Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V15_2/V15NO207.TXT

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Date: Wed, 16 Sep 92 05:04:06
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #207
To: Space Digest Readers
Precedence: bulk


Space Digest                Wed, 16 Sep 92       Volume 15 : Issue 207

Today's Topics:
                          Asteroid explorer
         Is NASA really planning to Terraform Mars? (2 msgs)
               Magellan Begins Gravity Mapping of Venus
                          plantary formation
               Pluto Direct Propulsion Options (2 msgs)
                         Population (2 msgs)
                       Probes - self portraits?
            Problems answering people from The Federation.
                   QUERY Re: Pluto Direct/ options
                       TOPEX Update - 09/14/92
                           Who went to Rio?

    Welcome to the Space Digest!!  Please send your messages to
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Date: 15 Sep 92 20:41:58 GMT
From: Nick Szabo <[e-mail]>
Subject: Asteroid explorer
Newsgroups: sci.space,sci.astro,alt.sci.planetary

[Phil posts neat idea for hitting asteroid with a tank and measuring
the seismic effect]

Along these lines, perhaps we can steer upper stages headed for
deep space into intercept trajectories, and get some observing
time on a big telescope like Keck or Hubble to see what happens.
For example, could Mars Observer's TOS be steered into Phobos,
or would we have had to tinker with TOS's navigation box beforehand?
Do we know Phobos' orbit well enough to steer blind?  What
could we learn by doing imaging and spectroscopy on the resulting Phobos
debris cloud?  I suspect this would be a great way to learn what lies
underneath the surface layer of regolith.

The collision wouldn't damage Phobos, just put another impact
crater on it.  Some future isotopic ratio studies might be
effected, and the spectroscopy study itself would have to factor
out the TOS debris.


--
[e-mail]        Tuesday, November third  ##  Libertarian  $$  vote
Tuesday  ^^ Libertarian  --  change  **  choice && November 3rd @@Libertarian

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

Date: 15 Sep 92 14:01:27 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Is NASA really planning to Terraform Mars?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Josh 'K' Hopkins) writes:
>[e-mail] (Paul Dietz) writes:
>>Your non sequitur appears to be the following: If there is
>>overpopulation, then people would starve.  People are starving.
>>Therefore, there is overpopulation.
>
>I think my question was legitimate.  Do you believe the situation is going to
>improve as population gets larger?  I'm not so worried about "overpopulation"
>per se.  What I do believe is that allowing people to have control of the
>number of children they raise will result in a lower growth rate, which I
>believe to be an improvement.

Two things. As world population has grown, both the percentage and the
absolute numbers of malnurished people have diminished. I won't attempt
to imply causation here, just reporting the fact. The second thing is
more to the point. In subsistence agricultural communities with poor
health care and a non-existant social safety net, having more children
is an *advantage* for the people. The high birth rate makes up for the
high infant mortality rate and provides them with additional laborers
in the fields and a fairly large group of descendants to take care of
them in their old age. Merely providing birth control without also
supplying these other necessities would be doing these people a
disservice.

Farm family size in the US has decreased as mechanization and social
services have improved. This is also true of non-farm families.
The shortage in subsistence communities is almost always labor. Only
6% of the arable land in Africa is farmed. That's because there isn't
enough labor available to productively use the land with pre-industrial
techniques. Using standard Green Revolution techniques, Africa should
easily be able to increase it's yield of foodstuffs by 40 times it's
current production. Minus the effects of tribal warfare, current farm
production in Africa is sufficient for the current population. This isn't
meant to imply that increasing Africa's population by 40 fold would
necessarily be a good thing, but it is possible for them to feed that
many with known techniques.

Gary

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

Date: 15 Sep 92 19:18:30 GMT
From: Paul Dietz <[e-mail]>
Subject: Is NASA really planning to Terraform Mars?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:

 > The shortage in subsistence communities is almost always labor. Only
 > 6% of the arable land in Africa is farmed. That's because there isn't
 > enough labor available to productively use the land with pre-industrial
 > techniques. Using standard Green Revolution techniques, Africa should
 > easily be able to increase it's yield of foodstuffs by 40 times it's
 > current production.

Actually, about 30% or so of the arable land in Africa is currently
farmed (the 6% figure refers to one of the countries where food prices
are being held artificially low.)  Africa has about twice as much
arable land as the far east, but has a lower population.

There are two major problems with African agriculture.  The first is
that the soil is mostly poor.  Unlike the temperate regions, the soil
has been leached for millenia by tropical rains without replenishment
from glaciation (which grinds up nutrient-rich bedrock and spreads it
across the land).  African soils are often red and acidic, and in some
places nutrient mining is occuring, with declining yields.  The upside
of this is that the land responds readily to fertilizer, properly
applied.

