Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V10_0/V10_062.TXT

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Subject: SPACE Digest V10 #62

SPACE Digest                                      Volume 10 : Issue 62

Today's Topics:
         Re: Voyager Interstellar Trajectory
              Re: RTGs for use on earth
         Voyager and Viking images on CD-ROM for $9!
   Re: Soviet's Soyuz TM-8 successfully docks to Mir space station
            Re: Linguistic Tidbits
              NASA and Face Data
               Mars Mission ship design
         Re: Economies of Scale in Launchers
----------------------------------------------------------------------

Date: 8 Sep 89 23:24:54 GMT
From: mailrus!jarvis.csri.toronto.edu!csri.toronto.edu![e-mail]  (Wayne Hayes)
Subject: Re: Voyager Interstellar Trajectory

[I've been having trouble posting, and I don't think this got through. ]

There's been alot of talk about Voyager 2's interstellar trajectory. The
following is from the July / August 1989 Planetary Report:

                                                        Voyager's Distance
Year    Comment                                         from Earth (light yrs)
---------------------------------------------------------------------------
2000    Enters Heliosheath
2012    Crosses Heliopause into interstellar medium
8571    Closest approach to Barnard's Star, 4.03 ly        0.42
20319    CA (Closest Approach) to Proxima Centauri, 3.21 ly    1.00
20629    CA to Alpha Centauri, 3.47                1.02
23274    CA to Lalande 21185, 4.65 ly                1.15
26262    Voyager 2 *enters* [sic] the Oort cloud        20,000 A.U (not ly)
28635    Voyager 2 exits Oort cloud            200,000 A.U

(long, long time passes)

129084    CA to Ross 154, 5.74 ly                    6.39
296036    CA to Sirius, 4.32 ly                    14.64
442385    CA to 44 Ophiuchi, 6.72 ly                21.88
957963    CA to DM+27 1311, 6.62 ly                47.38



Now this is just my subjective opinion, but the first set I wouldn't even
count as anything remotely interesting, since all those "closest approaches"
occur when the spacecraft hasn't even passed the Oort cloud, and is still
much closer to our Sun. Even if it was still functioning, it couldn't possibly
give us a better view than Earth or Earth-orbit views.

    Anyway, there it is.
--
Don't forget: 600 times the daily oral human intake of Sacharin injected
directly into the bloodstream of a lab rat might cause it bladder cancer.
Wayne Hayes    INTERNET: [e-mail]    CompuServe: 72401,3525

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

Date: 9 Sep 89 20:19:47 GMT
From: calvin![e-mail]  (John Sahr)
Subject: Re: RTGs for use on earth

In article <[e-mail]> [e-mail] (Neal Woodall) writes:

>In Brazil there was a similar incident last year. A radiation machine was
>stoler from a hospital, and wound up in a junk yard. The owner and his
>nephew busted the machine open while stripping it for scrap, and discovered
>this pretty glowing powder (uh oh!). Since they were all ignorant of most
>science (about zero education), they actually had a party where all of their
>friends came over an rubbed the glowing powder over their bodies! A few

It is a little unfair to blame these people for not knowing about highly
radioactive materials.  It is, after all, rather outside their usual
experience.  The only reason this didn't happen in the States
is that the irradiator would probably have been correctly disposed of.

(probably)

-john

(my opinions alone)--
John Sahr,     Dept. of Electrical Eng., Cornell University, Ithaca, NY 14853
johns@{alfven,calvin}.ee.cornell.edu,  {rochester,cmcl2}!cornell!calvin!johns
--When the dust settles, each B2 bomber will fund NSF for more than a year--

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

Date: 9 Sep 89 22:36:42 GMT
From: uakari.primate.wisc.edu!aplcen!haven!adm!nlm-mcs![e-mail]  (Michael D'Alessandro)
Subject: Voyager and Viking images on CD-ROM for $9!

TITLE:  New CD-ROM Holds Images from Voyager, Viking Missions

Here's good news for astronomy buffs and galaxy gazers.
Meridien Data, maker of CD-ROM premastering systems, is
offering a disc that holds hundreds of images sent back to
Earth by the Voyager and Viking planetary probes. The $9 disc
contains images that can be viewed on either an IBM PC or a
Macintosh.

However, the CD does not include recently photographed images
of Neptune, which Voyager 2 passed on its way out of the solar
system. The public-domain images on the disc are from Voyager
and Viking missions during the past 10 to 15 years, said
Meridien spokesperson Lou Hoffman. That includes images of Mars
(from the Viking probes of the late 1970s), Jupiter, Saturn,
and hundreds of other shots taken by the Voyager spacecraft.

