Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v12_5/v12_501.txt

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Subject: SPACE Digest V12 #501

SPACE Digest                                     Volume 12 : Issue 501

Today's Topics:
            Re: Magellan Update - 10/24/90
           Re: "NAVY WITHHOLDING EVIDENCE"
               Re: photos from Voyager
           Re: space news from Sept 3 AW&ST
           Re: NAVY WITHOLDING EVIDENCE!!!
            Re: Pioneer 11 article
             Re: Theory for Life
             Re: Theories needed on life
              Galileo Update - 10/26/90
                LLNL Proposal
                 test

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

Date: 26 Oct 90 23:12:27 GMT
From: maytag!watcsc![e-mail]  (Trevor Green)
Subject: Re: Magellan Update - 10/24/90

[e-mail] (Robert McGwier) writes:
>[e-mail] (Ron Baalke):
>>
>>                       October 24, 1990
>> The Sun-earth-Magellan angle is now 2.5 degrees.
>
>Am I wrong in assuming that since we are near superior conjunction that
>you meant Earth-Sun-Magellan.

He meant what he said.  Doing some quick back-of-the-envelope
triangulation, the Earth-Sun-Magellan angle is about 174 degrees and
the Sun-Magellan-Earth angle is about 3.5 degrees.  This approximation
was done assuming the Titius-Bode approximation and ignoring the
triangle inequality as well as gravitic distortion of the triangle.

>Thanks for the updates!

What he said.

Trevor Green

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

Date: 26 Oct 90 13:42:25 GMT
From: unmvax!uokmax![e-mail]  (Jonathan A Bishop)
Subject: Re: "NAVY WITHHOLDING EVIDENCE"

[e-mail] writes:


>PLEASE GET MAD AS HELL LIKE I AM AND LETS WRITE LETTERS!!!

     The only thing I believe in this article is that he's mad.

--
[e-mail]

"Ground Control to Major Tom: Your circuit's dead; there's something wrong.
Can you hear me, Major Tom?" -- David Bowie

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

Date: 26 Oct 90 02:50:41 GMT
From: mnetor!utzoo![e-mail]  (Henry Spencer)
Subject: Re: photos from Voyager

In article <[e-mail]> [e-mail] (Arnold G. Gill) writes:
>     Now that the Neptune encounter is finished, and Voyager 1 has finished
>taking pictures of the Solar System, will any more photographic work be done
>by either spacecraft?  Or is it a case of there being no point to doing that?

No point and no plans.  The imaging systems have been shut down permanently.
(Well, they could be warmed up again, I think, but they might not work.)
There is nothing of interest to photograph any more.

>Were there ever any photos taken of Pluto, or others directed outside the
>Solar System?

Not photos, not really.  Pluto is too small and dim to get useful images
from such small telescopes.  Even the inner planets -- much bigger than
Pluto, and not much farther away! -- were just specks in the whole-system
photos.

There has been some use of the optical instruments for astronomy, notably
in the UV, but no imaging that I know of.
--
The type syntax for C is essentially   | Henry Spencer at U of Toronto Zoology
unparsable.             --Rob Pike     |  [e-mail]   utzoo!henry

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

Date: 26 Oct 90 02:39:59 GMT
From: mnetor!utzoo![e-mail]  (Henry Spencer)
Subject: Re: space news from Sept 3 AW&ST

In article <[e-mail]> [e-mail] (A Soldier Of God) writes:
>>Note that it is still the case that any satellite built in the US needs
>>an export license to be launched from abroad.
>
>Isn't it true that any no-government space launch needs an export license just
>to be  "exported" to orbit?

I don't think so.  This is a slightly strange situation, actually.  There
*is* historical justification for legal classification of space launches
as "export", since there have been a few instances of import duties being
refunded for items later launched (a diamond window for the Pioneer Venus
large probe being the example I remember).  But in general you do not need
an export license to launch something.

What you *do* need is a launch permit from the Office of Commercial Space
Transportation, plus FCC approval for any radio transmitters involved.
Nobody else has the authority to deny you launch permission in the US;
it was deliberately set up that way after Space Services Inc. publicized
the bureaucratic nightmare they had to wade through to get approval for
a private sounding-rocket launch.

Mind you, OCST is supposed to consider just about any conceivable issue,
including "the national interest", before giving you a permit.  And they
don't have to give a reason for refusing one.
--
The type syntax for C is essentially   | Henry Spencer at U of Toronto Zoology
unparsable.             --Rob Pike     |  [e-mail]   utzoo!henry

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

Date: 25 Oct 90 23:09:13 GMT
From: hplred![e-mail]  (Tom R. Myers)
Subject: Re: NAVY WITHOLDING EVIDENCE!!!

>  And do you have a name?

Its probably Elvis, and he wants his ship back from the Navy!


