rebuild it according to your own specifications,
including any changes you may have made
to the parameters, programs, or data.


Some people see reproducibility of research as a troublesome ethical issue.
We see it as an everpresent, irritating practical concern.
We are annoyed when we cannot easily reproduce our own work.
Some of us are irritated when other professors publish
grandiloquent papers whose conclusions require too much time to confirm.
And we are further frustrated when new students cannot reproduce
(in a year) the work of other recently graduated students.
Although each student prepares a doctoral dissertation
that should enable others to reproduce that work,
the reality is that paper documents are outdated;
they no longer fulfill the role they did a generation ago
when data consisted of photographs and pencil marks
on a piece of paper---when theory was
several pages of Greek symbols.

Paper no longer serves us well.
Our data now resides in a computer,
and our theory is embodied in computer programs.
Many libraries overflow and they
cannot afford the materials they want.
At a million characters per book,
over 600 books could be on a CD-ROM with
a retail cost below 2 cents per book.
We do not have 600 books
so we filled our CD-ROM
with the accumulated shared software library
of many current and former students.
We added many valuable, publicly available programs
including fortran extenders and programs
for composition and typesetting.
We added seismograms.
And, most importantly, we glued it together with
``shell scripts'' and ``makefiles''
that enable us and others to reproduce all our work.
We call this a ``{\bf living document}.''

Our experience shows that it is only slightly more difficult to give birth
to a ``living'' document than a ``dead'' one.
The major hurdles in preparing
a doctoral dissertation, research monograph or textbook
are these:
(1) mastering the subject matter itself,
(2) writing the ancillary technical programs,
(3) using a text editor and word processing system,
and (4) writing the command scripts
that run the programs to make the illustrations.
The difference between preparing a ``live'' document and a ``dead'' one,
lies in the command scripts.
Will they be run once and then forgotten,
or will they be attached to the figure-caption pushbutton?
Authors who wish to communicate will produce live documents.
Authors who merely wish to advertise their scholarship
without really sharing it will continue to produce dead ones.
The increase in effort for the authors is minuscule---once
they learn how to organize their work properly
and to ``file'' it electronically.

When you look beneath the surface of these documents
you will find everything you need to make your own living documents.
And you can freely copy it from our disk.
At the beginning of the computer revolution,
I gave young students the advice: ``Learn how to type.''
With the mass-storage revolution now underway,
and with a \$10 CD-ROM able to hold all the keystrokes
you can type in a lifetime,
I now advise everyone: ``Learn how to file.''

Jon F. Claerbout and Martin Karrenbach

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

Date: Fri, 28 May 1993 07:37:44 GMT
From: Jack Sarfatti <[e-mail]>
Subject: Free seismology textbook on CD-ROM
Newsgroups: sci.astro,sci.bio,sci.math,sci.math.stat,sci.med,sci.space,sci.engr,sci.physics,sci.geo.meteorology,sci.math.num-analysis,sci.engr.mech,sci.image.processing

Indeed you are correct. Right now I am using authorware to make a simple
introductory physics course with calculus suitable for bright high school,
community college, US Navy PACE, and first year college levels. It's
a lot of fun. I am using Feynman's Lectures on Physics as my guide. But
there will be plenty of problems for students to work on interactively.
I am also using MATH CAD 4.0 and I have MATHEMATICA if I need it. I also
will be using 3D modeling program and Corel Draw. I am making rapid
progress and should be quite expert and efficient in a few months.

It's all straight stuff - non of my "crazy" ideas on faster than light
and backward in time quantum connection communication computing and
telepathic consciousness etc in this. That will be in my CD ROM
edition of my old best selling book SPACETIME AND BEYOND.

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

Date: 28 May 93 03:56:21 GMT
From: Lynne K Wahl <[e-mail]>
Subject: Hey Ken! You awake? You exist? (LEO Cost; Return cost)
Newsgroups: sci.space

[a whole bunch of stuff deleted]

>Exactly!  Not vehicles -- *payload*!  The vehicle *is not* payload.

>------------------------------------------------------------------------------
>[e-mail] - I don't speak for others and they don't speak for me.