The second problem is that 80% of farming in Africa uses manual labor;
not even animal labor (due to the tsetse fly).  This is the reason for
the unused land; a family can farm only about 2 1/2 acres without
animals.

The Op-Ed page of the NY Times yesterday (9/14/92) had a piece on Dr.
Norman Borlaug (1970 Nobel Peace Prize winner for hybrid wheat, which
has helped China to become the world's leading grain producer and
India to quintuple wheat production since 1967), who is trying to get
Africa to use existing knowledge on fertilizers, plant varieties, pest
and moisture management.  His team has applied this knowledge to
150,000 farms in Africa, increasing the yield by an average of 2.5
times.  Borlaug started in 1986 with wheat and sorghum in the Sudan
and maize in Ghana.  Ghana's maize production is up 40%; wheat
production in the Sudan increased from 160,000 tons in 1986 to 800,000
tons in March of this year.


    Paul F. Dietz
    [e-mail]

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

Date: 16 Sep 92 04:37:18 GMT
From: Ron Baalke <[e-mail]>
Subject: Magellan Begins Gravity Mapping of Venus
Newsgroups: sci.space,sci.astro,sci.geo.geology,alt.sci.planetary

Michael Braukus
Headquarters, Washington, D.C.           September 15, 1992
(Phone:  [phone])

Jim Doyle
Jet Propulsion Laboratory, Pasadena, Calif.
(Phone:  [phone])

RELEASE:  92-148

NASA SPACECRAFT BEGINS GRAVITY MAPPING OF VENUS

    The Magellan spacecraft's orbit at its closest approach
to Venus was lowered Monday and today it began a full 243-
day cycle of gravity mapping, project officials at NASA's
Jet Propulsion Laboratory, Pasadena, Calif., said.

     Magellan has now completed three cycles of mapping
with its  radar, covering 99 percent of the surface of
Venus.  Monday, controllers ordered a 1-hour orbit
adjustment burn to lower its periapsis -- closest approach
to the planet -- altitude from 160 miles (258 kilometers)
to 113 miles (182 kilometers).

     "That will help us obtain the best possible resolution
in the equatorial latitude gravity map," Project Manager
Doug Griffith said.

     The objective of cycle 4, which extends to May 15,
1993, is to obtain a global map of the Venus gravity field
from the elliptical orbit.  The orbit apoapsis, or furthest
point from the planet, remains the same, 5,296 miles (8,543
kilometers).

     During this fourth cycle, variations in the
gravitational pull experienced by the spacecraft are being
recorded by carefully tracking the Doppler shift of a radio
signal that Magellan will constantly beam to the Deep Space
Network tracking stations.

     When Magellan passes over a dense region of Venus'
interior, for example, the spacecraft accelerates in its
orbit and the location of the denser region is mapped.

     Over the course of the 243-day cycle, one rotation of
Venus, variations in the planet's density will be mapped at
a resolution much higher than achieved by previous
missions.

     Looking at the interior with gravity observations is
expected to provide an improved understanding of the forces
of tectonics and volcanism that shape the planet.

     Magellan is managed by the Jet Propulsion Laboratory
for NASA's Office of Space Science and Applications,
Washington, D.C.
- end -
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Quiet people aren't the
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | only ones who don't say
|_____|/  |_|/       |_____|/                     | much.

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

Date: 15 Sep 92 19:34:29 GMT
From: Marc Allan Rouleau <[e-mail]>
Subject: plantary formation
Newsgroups: sci.astro,sci.physics,sci.space

    I am working on a project here at WPI to examine theories on the
origin of the solar system.  Can anyone suggest some good books, articles,
etc.  In particular I am interested in the particular distribution of the
planets' masses - large in the middle and progressively smaller towards the
ends (or more or less so).  Thanks.
                        Marc A. Rouleau
                        [e-mail]


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

Date: 15 Sep 92 20:16:10 GMT
From: Nick Szabo <[e-mail]>
Subject: Pluto Direct Propulsion Options
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Phil G. Fraering) writes:
>[e-mail] (Henry Spencer) writes:

>(I can hear them now. "Eeek! deployable! Ever since Galileo, we're not
>supposed to use deployable structures until hell freezes over! We're
>supposed to be stuck with whatever can fit inside the payload shroud
>until the end of time!" Why not just _not_ drive the probe across the
>country half a dozen times before launch?)