TRM

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

Date: 26 Oct 90 02:46:02 GMT
From: mnetor!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Pioneer 11 article

In article <[e-mail]> [e-mail] (John Webb) writes:
>>                                             ...  The single most prominent
>> result is fairly strong negative evidence that there is no major tenth
>> planet.  (The effects on the Pioneer/Voyager trajectories would have been
>> seen by now.) ...
>
>What part of an orbit would such a planet have to be in so that it
>would (or would not) affect the Voyager/Pioneer trajectories noticeably ?

As I recall -- dimly -- it would have to be well out of the ecliptic and
a long way out from the Sun.  The DSN tracking facilities are *good*; the
single biggest uncertainty in Pioneer and Voyager tracking is the slight
uncertainty in the relative positions of the tracking stations here on
Earth!  Spacecraft that have been in flight in the outer solar system
for 15 years make very sensitive detectors for unexpected gravitational
fields (after a very long list of *known* factors in their courses, notably
including both special and general relativity, is figured in).
--
The type syntax for C is essentially   | Henry Spencer at U of Toronto Zoology
unparsable.             --Rob Pike     |  [e-mail]   utzoo!henry

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

Date: 25 Oct 90 15:53:19 GMT
From: usc!zaphod.mps.ohio-state.edu!van-bc!rsoft!mindlink![e-mail]  (Bruce Dunn)
Subject: Re: Theory for Life


    Our genetic material is based on a double strand of DNA, with each strand
having the same information in complementary form.  DNA damage is repaired by
using the information in the other strand.  However, when there is extensive
DNA damage, and the information on both strands at the same spot is destroyed,
an organism has no way of recreating the information.
     On planets where life evolves under strong radiation or other DNA damaging
conditions, it is possible that life might evolve with a three-copy genetic
material, in which the information is redundantly stored in three strands (a
sort of triple helix, although the genetic material probably would not resemble
DNA in the least except for the concept that the order of subunits in a linear
polymer encodes the genetic information).  Such a genetic material could
withstand destruction of the information in 2 of 3 strands, or resolve
ambiguity in the message by a 2 out of 3 vote.  It would thus be much better
suited than a 2 strand system for survival of the genetic message in a hostile
environment.
     Higher organisms on earth are usually bilaterally symmetrical.  This
probably is a result of the inherent bilateral nature of 1 cell dividing into
two adjacent cells.  With triple stranded genetic material, a cell might divide
not into two cells, but into three cells.  This would bring up the interesting
idea that extraterrestrial life might be trilaterally symmetrical.  The body
form corresponding to our upright posture might then be something like a three
legged creature, with three arms.  What then would correspond to the "front"
and "back" of a bilaterally symmetrical creature?
--
Bruce Dunn   Vancouver, Canada    [e-mail]

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

Date: 26 Oct 90 23:21:59 GMT
From: optilink![e-mail]  (Clayton Cramer)
Subject: Re: Theories needed on life

In article <[e-mail]>, [e-mail] (Robert J. Knapp) writes:
> One question to the people saying "squat with massive internal
> skeletons/frames," is the verdict in or out on element other than carbon
> being used as the basis of chemistry in other orgs. it very S-F, but
> couldn't a Silicon or Germanium based life-form be denser and therefor
> able to attain heights close to human even on emmensly high G planets.
> I'm not sure but it think the basis for the arguement that life can be
> based on these elements is that they, like carbon have four bonding
> sights (more if they expand their outer shell) even if its not
> scietifically correct the idea has great potential for S-F stories.
>
>             Rob "I'm a physics major for now" Knapp

There's a problem with silicon based life -- silicon has a valence
of four, just like carbon, but the distribution of the elections
in the orbitals is different.  With carbon, there is one electron
in each of the four orbitals in the outermost shell.  This makes
it very easy for very complex carbon-based molecules to form,
in a variety of useful and interesting shapes.  Silicon has four
electrons in the outermost shell also, but there are two electrons
in each of two shells -- which makes covalent bonding of silicon
a little more fragile.  While aliphatic hydrocarbons of the form
C[n]H[2n+2] can easily form upto values of n >100, the equivalent
hydrosilicons aren't stable much above n = 5-10, tending to
oxidize readily into water and silicon dioxide.  (The Silicon
Monsters of Betelguse 5 land on Earth, intent on taking us over --
and as they open the spacecraft door, our atmosphere turns them into
burning blocks of wet quartz!)

The next time it rolls around on TV, watch _The_Monolith_Monsters_ --
a 1957 sci-fi film that never exactly addresses whether the
monsters are silicon-based life, or simply a "negative cleavage
crystalline structure" (to quote the film) mineral that rapidly
transforms the sand of the Mojave Desert into larger and larger
chunks of hexahedral silicon crystals.
--
Clayton E. Cramer {pyramid,pixar,tekbspa}!optilink!cramer
Alcohol prohibition didn't work; drug prohibition doesn't work; gun
prohibition won't work.
You must be kidding!  No company would hold opinions like mine!