Well, there is a minor technical point. The vehicle delivered to orbit
has portions that are not payload, but are still "usefull".  The shuttle
has the External Tank, and the Saturn has the (second? third?) stage.
Both of these are capable of being adapted with airlocks into *BIG* living
quarters (AKA Skylab) or melted down and re-manufactured in orbit like a
deposit can. (wonder what the deposit would be :)  There are some problems
that would have to be overcome like draining propellents, drilling the
airlock holes, and tacking the outside insulation down (on the ET).

--
--Lynn Wahl   [e-mail]           | The meek will inherit the
Kansas State University Student                | earth, the rest of us are
Soil Conservation Service Computer Specialist  | going to the stars. ----*

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

Date: 28 May 93 05:28:05 GMT
From: Morgoth the Mad <[e-mail]>
Subject: How do I convert Galactic Longitude & Latitude to 3D system?
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Mike Capron) writes:
>
> I am starting a science fiction FRP campaign and would like to generate star
> maps from actual stars in the galaxy.
>
> I have David Mar's starmapping program which generates maps from a
> 3 dimensional coordinate system.  I also have the Yale Bright Star
> Catalog (and a bunch of similar things) from around the net.  I thought
> this would be sufficient; I appear to have been wrong.
>
> The problem is that the star catalogs all seem to give star position in
> terms of two angles.  Galactic Latitude is the number of degrees north
> of the Galactic Equator (90 to 0 to -90) and Galactic Longitude is the
> number of degrees east along the disk made by the equator (although I'm
> not sure where 0 degrees is).  The catalogs also have right ascention and
> declination, which is a similar system, but centered on the Earth.
>
> Don't the intersection of these two angles leave you with a line?  Don't
> you also need to know distance from the center to convert to a 3D coordinate
> system?  Am I misreading the catalogs?  Help!
>
> Thanks in advance,
> Mike Capron
> [e-mail]
>
>
> PS: If I successfully create a conversion program, I will submit it to the
> FRP archives.

Can anyone on this sub email him and help??
I know its a gaming question (god forbid), but it is a legitamate question for
sci.space!??

==
Michael Adams, [e-mail] -- I'm not high, just jacked

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

Date: Wed, 26 May 1993 17:59:16 GMT
From: George Bendo <[e-mail]>
Subject: Kepler's dream of space travel
Newsgroups: sci.physics,sci.space

In article <[e-mail]> [e-mail] (John C. Baez) writes:
>I will describe it more when I have read it all, but for now I just
>CAN'T resist giving you all this little puzzle.  To WHOM did Kepler
>write a letter in 1610 saying:
>
>Who would have believed that a huge ocean could be crossed more
>peacefully and safely than the narrow expanse of the Adriatic, the Baltic
>Sea or the English Channel?  Provide ship or sails adapted to the
>heavenly breezes, and there will be some who will not fear even that
>void.... So, for those who come shortly to establish this journey, let
>us establish the astronomy....
>
Is the answer Galileo?  I understand that Kepler and Galileo did write
frequently to each other about each other's research

George Bendo






--
| George Bendo    | "The best laid schemes o' mice an' men                   |
| New Mexico Tech |                      Gang aft a-gley."                   |
| [e-mail]   |               - Robert Burns, "To a Mouse"               |

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

Date: 27 May 93 21:30:45 GMT
From: Mark Johnson <[e-mail]>
Subject: Launch Vehicle Permits
Newsgroups: sci.space

[e-mail] (Henry Spencer) writes:

>Transportation, which is part of the Dept. of Transport.  I'm told
>they can be reached at [phone], although I haven't tried myself.

>Anything that is capable of going above 100km needs an OCST permit.  Below
>that, I think they bow out and it's mostly the FAA that has to be kept happy.
>(The OCST minima are stated in more complex terms, but 100km is what they
>boil down to, I'm told.)