The Voyager/Viking CD is called the GRIPS (Government Raster
Image Processing Software and Data) disc. Several government
agencies, including NASA, the Jet Propulsion Laboratory, and
the National Center for Supercomputing Applications,
contributed information for the disc.

Some of the images on the disc require up to 1.2 megabytes of
storage space, Hoffman said, but those aren't even close to
being the largest sent back from space. Some of the Voyager
images have been as large as 20 to 30 megabytes.

The GRIPS disc holds one set of data files that is shared by
both PC and Macintosh platforms. The disc adheres to the ISO
9660 file format; Meridien claims it's the first CD-ROM of that
format that both PC and Mac users can access.

No documentation comes with the GRIPS CD, and Meridien admits
it's not easy to locate a specific image from among the
hundreds on the platter. "There's a front-end index on the
disc, but it's difficult to use at this point," Hoffman said.
The company is working on a way to make the disc more "user
friendly," he added.

Meridien says the first pressing, of 1000 discs, is going fast
and that a second pressing of another 1000 could start in about
two weeks. "Response has been greater than we expected,"
Hoffman told Microbytes Daily. In fact, the company is
considering marketing a series of CD-ROM discs with images from
Voyager missions.

                            --- Jeffrey Bertolucci



Contact: Meridien Data, 5615 Scotts Valley Dr, Scotts Valley,
CA 95066; [phone]; fax [phone]



s is*** REPLACE THIS LINE WITH YOUR MESSAGE ***
--
Michael D'Alessandro
The National Library of Medicine
Lister Hill National Center for Biomedical Communications
Educational Technology Branch            Internet:  [e-mail]

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

Date: 9 Sep 89 18:39:16 GMT
From: mailrus!csd4.csd.uwm.edu!cs.utexas.edu!halley![e-mail]  (David M VomLehn)
Subject: Re: Soviet's Soyuz TM-8 successfully docks to Mir space station

In article <[e-mail]> [e-mail] (Glenn Chapman) writes:
>It was stated on shortwave that this crew might set a new record for
>man tended space experiments with the two expansion modules being added.
>...                      The other is planed for Feb. '90 and contains a
>special docking port which they expect to use with the Buran shuttle in 1991.

I think I remember some kind of treaty or agreement being signed shortly before
or after the Apollo-Soyuz mission in the 70's which specified a common docking
port for US and Soviet spacecraft.  This was to allow for the possibility of
space rescues, I think.  Two questions:

1)  Is my memory correct?

2)  Is the Buran docking port incompatible with this standard and, if so, what
    reasons have been given for the change?
----
David M. VomLehn                    work: [phone]
...utexas!halley!vomlehn                home: [phone]

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

Date: 12 Sep 89 21:31:38 GMT
From: concertina![e-mail]  (Steve Hix)
Subject: Re: Linguistic Tidbits

In article <[e-mail]>, [e-mail] (Jonathan McDowell) writes:
> From article <[e-mail]>, by [e-mail] (Steve Willner):
> [Farthest and closest points to the primary in an orbit...]
> > The generic terms are apoapsis and periapsis.  The plural, in case you
> > want to speak of both, is "apsides."  (Pronounced with three syllables:
> > aps'-uh-deez.)
>
> Steve points out that we should use Greek roots:
> > By the way, the apsides of lunar orbit are the "aposelene" and
> > "periselene;"

I've seen it fairly often (for such discussions, at least) as
perilune and apolune.

> I thought it was "pericynthion" and "apocynthion"?

I've seen *this* applied to Venus (modulo correct spelling, perhaps
as "pericynthian"?).  Dictionary says it should attach to the moon,
but "periaphroditial" gets to be a mouthful...  :}

> How about the rest of the solar system? I think that it's
> Mercury:    perihermes    aphermes
> Venus:        ?
> Mars:        periares    apoares
> Jupiter:    perizenon?
> Saturn:    perikronon?


------------
"...I was to learn later in life that we tend to meet any new situation by
reorganizing: and a wonderful method it can be for creating the illusion
of progress, while producing confusion, inefficiency and demoralization."
    - Petronius Arbiter, 210 B.C.

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

Date: 8 Sep 89 09:28:08 GMT
From: oliveb!amdahl!drivax![e-mail]  (MacLeod)
Subject: NASA and Face Data

George William Herbert writes:

:In article <[e-mail]> [e-mail] (Henry Melton) writes:
:>Book Review:
:>    The Monuments of Mars
:>    A City on the Edge of Forever
:>    by Richard C. Hoagland
:>    $14.95 North Atlantic Books  ISBN 0-938190-78-4
:>
:>This is a flawed book.  It is one of those irritating cases when the
:>author _delivers_ in the first few chapters, and then _blows_ it in the
:>later chapters when he doesn't know when to quit.
:
:>My recommendation to NASA:  Dedicate some imaging time of the Mars
:>Orbiter to these interesting landforms.  A very few high resolution
:>frames would go a long way.
:
:***Warning: Bloody Upset Person Posting***

:NASA already has better photos of the area.  Many were taken with
:different sun angles.  They basically show the face to be
:nonsymmetrical...oh well, there goes the neat idea.

