Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V10_0/V10_013.TXT

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Subject: SPACE Digest V10 #13

SPACE Digest                                      Volume 10 : Issue 13

Today's Topics:
             Re: Voyager: Tape recorder?
             Re: Books about Space Flight
            Soviet lunar programme
               Re: Pluto fly-by
             launchers and launch delays
             Sunraster Voyager II images
             Re: Neptune on the Boobtube
          Voyager Pictures moved to another machine
         Re: Voyager Interstellar Trajectory
               Re: Face on Mars
----------------------------------------------------------------------

Date: 27 Aug 89 21:49:12 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Voyager: Tape recorder?

In article <[e-mail]> [e-mail] writes:
>I keep hearing of data being spooled to the tape recorder for later
>transmission to earth.  Surely they don't use a conventional mag.
>tape drive.  Wouldn't something solid state like a large array of
>eeprom be more robust?

They use a conventional -- well, specially-designed -- mag tape drive.
Remember that this thing was designed 15 years ago.  Also remember that
it had to survive a radiation dose that would have killed a human passenger,
during Jupiter encounter; I doubt that EEPROMs are rad-hard yet.

NASA has sponsored work on things like bubble-memory systems aimed at
replacing the magtape drives, which have been a reliability headache on
birds like the Landsats.  Don't know what the state of affairs is on that,
or what would be used in a bird designed today.
--
V7 /bin/mail source: 554 lines.|     Henry Spencer at U of Toronto Zoology
1989 X.400 specs: 2200+ pages. | uunet!attcan!utzoo!henry [e-mail]

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

Date: 27 Aug 89 15:05:20 GMT
From: mcsun!ukc!icdoc!syma![e-mail]  (Nick Watkins)
Subject: Re: Books about Space Flight

>
>Any other books that people would like to add?

As it happens, yes. I am interested in hearing suggestions of books that
have good critical examinations of manned Space Flight.

Three to get the ball rolling:

1) "If the Sun Dies" by Oriana Fallaci. An Italian journalists' dialogue
with herself and her father about the US programme c. 1965. One of the
best space books ever written, IMHO, but little known. I've only ever seen it
cited by Brian O'Leary & Joe Allen. She is a reluctant convert. Was she
the prototype for Michener's Cynthia Rhee? (in "Space").

2) "Space Colonies" edited by Stuart Brand. Much food for thought and no
definite answers.

3) "The Final Frontier" by Dale Carter (Verso,1988). A minority taste,
possibly, as it is ostensibly a work of lit. crit. based on Gravity's Rainbow
but contains much interesting material.

Any more?

Nick




--
Nick Watkins, Space & Plasma Physics Group, School of Mathematical
& Physical Sciences, Univ. of Sussex, Brighton, E.Sussex, BN1 9QH, ENGLAND
JANET: [e-mail]   BITNET: [e-mail]
Voice: [phone]

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

Date: 27 Aug 89 13:42:58 GMT
From: mcsun!ukc!icdoc!syma![e-mail]  (Nick Watkins)
Subject: Soviet lunar programme

In article <[e-mail]> [e-mail] (Nick
Watkins) writes:

>... Soviets were set to land a man on the moon in 1968 says Tass". But
>the death in 1968 of Korolev "hampered and retarded the Lunar
programme".

Sorry, should have been 1966 for Korolev (my mistake). Wonder what two
more years would have given us ...

> Flight International also has an item saying essentially same thing.
> If there has been "sloppy reporting" (Henry) then it seems to have been Tass.

Seems to  have been mine actually. "Flight" for 26th August (p.14) says Bykovsky
has confirmed USSR planned to send one man around moon in a Zond in '68,
before Apollo 8. He says, according to Flight, that he was chosen pilot.
 They also quote unofficial reports that Belyayev was on pad in Dec '68
when launch was scrubbed. Bykovsky claims his launch was scrubbed in
'66.
 Article (unsigned but space correspondent is Tim Furniss) seems to contradict
itself unless they mean a Zond flight planned for '68 was cancelled in
1966, which leaves one wondering what the unmanned Zonds were for.
 Mark you, they also think Neptune has a moon called Noreid [sic] (at
least it wasn't Noraid).
>Anyone with access to Tass bulletins care to post or precis the original?
Request repeated. It seems to be getting like Chinese Whispers.

--
Nick Watkins, Space & Plasma Physics Group, School of Mathematical
& Physical Sciences, Univ. of Sussex, Brighton, E.Sussex, BN1 9QH, ENGLAND
JANET: [e-mail]   BITNET: [e-mail]
Voice: [phone]

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

Date: 28 Aug 89 03:11:26 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Pluto fly-by

In article <[e-mail]> [e-mail] (Terry Hancock) writes:
>>Infinite -- we cannot reach Pluto with current technology without a Jupiter
>>flyby...
>>
>    1> Depends on what you mean by "current technology" -- Ion
>drives capable of doing this (with the appropriate power source),
>do exist and have undergone vacuum chamber testing...

I was using the NASA definition of "current technology", more or less.
There are several high-exhaust-velocity systems, ion propulsion being
one of them, that have been checked out well enough to have a high
probability of working the first time, if anyone can be convinced to
try them.