Well said.  Note that the TDRSS's had the same kind of deployable
antenna as Galileo, and they unfolded without a hitch.  In fact,
there have been dozens of successful automated deployments on all
kinds of spacecraft, from spysats to comsats, most in places where
astronauts cannot go.


--
[e-mail]        Tuesday, November third  ##  Libertarian  $$  vote
Tuesday  ^^ Libertarian  --  change  **  choice && November 3rd @@Libertarian

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

Date: Tue, 15 Sep 1992 20:13:12 GMT
From: Dave Tholen <[e-mail]>
Subject: Pluto Direct Propulsion Options
Newsgroups: sci.space,sci.astro

Ian Taylor writes:

> My understanding is that our current knowledge about Pluto is minimal, is it
> established that Pluto even has an atmosphere?

Absolutely.  The 1988 stellar occultation experiment is the evidence.  Check
out Elliot et al. in, if I remember correctly, the first 1989 issue of Icarus.

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

Date: 15 Sep 92 18:18:09 GMT
From: Doug Mohney <[e-mail]>
Subject: Population
Newsgroups: sci.space

Reply-To: [e-mail]
Organization: Computer Aided Design Lab, U. of Maryland College Park
Lines: 60
Sender: [e-mail]
Source-Info:  Sender is really [e-mail]

In article <[e-mail]>, [e-mail] (Josh 'K' Hopkins) writes:

[ in the truest sense of out of control topic growth.....]

>First, I'd like to point out that I'm not the same person who wrote the follow
>up to my post, nor do we agree on all things.  Doug lumps us togther.  Since
>the mid 80's, America has stopped giving moneyt to the UN agency that works to
>combat population growth in the third world.

We stopped giving money to UNESCO, the educational and cultural part of the UN,
along with a lot of other folks, because they were gold-plating their office in
France. Literally. They started getting their act together, so the taps have
been open.

The <mutter/grumble> Reagan adminstration stopped giving money to some non-UN
organizations which were "promoting" abortion as a means of birth control.

>Come to think of it, I believe we don't give the UN any money anymore.

We give them money. We don't give them as much money as we owe them; I think
we're back-debted at least $300-450 million; don't have a ready reference for
that here.

> Anyway, my point is the following,
>given that there is an unfulfilled demand for birth control (I don't think I've
>cited sources here, but if you want I'll dig some up) and that population
>growth in the third world tends to eat up progress made by foreign aid,

This was one of these paradoxes of the 60's and 70s. We provided modern health
care first in the form of vaccinations and other (minor for First world)
improvements without anticipating the growth in number of mouths to feed.

ANYwhooo, there are any number of organizations, both publically and privately
funded, which are providing family planning/birth control information and aid
to these places. However, until you reduce the incentives for big families
through economic growth (i.e. turn 'em into capitalists :-), the individual
family is going to continue to have kids.

UN(?)fortunately, the spread of AIDS is going to adversely affect the Third
World. Serious war going on to promote condom usage, which may (should) also
check population growth. Unless condoms aren't used, in which case population
growth will (alas) be checked by biological means.

>But transitions take a while.  The people who are working on electric vehicles,
>which may eventually be quite competitive with gas powered ones, or solar
>thermal power, or finding ways to _save_ money through conservation are doing
>it because it's a good investment.  The substitutes you're talking about are
>being worked on now, but you're slamming them.

I am not slamming substitutes. I am slamming crash programs to throw money at
problems which, as the Synfuels debacale of the Carter Administration showed,
doesn't really work.

But, how we solve the problems of the world rather than NASA is drifting wayway
way down the yellow brick road.


                 Play in the intelluctual sandbox of Usenet

  -- >                  [e-mail]                        < --

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

Date: 15 Sep 92 15:04:42 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Population
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Josh 'K' Hopkins) writes:
>
>First, I'd like to point out that I'm not the same person who wrote the follow
>up to my post, nor do we agree on all things.  Doug lumps us togther.  Since
>the mid 80's, America has stopped giving moneyt to the UN agency that works to
>combat population growth in the third world. Come to think of it, I believe
>we don't give the UN any money anymore.

Indeed we are fully paid up members again since Desert Storm. The US had
been withholding $425 million dollars in dues to the UN prior to the war,
but when the SC came through and backed the US, we coughed up the money.

>                                            Anyway, my point is the following,
>given that there is an unfulfilled demand for birth control (I don't think I've
>cited sources here, but if you want I'll dig some up) and that population
>growth in the third world tends to eat up progress made by foreign aid, it makes
>sense to help reduce growth - where the assistance is desired - instead of
>sending cash.  I then went on to suggest that lowering growth would be more
>likely to help  stabilize the region that not lowering growth.