Actually, the criteria are even worse; OCST has jurisdiction over anything
with a thrust time > 15 seconds. Yup, this means that the high power non-
professional rocket guys had to get a waiver from OCST for this summer's
LDRS rocket launch, here in Kansas. :-(
--
Mark Johnson                          USnail: NCR Peripheral Products Division
E-mail:  [e-mail]       3718 N. Rock Rd.
Voice: [phone] [V+ 654-8189]           Wichita, KS  67226
[Non-business email: [e-mail]]

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

Date: Thu, 27 May 1993 15:49:56 GMT
From: Stupendous Man <[e-mail]>
Subject: Microlensing searches (was "detecting planets in other systems")
Newsgroups: sci.space,sci.astro

In article <[e-mail]> Leigh Palmer <[e-mail]> writes:
>In article <[e-mail]> Thomas Clarke,

  Thomas Clarke, talking of the MACHO project (who are looking for
microlensing events by staring at the Magellanic Clouds), says

> The point, of this is that maybe the same detector will inadvertantly
> succeed in detecting planets.  It would be ironic if the first
> detection of a Jupiter-sized planet were in the LMC!

  Actually, in order to produce a microlensing event, I believe
that a Jupiter-sized lensing object would have to be in the halo of our own
galaxy, not in the LMC itself.  I don't think that the MACHO search is
sensitive enough to detect the millimag variation caused by a
planetary occultation, as we've been discussing lately.

  Leigh Palmer says

>If I had a machine like that I'd point it into the center of the Galaxy.

  Which is exactly what the OGLE group is doing.  The OGLE (Optical
Gravitation Lensing Experiment) project is similar to the MACHO search,
in that it is designed to detect gravitation microlensing (for details,
read the article by Udalski et al., Acta Astronomica, 42, 253 (1992)).
Instead of looking at the LMC as a source of stars-to-be-lensed, however,
the OGLE group is looking at the bulge of our own galaxy.  They hope to
see microlensing events due to foreground objects in and near
the disk of our galaxy passing in front of more distant bulge stars.
The OGLE group consists of a contingent from Warsaw University,
and the Carnegie Institute; they are using the 1-meter Swope telescope
at Las Campanas with a 2048x2048 CCD, so their data acquisition rate is
quite a bit smaller than the MACHO group's.  They work in I and V,
allocating most of the time to I. Last year, they got about
50 good nights, from April through August 1992.

  The number of stars with photometric errors < 0.1 mag detected
were (adding up all the stars in different fields) about 150,000!
As Leigh mentioned, they find MANY variable stars; Bohdan Paczynski,
who's been following the project very closely, has a big poster on
his door which shows about 50 beautiful light curves of various
types of variable stars, which is, of course, a tiny fraction of the
total number.  So far, no microlensing events, but the total amount
of information one COULD find in the database is enormous.

  The MACHO project will tell us a heck of a lot about the properties of
the LMC (including distance), and the OGLE project a heck of a lot about
the bulge and disk of our own galaxy.  But it's going to take years for
people to sort through all the data and pick out the useful bits.
Graduate students who are looking for thesis topics, take note!

--
-----                                                    Michael Richmond
"This is the heart that broke my finger."    [e-mail]

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

Date: 28 May 1993 08:04:29 GMT
From: Diaspar Virtual Reality Network <[e-mail]>
Subject: Minds in Space
Newsgroups: sci.space

June 23, 1993 Event called "Minds in Space"

The Diaspar Virtual reality Network, Verde Software and the
Electronic Cafe in Santa Monica, California will be sponsoring an e
an event on June 23, 1993 called "Minds in Space" from 7:30 pm
to 9:30 pm.

The content and nubmer of people presenting information about
space is still "up in the air" <grin> and undergoing planning.

Thislooks like it should be a worthwhilke event to attend.

And, if you have something worthwhile to say and can do it
effectively in person in 5 to 10 minutes, let me know and I
will see if it can be included. My goal is for many people
to share info about space.

There will probably be video-phone links to Phoenix and to
Albuquerque so that some presenters will share their information
wit hthe main group in Santa Monica.

As I know more I will post it. And, as a side note, I will
get those DC-X stereoscopic .gifs done soon. I have had zero
time and just got back from speaking at the Meckler VR con-
ference. All who emailed me have not been forgotten. And,
we will get those .gifs up on an ftp site as soon as they are
ready.