For a Pluto ion mission there is a power problem, unless you do all your
accelerating near the Sun or buy a Topaz reactor from those primitive
backward Soviets... :-)

>    It's probably true that the Sun can't be used for the
>traditional "gravity assist" maneuver, but there are three advantages
>I can think of to doing the Sun flyby maneuver...

Yes, as I sort of alluded to, Sun flybys can be useful in more modest
ways.  Unfortunately, they do have a tendency to add things like thermal
complications to an already annoying set of tradeoffs.

>... flying past the
>Sun in the appropriate orbit (your final trajectory is very
>sensitively dependent on your trajectory toward and away from the
>Sun.  Essentially this eliminates the need for Jupiter to be
>in the "right place" -- occasionally it will be in the "wrong
>place," but you clearly have more options this way.

I wouldn't have thought that the exit trajectory from a velocity-gain
Jupiter gravity-assist maneuver would pass close enough to the Sun to
be useful for this.  (Velocity-loss maneuvers like those for Ulysses
and Starprobe are another story, but you wouldn't use those for an
outer-planets mission.)  The velocity gain from Jupiter is necessarily
pointed more or less forward along Jupiter's orbit.
--
V7 /bin/mail source: 554 lines.|     Henry Spencer at U of Toronto Zoology
1989 X.400 specs: 2200+ pages. | uunet!attcan!utzoo!henry [e-mail]

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

Date: 28 Aug 89 03:18:46 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: launchers and launch delays

In article <[e-mail]> [e-mail] (Terry Hancock) writes:
>...before CRAF and Cassini get launched.  Fortunately they
>are not scheduled on a Shuttle flight (they'll be launched with
>expendable launch vehicles), and therefore probably won't be
>subject to long launch delays like Galileo was.

Ho ho.  Remember that if Galileo had been scheduled for Titan launch in
summer 1986, its real launch date might be exactly the one it's got now,
fall 1989.  Expendables fail just like the shuttle -- Titan did, for
example -- and one-of-a-kind probes don't fly on the first mission
after a major failure.  The result:  long launch delays.

The shuttle does lose, somewhat, on hitting short launch windows.
Magellan made it, and Galileo will *probably* make it, because NASA
has put an awful lot of effort into making sure of it, including
cancelling or postponing missions that might have gotten in the way.
Expendables have been known to miss windows too, but they're less prone
to it.
--
V7 /bin/mail source: 554 lines.|     Henry Spencer at U of Toronto Zoology
1989 X.400 specs: 2200+ pages. | uunet!attcan!utzoo!henry [e-mail]

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

Date: 28 Aug 89 02:38:55 GMT
From: unmvax!deimos.cis.ksu.edu!umrisca![e-mail]  (Doug Meyer)
Subject: Sunraster Voyager II images


umrisca.isc.umr.edu (131.151.8.1) has available (via anonymous ftp, in
file neptune.tar.Z) a sampling of Voyager images from Neptune.  These
images are the Sun rasterfile equivalent of the encapsulated postscript
images available from hanauma.stanford.edu (36.51.0.16). Thanks go to
Joe Dellinger and his MacII for grabbing them.

These should be displayable by any software capable of handling Sun
rasterfile format, such as xviewsun (in X-Windows) or touchup (for
Suntools).

IMPORTANT: Be sure to make note of ALL the disclaimers and copyrights
       in Joe's original README file (now README.2ND). They go for
       me too. Especially the one that says:
           ----------------------------------------
           THESE IMAGES ARE COPYRIGHTED BY NASA-JPL
           ----------------------------------------

Doug Meyer ([e-mail])
Intelligent Systems Center
University of Missouri-Rolla

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

Date: 28 Aug 89 00:17:05 GMT
From: jtsv16![e-mail]  (Brian A. Jarvis)
Subject: Re: Neptune on the Boobtube

In article <[e-mail]> [e-mail] (John Sparks) writes:
>In article <44600002@primerd> [e-mail] writes:
>>
>Well I watched it. Just who were the dweebs that they had commenting? For the
>most part they didn't know their head from their A**.
>
>At one point a caller asked what will happen to Voyager, where will it go when
>it leaves the system.
>
>The answer was that in 8,000 years it will fly by Barnard's Star, in 20,000 or
>so it will pass Proxima Centauri, and then the Oort cloud.

I was watching the Journal on CBC the other night; they were interviewing
a person from the University of Toronto on the Voyager fly-by.  The
interviewer asked what becomes of the probe after Neptune.  The interviewee
said eventually it would be dragged back into the solar system by the
sun's gravity and could conceivably fly by Earth again in a few centuries.

I wish I had noted who it was exactly that was being interviewed.  Must
have been a janitor, or something...

--
Brian A. Jarvis,                        J.T.S. Computer Systems,
"Ego as an Art!"                        Downsview, Ontario
...jtsv16!brian                         Canada M3H 5T5  [phone]
       A toast - "To our wives & sweethearts:  may they never meet!"