In most subsistence cultures there is *no* demand from the indigenous
population for birth control. Indeed, extra hands are the only resources
that they can produce. There is a labor *shortage* in Africa, and most
of the rest of the third world. This may seem surprising, but it's true.
The low productivity of labor without benefit of mechanical and technical
amplification is such that many many hands are needed for the most basic
jobs. In some parts of Africa, farmers still use wooden digging sticks.
A modern (19th Century) steel moldboard plow would make more difference
to these people than any amount of birth control equipment.

[re: transistion from an oil economy]
>But transitions take a while.  The people who are working on electric vehicles,
>which may eventually be quite competitive with gas powered ones, or solar
>thermal power, or finding ways to _save_ money through conservation are doing
>it because it's a good investment.  The substitutes you're talking about are
>being worked on now, but you're slamming them.

Electric vehicles aren't what's being talked about here. At $35 a barrel
equivalent, alcohol produced from biomass is economical with known and
tested techniques available *now*. At $55 a barrel equivalent, Fischer-
Topish (sp) process synthetic gasoline from coal or shale is economical
and feasible with techniques known and tested in volume production over
50 years ago. As the price of oil eventually rises, there are known,
developed, and available alternative liquid fuel technologies that will
come on line to take the place of oil. This is a solved problem.

Electric vehicles are touted for two main reasons. One, they have low
point of *use* emissions. And two, they are the ultimate multi-fuel
vehicle since any fuel that can be used to make electricity can power
them. However, the storage battery problem remains intractable after
over a century of development. Electric vehicles, if they become common,
will be externally powered or have short range and a limited performance
envelope until the battery problem is licked. I don't hold out much hope
that a miracle battery is on the horizon that will change this. Battery
science is as complex, if not more so, as rocket science. Rocket science
hasn't delivered cheap payload of orbit, and battery science hasn't
delivered cheap, light, high capacity batteries. Some here would claim
that that's *because* of government funded research, not in spite of it.

Gary

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

Date: Tue, 15 Sep 92 19:41:16 GMT
From: Joshua Bell <[e-mail]>
Subject: Probes - self portraits?
Newsgroups: sci.space

I've often wondered, especially in the wake of Gallileo's stuck
HGA, but also after Voyager 2 headed off into never-never land
past Neptune, why the cameras on these craft are unable to be
located so that they can take images of the craft itself, for
self-diagnosis, and also for PR - I would have LOVED a rather
non-scientific shot of Voyager 2 looking back over its own
shoulder towards Neptune, or during the fly-by, so we can see the
various parts of the craft. Venera landers returned pictures of
their own shadows (I'm sure others did as well, but I remember
the Venera pic best), and Viking was designed to look at parts of
itself (eg, the color bar, the sample arm, etc) - is there no
hope for non-lander probes? Must we be content with the animation
(I'm still in awe of James Blin's [did I spell it right?] Voyager
2 animation tho. :)

Joshua
| Tremble only if you build false accounts and stand pridefully upon them    |
|                                       - Lord Leto II, God Emperor of Dune  |
|                                                                            |
| [e-mail]  Academic Computing Services, University of Calgary |

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

Date: 15 Sep 92 15:15:05 GMT
From: [e-mail]
Subject: Problems answering people from The Federation.
Newsgroups: sci.space

Path: acad2.alaska.edu!asljl
From: [e-mail]
Newsgroups: sci.space
Subject: The Federation is still here
Message-ID: <[e-mail]>
Date: 11 Aug 92 15:59:53 AST
Organization: University of Alaska
Lines: 34

Path: acad2.alaska.edu!asljl
From: [e-mail]
Newsgroups: alt.alien.visitors
Subject: The Federation is still here
Message-ID: <[e-mail]>
Date: 11 Aug 92 15:53:25 AST
Organization: University of Alaska
Lines: 25

Hello All

Yes, The Federation is still here, at the moment for those still
interested, it is still here and still reachable. We still want to
hear from people interested in it or new people interested in the
Federation.
    For those of you who are new to the Federation ideas, this is
what we are:  We are a group of people who feel it is high time we got
off this rock and started exploring the great unknown of space.  We have
drawn out in blue print form a drive system that is a a super semi conducting
crystaline structure. It looks good on paper but we haven't been able to
test it yet. As always the problem is money. The Federation has been working
on a personal funds of the few members base at the moment.  We do have a
info packet that we will happy to give you. You must have a mac that has
5.0 microsoftword or better. Send us a 3.5 floppy and we will put it
on there for you. send to this adrress

The Federation
C/O Lady Rhavyn
Po box 231772
Anchorage, Alaska
          99523-1772

If you have any questions feel free to send to this account.