So, in summary:

1. Minds in Space on June 23, 1993 (7:30 pm to 9:30 pm)
2. If you wish to be a part of this., let me know.
   (we could even use some to transcribe info for the nets,
     there will be live connection to Diaspar that evening,
      which is tel-netable)
3. I will get those steroscopic .gifs out soon.

David Mitchell
Diaspar

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

Date: Fri, 28 May 1993 03:44:36 GMT
From: Henry Spencer <[e-mail]>
Subject: Moon Base
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Tom Zych) writes:
>However, I did have the impression that moonquakes are fairly
>common.  Anyone know if this is true? ...

I think you've been reading pre-Apollo science fiction. :-)  The Moon is
amazingly quiet seismically.  It's just completely dead.  The seismic
background is so low that before the Apollo seismometer network was
shut down, the folks running it claimed to be able to hear the impact
of a basketball-sized meteorite anywhere on the Moon.  (In fact, as a
seismic network it was a bit of a bust after Apollo stopped slamming
rocket stages into the Moon; there just wasn't much internal to
hear.  But it made a dandy large-meteorite detector, with a collecting
area 3000km across.)
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

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

Date: 28 May 1993 00:12:46 GMT
From: Pawel Moskalik <[e-mail]>
Subject: Privatizing scientific terminology
Newsgroups: sci.space,sci.astro

   Isn't it enough that we already have "Toyota Profesor of Physics" ???


This is no joke, I have met a scientist with such title .....



Pawel Moskalik

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

Date: Fri, 28 May 1993 03:53:26 GMT
From: Henry Spencer <[e-mail]>
Subject: Space Raffles?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (David B. Lapadula) writes:
>I think I recall reading/hearing about some sort of Soviet venture where they
>tried to sell raffle tickets, with the lucky winner getting to go to MIR, or
>something like that. I recall that it was done w/a US partner.
>
>Did the whole thing turn out to be a sham? Misunderstanding between the
>Soviets (Russians?) and the US partners? Or what?

There were some (brief) misunderstandings along the way.  But it was a
completely legitimate project:  some US entrepreneurs set it up, and
got a signed-and-sealed contract with Glavkosmos to supply the launch.
Much of the financing was to come from sponsorship, actually, not from
the ticket sales.

Then somebody in the local DA's office who hadn't read the fine print
jumped to conclusions and decided it was illegal (it wasn't), and by
the time he figured out his mistake, he was in too deep to back out.
If they'd been big and well-financed, they could have survived the
legal harassment, but they weren't.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

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

Date: 28 May 1993 00:10:55 GMT
From: Claudio Oliveira Egalon <[e-mail]>
Subject: Tom Wolfe's THE RIGHT STUFF - Truth or Fiction?
Newsgroups: sci.space,sci.space.shuttle,rec.arts.books

Kennith Johnson writes

> Let me ask you this.  If you were writing a book about your
> experiences as the wife of Gus Grissom, would YOU mention the
> fact that you might have considered slashing your wrists?  I
> wouldn't.

Neither me... By the way do you know any other reference that
would confirm or not what Tom Wolfe had written in his book
about  the above incident? The point that I was trying to make
was whether  Tom Wolfe had described the incident accurately
or not after all, the original question was whether the THE
RIGHT STUFF  was Truth or Fiction...

> Why does it matter so much whether or not Gus (it's spelled with
> one 's', by the way) Grissom (with an 'm') was surprised at the way
> his wife reacted?

It matters so much because if he did not describe this incident
accurately, he might had carried out other inaccuracies to other
parts of his book.

BTW thank you for correcting my spelling.

[e-mail]

Claudio Oliveira Egalon

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

Date: 27 May 1993 20:12:40 -0700
From: Julie Bixby <[e-mail]>
Subject: Voyager Discovers the First Direct Evidence of the Heliopause
Newsgroups: sci.space,sci.astro,alt.sci.planetary

I'm confused. I though one of the Pioneer probes had already discovered
the heliopause a few years ago.

--
Julie Bixby                        Internet: [e-mail]
Engage Romulan .sig cloaking device....