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

Date: 29 Aug 89 00:24:51 GMT
From: agate!shelby!portia!hanauma.stanford.edu![e-mail]  (Joe Dellinger)
Subject: Voyager Pictures moved to another machine


    Arg! I didn't know what I was letting myself in for on this one.
I posted on Sunday around noon, and got a steady stream of connections from
the US and Canada all afternoon. Then as Europe got up on their Monday
morning we started to get mostly connections from the UK, France, and the
Netherlands. No problem so far. But Monday morning! Yow! We got absolutely
inundated with anonymous ftp connections, all grabbing the Neptune pictures.
The ftp-load kept increasing and increasing, until it reached the point where
we had at least 10 ftpd processes running all the time.

    Needless to say, while I was thrilled to see how popular Voyager was,
the other users of the computer were NOT pleased with me. I was ordered to
pull the plug...

    But all is not lost! The Voyager pictures which were formerly
available on hanauma.stanford.edu are now available on

mazama.stanford.edu (IP address 36.51.0.8)
^^^^^^                                  ^

    The people who normally use this machine are on vacation, so
they aren't here to complain! Hah! To keep the Stanford Network people
from complaining, you might want to also limit your ftping to outside
normal work hours, Pacific Daylight Time (7 hours behind GMT).

    Since I'm getting a flood of questions "we tried to connect to
Hanauma but were refused, what are we doing wrong" please excuse me for
not answering such questions. I'm also going to have to stop answering
questions from people who want to plot the pictures but think it is
easier to send me mail asking about the format than reading the README
file provided.

    If you want me to actually MAIL you the pictures, you are going
to have to convince me you want them so much you will be permanently
emotionally scarred if you don't get them. :-) Alternatively, send me
a useful public-domain generic graphics utility subroutine for my collection.
I'm really busy these days, and this has turned out to be much more of a
time sink than I counted on already.

    I'll turn on Hanauma's anon ftp account again in a week or so,
once the floodwaters have receded. (Hanauma has some other nice things
available besides the Neptune pictures.)

    Share and Enjoy.
\    /\    /\    /\/\/\/\/\/\/\.-.-.-.-.......___________
 \  /  \  /  \  /Dept of Geophysics, Stanford University \/\/\.-.-....___
  \/    \/    \/Joe Dellinger [e-mail]  apple!hanauma!joe\/\.-._

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

Date: 28 Aug 89 17:01:53 GMT
From: tekbspa!optilink![e-mail]  (Clayton Cramer)
Subject: Re: Voyager Interstellar Trajectory

In article <[e-mail]>, [e-mail] (Terry Hancock) writes:
> >
# #The answer was that in 8,000 years it will fly by Barnard's Star, in 20,000 or
# #so it will pass Proxima Centauri, and then the Oort cloud.
# #
#     Okay, so this is completely wrong.  The announcer probably
# confused talk about how long the probe would take to get to those
# stars IF it were headed toward them.  As for the Oort cloud, well,
# they'll have to fend for themselves on that one.
#
# My QUESTION:
#     What is the outbound assymptotic trajectory of Voyager as it
# leaves the solar system?  By this, I mean which coordinates
# (Equatorial, Ecliptic, or Galactic) will it approach asymptotically
# as  viewed from Earth?
#
#     I heard that it would pass a nearby star within ~1 ly, which
# star is that? (clearly, the answer to the above will answer that
# question in itself).
#
# Terry Hancock

This is a subject near and dear to me.  I asked this question in
1975, when I was working on Voyager.  The scientist I asked said,
"I'll get back to you on it."  He never did.  Most recently, I
have read that the nearest star will be 28 Wolf, in around 40,000
years, and it will approach within a light year of it.

--
Clayton E. Cramer {pyramid,pixar,tekbspa}!optilink!cramer
William Bennett: The best argument yet against philosopher-kings.
----------------------------------------------------------------------------
Disclaimer?  You must be kidding!  No company would hold opinions like mine!

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

Date: 28 Aug 89 15:01:44 GMT
From: att!mtuxo![e-mail]  (54317-T.EBERSOLE)
Subject: Re: Face on Mars

In article <[e-mail]<, [e-mail] (James P. Galasyn) writes:
<
< I was not impressed by the abstract posted here awhile back.  A couple
< year ago, _Omni_ printed an article about the Face, full of beautiful
< computer-enhanced images of the thing, but I figured that it could be
< an accident if that's all there was:  a Face in the desert.  Also, it
< was _Omni_.
<
    etc.

< craters, a five-sided pyramid with the Golden Ratio built into it, and
< the Face.  The structure he identifies as "The City" has right angles in
< it, and if you stand in the "City Square" and look at the Face, the
<
The most telling clue of all: I've just seen an hour-long broadcast of
a show which included pictures of "The Face." Check out the rerun schedules.
The clue appears in the final credits for almost any episode of "the New
Mike Hammer." I figure this is at least as good a reference as has appeared
so far.

--
=============================================================================

Tim Ebersole ...!att!mtdcc!tee
         or ...!{allegra,ulysses,mtune,...}!mtuxo!mtdcc!tee

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

End of SPACE Digest V10 #13
*******************