[e-mail]

********************************************************************************

    I have had a problem sending the small version of the Federation
Manual overthe E - Mail system.   It seems it does not like some the of the
addressesI am using that people send me.  Please be sure that you include in
your E-mail request, your internet/bitnet E-mail address so that I have the
correct address to send it to you.
    My problem has been that I have had to, on occassion take it off the
beginning of your messages.  Either I am  not copying it down correctly or
the computer is scrambled, or it does not like the address and so I get a
message from the postmaster telling me it doesn't like that address.  I do
apologize to those of you who asked for the info and never received it. Please
try again.

Member of the Federation
* May the Force be With You *

Thank you
Sincerely
Lady Rhavyn
Memeber of the

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

Date: 15 Sep 92 20:22:54 GMT
From: Dave Tholen <[e-mail]>
Subject: QUERY Re: Pluto Direct/ options
Newsgroups: sci.space

Mark Brader writes:

> Several slingshot trajectories have been proposed as alternatives to the
> direct Pluto flight, but not the one that I would have thought obvious:
> a simple Jupiter slingshot.  Jupiter should be in the right position
> for a period of, I would guess, some weeks or months, at intervals of
> about 12 years.

The Jupiter slingshot has, I can assure you, been proposed.  Yes, Jupiter
is in the right position about every 12 years, but the interval can be
as long as two years.  If you go for the earliest opportunity, the bending
angle at Jupiter is rather severe, requiring a very close approach, and
consequently lots of radiation shielding.  This essentially sets the limit
for how early one can use Jupiter for a gravity assist.  At the late end,
you're limited by the law of diminishing returns:  little bending angle,
little gravity assist.  The next Jupiter alignment that could be used for
a Pluto mission is in the 2002 to 2004 time frame, and that was the window
the Outer Planets Science Working Group had its eye on before Goldin took
over as NASA Administrator.  He favored a "faster, smarter, cheaper,
sooner" approach, and that's when direct trajectories were given more
serious consideration.

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

Date: 16 Sep 92 04:33:53 GMT
From: Ron Baalke <[e-mail]>
Subject: TOPEX Update - 09/14/92
Newsgroups: sci.space,sci.geo.meteorology

Forwarded from:
PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. [phone]

                  TOPEX/POSEIDON STATUS REPORT
                       September 14, 1992

          The TOPEX/Poseidon satellite is performing nominally
and is healthy.  Attitude control, solar array, batteries,
telecommunications, and the on-board computer are all functioning
normally.

          In-Plane Maneuver #3 was performed successfully today.
This was the first burn performed using the four, small 1 Newton
thrusters.  The next TRIM Maneuver is scheduled for Monday, Sept.
21.

          The NASA altimeter remain in idle mode while the SSALT
is in track mode.  The SSALT will be turned off today and the
NASA altimeter will be commanded to track.  Over the weekend, the
SSALT had near overflights of both the NASA and CNES verification
sites.  Also, the SSALT overflew hurricane Iniki on several orbit
passes over the Pacific Ocean.  Before it was put into idle mode,
the NASA altimeter recorded 24-foot waves in the Pacific,
presumably due to the hurricane.

          Project engineers are analyzing why the Global
Positioning System Data Recorder failed to come out of idle mode
today when it was commanded to track.  Over the weekend the GPSDR
memory was reloaded, readout, and a checksum was verified.

          The satellite is now sharing TDRSS resources with the
shuttle.  TDRSS support continues to be excellent with no
significant impact to our mission.

                             ######
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Quiet people aren't the
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | only ones who don't say
|_____|/  |_|/       |_____|/                     | much.

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

Date: 15 Sep 92 21:11:09 GMT
From: Nick Szabo <[e-mail]>
Subject: Who went to Rio?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Bill Higgins-- Beam Jockey) writes:
>
>At the moment, "moving some industry off Earth," as a method of
>"saving the environment," must be viewed as pure science fiction.

It is, however, a valid response to "look at all the exponential
growth of this and that, we're going to destroy our planet in
a hundred years!", which is also science fiction.


--
[e-mail]        Tuesday, November third  ##  Libertarian  $$  vote
Tuesday  ^^ Libertarian  --  change  **  choice && November 3rd @@Libertarian

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

End of Space Digest Volume 15 : Issue 207
------------------------------