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

Date: 26 Oct 90 21:37:15 GMT
From: sdd.hp.com!usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update - 10/26/90


                     GALILEO MISSION STATUS
                        October 26, 1990

     The Galileo spacecraft is just under 23 million miles from
Earth, approaching us from beyond Earth's orbit at a speed of
more than 25,000 mph.  Speed in solar orbit is 55,565 mph, and
round-trip communication time is down to 4 minutes 7 seconds.

     Spacecraft health and mission performance continue to be
excellent and close to predictions.  The engineering telemetry
rate is 1200 bits per second.  Spacecraft events are now under
the control of a new operational sequence, which took effect
Monday and will continue through December 7, the day before the
first Earth gravity assist.  This sequence continues the
relatively quiet level of activity seen over the past few months,
but with a gradually increasing amount of science activity.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date: Fri, 26 Oct 90 19:21:51 EDT
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: LLNL Proposal


>From: "Allen W. Sherzer" <[e-mail]>
>Subject: Re: You Can't Expect a Space Station to be Cheap

>I should also add that the LLNL station is designed for a life of ten
>years not thirty. But since it costs less than 5% of what Freedom costs
>this shouldn't be viewed as a problem.

As several people have pointed out, there are advantages to being able
to periodically update the design.

>>2 - Radiation - need to guarantee to operate after a 30 year dose in LEO
>>(crews rotated every 90 days) kinda restricts the electrical design;

>My sources do not say anything on this for the Earth Station, just for
>the trip to Mars. However, in my readings of NASA objections to the
>Great Exploration they make no mention of it. It could be that LLNL
>presented an approach NASA accepted.

I don't think the electronics, etc. are *expected* to last 30 years -
that's what all the _maintenance_ is about (replacing components).

>>4 - Can LLNL assemble their Fred equivalent system using 22 shuttle
>>flights?   This means weight is a big issue.

>The LLNL Earth Station goes up in 1 HLV flight. This can be done because
>the inflatable structures greatly reduce weight and launch volume. In
>[1], ILC states that the packed volume of the Earth Station would be
>28.8 cubic meters for an all fabric design and 31.6 cubic meters for
>a design with hard pressure bearing floors. The total weight budget
>is 40.4 tons, but that includes everything.

How about in several smaller pieces?

>They are. They are preparing by being up front with the risks involved.
>Challenger was a disaster because people felt betrayed. NASA told them
>the system was safe enough to send a school teacher. Had they been
>more honest Challenger wouldn't have been so big a deal.

That was *part* of the problem. Most of the problem is that Americans (and
people in other countries too, I suppose :-) are basically idiots when it
comes to risk analysis. People regularly get very upset over some tiny
hazard while ignoring much worse safety problems (i.e. the anti-nuke people).
NASA has been trying for the last few years to convince people that a
calculated probability that another Shuttle orbiter could eventually be
lost should be regarded as a normal part of doing business, and the message
never seems to sink in:

Q:    You mean we could lose ANOTHER orbiter?
NASA: Yes, despite all our safety precautions, if we fly a sufficient number
      of missions, we can expect eventually to lose another orbiter.
Q:    You mean BOOM?
NASA: BOOM.
Q:    Really?
NASA: Yes.
Q:    You're obviously criminally insane. How can you let those astronauts
      risk their lives like that? Don't you want to make sure the Shuttle is
      completely safe?
NASA: If zero risk is the standard, nobody can fly any missions. We maintain
      a very high level of safety by industry standards, which is one reason
      why the Shuttle costs so much.
Q:    I see. So how long have you been keeping this evil secret?
NASA: We're not keeping it secret - we're trying to get the message out, but
      nobody pays any attention. Didn't you read that big billboard out on
      the highway?
Q:    I was too busy trimming my nails, eating lunch, and reading a road map
      while driving my old car with the bald tires and bad steering, and
      the kids were climbing over the seats. But as I was saying, how can
      you take such risks?
... and so on.

In this environment, it's hardly surprising that NASA has strange priorities
regarding safety.

>>    NASA clearly does not want anything like that to happen again, and
>>safety costs money guys, sorry but that is just the facts of life.

>NASA levels of safety will cost us half a trillion dollars to get to
>Mars. We can't affoard that.

>[3] NASA Assessment of the LLNL Space Exploration Proposal and LLNL
>    Responses, LLNL doc. no. SS90-9 page 27.

Could you quote the part about the batteries?

In general, I think the LLNL inflatable station proposal is a very interesting
idea, and probably worth pursuing, though I also suspect NASA is somewhat
justified in its pessimistic assessment of its being fully as cheap and
successful as predicted. It certainly shouldn't cost much to find out in
relation to the full cost for Freedom. The LLNL proposal could even be
justified as a "practice" space station, adding only a few percent to the
cost of the Freedom project.
     John Roberts
     [e-mail]

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

Date: 26 Oct 90 11:33:06 GMT
From: eru!hagbard!sunic!mcsun!hp4nl!phigate!philtis!mswe![e-mail]  (Newsmgr @ Philips Medical Systems)
Subject: test

aodifjaod

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

End of SPACE Digest V12 #501
*******************