:NASA _HAS NOT_ publicized this!

Have you seen such images (not photographs)?  If not, perhaps they only told
this to >their< true believers who acccept anything the priesthood asserts.

:After Hoagland published, NASA looked into it.  They enhanced, and looked at
:other images, and the result was that they disproved it.  They quietly told
:all the other astronomy and space science people.

Why quietly?  Damage control?  What will be your response if the next
Mars probe has "transmission problems" every time it's in the general
area of the Face?

:Result of NASA's failure to publish this (negative proof) data: Public
:believes in face.

There are the intransigent on each side of the issue, and a large group in the
middle.  I think the real "public" out there is unaware of the Face's
existence, or non-existence.

:I sat in on meeting two years ago, organized by UCB SPACE club.  Hoagland and
:some astronomy types duked it out.

:Astronomy types dismissed the theory, and attacked H. as pseudoscientific.
:Now, this may be true, but some of us in the audience hadn't seen the
:background that disproved the theory. Result: Scientists come out looking like:bufoons.

How does this follow?  Why were the scientists unable to provide contrary
proof?  I don't think that three low-res images prove much of anything, and
I'm dubious about Hoaglund's 3D modeling exercise, but it hardly seems like
there is enough evidence for any decision whatever.  But that will not
stop the fanatics on both sides from crowing about their respective positions.

:The lack of publication of this data has been one of the worst failures in
:modern science.  And it's all attributable to the scientists.

Come now.  How so?  Are there no political circumstances involved - like
interest in funding for future Mars probes?  Or in squelching planetary
missions in favor of the space station?  Or moon bases?

:Moral: Publicize Negative Findings!  ***upset dying down***

Well, Carl Sagan was paid dollars50,000 to not find anything; I guess we can
pack up and go home.  If a planetary scientist like Sagan doesn't find
formations like the Face and the City worth more study, what does he consider
interesting?

Sagan is an entertainer and political advocate and probably a designated
leaker for those who do know what's going on - whatever that is.  I have
a bad feeling that we aren't aware of the whole story, but that may be my own
paranoia speaking.


Michael Sloan MacLeod   (amdahl!drivax!macleod)

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

Date: 8 Sep 89 02:39:38 GMT
From: datapg!com50!questar![e-mail]  (Al Viall)
Subject: Mars Mission ship design


Setting aside long discussions on logistics of a Mission to Mars (cross your
fingers NOW), I would really like varied input on what you might think the
ship for a Mars Mission would look like and how it would operate.(you may now uncross your fingers)<---heh!!

Let's us possibly assume that the world powers could get together long enough
for such an undertaking, since we all know that such a project will take much
more than just one entity to do this.

Such a ship would most likely be designed to incorporate some sort of artificial
gravity for the two-year journey there and two-years back. But details,
lets hear details..........


--
  | Albert Viall                     |   EMAIL:[e-mail] |
  | ARPA: [e-mail]  |   FIDONET: 1:242/2                |
  |   "Uhh, Excuse me while I take a moment to adjust my tribble."       |
  ------------------------------------------------------------------------

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

Date: 7 Sep 89 14:57:31 GMT
From: swrinde!cs.utexas.edu!hellgate.utah.edu!wasatch!uplherc!esunix!bambam![e-mail]  (Bob Pendleton)
Subject: Re: Economies of Scale in Launchers

From article <[e-mail]>, by [e-mail] (Henry Spencer):
> In article <[e-mail]> [e-mail] (Bob Pendleton) writes:
>>> Are we confusing high thrust with efficiency?
>>
>>Could be. I don't claim to be an expert...
>>As I remember it, I don't have the articles with me, The effective
>>back pressure is lower for a high molecular weight exhaust.
>
> I had cause to review this recently for the talk I gave on Earth-to-orbit
> propulsion at the BIS party at the Worldcon.


I think it more likely that I missunderstood both what I read and what I
was told.

Can anyone tell me if there is a relationship between mass flow rate
and optimal nozzle skirt length? A relationship that is independent of
back pressure.

            Bob P.

P.S.

So, Henry, when are you going to post the text of your talk at the BIS
bash in Boston?

--
              Bob Pendleton, speaking only for myself.
UUCP Address:  decwrl!esunix!bpendlet or utah-cs!esunix!bpendlet

           Reality is stanger than most people can imagine

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

End of SPACE Digest V10 #62
*******************