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

Date: 28 May 93 04:34:13 GMT
From: Jeff Bulf <[e-mail]>
Subject: Voyager Discovers the First Direct Evidence of the Heliopause
Newsgroups: sci.space,sci.astro,alt.sci.planetary

In article <1u3vv8$[e-mail]>, [e-mail] (Julie Bixby) writes:
|> I'm confused. I though one of the Pioneer probes had already discovered
|> the heliopause a few years ago.

I'm sure somebody who is still at NASA can answer this better than I,
but here goes anyway...

Pioneers 10 & 11 did go beyond Pluto first and are still on their way
out there looking for that heliopause. But each of the four
spacecraft (2 poineers and 2 voyagers) is headed in a different
direction. I believe one of the Voyagers is on the trajectory nearest
the close part of the heliopause.

What you remember is probably a NASA puff piece (excuse me: press release)
about Pioneer being on its way to find the heliopause.
True, but not the same thing.

More detatiled info from Ames or JPL would certainly be welcome.
--

___  __|    __ \
    |      |    |    dr memory
    |      |   /    [e-mail]
    |       ___ \
    |      |     |    Pluto? Gawrsh, Mickey!
____|     ______/

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

Date: Fri, 28 May 1993 05:12:32 GMT
From: Tim Schneider <[e-mail]>
Subject: Voyager Discovers the First Direct Evidence of the Heliopause
Newsgroups: sci.space,sci.astro,alt.sci.planetary

In article <[e-mail]> [e-mail] (Ron Baalke) writes:
>Paula Cleggett-Haleim
>Headquarters, Washington, D.C.                        May 26, 1993
>(Phone:  [phone])
>
>Mary A. Hardin
>Jet Propulsion Laboratory, Pasadena, Calif.
>(Phone:  [phone])
>
>RELEASE:  93-099
>
>VOYAGER SPACECRAFT FIND CLUE TO ANOTHER SOLAR SYSTEM MYSTERY
>
>   ... STUFF DELETED ...

>watts.  However, these radio signals are at such low frequencies,
>only 2 to 3 kilohertz, that they can't be detected from Earth."

This is very interesting stuff.  However this point is somewhat unclear
to me.  Could someone please elucidate?

>   ... MORE STUFF DELETED ... Ron Baalke         | [e-mail]


Thanks in advance...     Timothy Schneider
            [e-mail]

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


From: Tom Zych <[e-mail]>
Newsgroups: sci.space
Subject: Re: Moon Base
Summary: Lunar observatories
Message-Id: <[e-mail]>
Date: 27 May 93 23:12:01 GMT
References: <[e-mail]> <[e-mail]> <stephens.738348906@ngis>
Sender: "Tom Zych"@hertz.njit.edu
Organization: New Jersey Institute of Technology, Newark, N.J.
Lines: 29
Nntp-Posting-Host: hertz.njit.edu
Source-Info:  Sender is really [e-mail]
Source-Info:  Sender is really [e-mail]

In article <stephens.738348906@ngis> [e-mail] (Dave Stephenson) writes:
>[e-mail] (Gary Coffman) writes:
>>[Summary: Farside radio observatory for shielding from Earth's noise;
>>Optical observatory no good due to mining & blasting.]

>Wrong about optical observatories. Optical interferometers could be built
>on the Moon, as it is a stable structure to optical wavelenght dimensions.
>An array of interferometric telescopes on the Moon could image Earth-like
>planets around near-by stars. This could not be done on the moving plates
>of the Earth, or in space.

Mining and blasting would not be a problem as long as such operations
were confined to areas more than a few hundred miles away, I think.
I haven't heard of astronomers here having problems with it, or am I
simply displaying my ignorance?

However, I did have the impression that moonquakes are fairly
common.  Anyone know if this is true?  This would render any
blasting insignificant.

The shielding argument would also apply, I suspect, to another set
of wavelengths.  IR imaging devices would be more easily kept cool
on the moon than in open space; use them during the dark semi-lunar,
and keep the liquid He underground during the bright.  Probably
simpler than whatever insulation IRAS used against the constant
solar heat.
--
Tom Zych
[e-mail]

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

End of Space Digest Volume 16 : Issue 642
------------------------------