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Subject: SPACE Digest V12 #515

SPACE Digest                                     Volume 12 : Issue 515

Today's Topics:
               Canals on Mars?
                   Re: X-15
            AP story on NASA's 1991 budget
           Re: Pioneer 11 Update - 10/30/90
              Re: LLNL Proposal
             Mars Rover Update - 10/26/90
       Re: You Can't Expect a Space Station to be Cheap
        Re: A great idea on how to fund NASA!

Administrivia:

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

Date: 30 Oct 90 13:25:09 GMT
From: ubc-cs!news-server.csri.toronto.edu!utgpu!watserv1!ria!uwovax![e-mail]
Subject: Canals on Mars?

Regarding Martian Canals:

     The originator of the canal story was Giovanni Schiaparelli, an
Italian astronomer, who in 1877 first mapped a complex web of narrow
lines on Mars (others had seen a few in previous oppositions). He called
them 'canali' meaning channels, and remained studiously vague about how
they might be interpreted. In 1896 Percival Lowell began observations of
Mars and developed his famous theory of an advanced civilization, a drying
desert world and irrigation canals. Cerruli, Brenner and many others
followed suit. Many 'saw' canals but there were always other explanations,
so many believed in canals without believing in irrigation. For instance,
Richard Proctor mapped them as rivers (See SCIENTIFIC AMERICAN
SUPPLEMENT for 1888). Lowell's ideas became more famous because they were
more extreme. The greek-french astronomer E.M. Antoniadi, one of the
greatest visual observers of early this century, began by mapping canals but
by the 1920s saw them for what they in fact are, essentially random
blotches in a complex landscape (most of the blotches being dark boulder
fields or sand dunes, the brighter areas being dustier). His great book
'La Planete Mars' in 1930 really killed the canals....for most. actually,
the idea had such powerful public appeal that the first maps of Mars
drawn for NASA in 1962-5, to help plan the Mariner 4 observations, still
showed canals. These were by the U.S. Army Map Service and U.S. Air Force
Aeronautical Chart and Information Center. Naturally, Mariner 4 wiped out the
canals, but replaced it with another misconception which lasted for about
5 years - namely that Mars was moon-like. By the way, some might claim that
the canal Agathodaemon (or Coprates) really did exist because it is the dark
floor of the Valles Marineris. Not really - it is qualitatively different
from all the rest of the canals, more akin to the regular dark areas and as
such visible in telescopic drawings long befor the canals were discovered.

Phil Stooke,
Department of Geography,
University of Western Ontario,
London, Ontario, Canada N6A 5C2

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

Date: 31 Oct 90 04:36:44 GMT
From: uokmax![e-mail]  (Jonathan A Bishop)
Subject: Re: X-15

[e-mail] (alan pengelly) writes:

> I've just read a very interesting book on the evolution
>of the USA's winged spacecraft program (X-1 to Shuttle).
>What strikes me most was the X-15 programme, which
>was a fine piece of research, and which to me seemed to
>be under exploited. In particular the decision not to
>go for an uprated version (delta-winged + more power).
>Given the X-20 cancellation as well, it seems to me that
>the US was well ahead in this field quite early on, but
>seemed to back-off. Was it money, was it apollo? Does
>any one know what the capabilities of the uprated X-15
>were to be, ie speed and altitude? Also given what is
>known now, would the X-20 have worked?

Sounds like it's Melvyn Smith's book.  Yes, it is very good.

The uprated delta X-15 would have been launched from an XB-70 to give
it a much greater initial velocity boost than the NB-52 could.  The
only real uprated X-15 was the X-15-A2 modification.  The external fuel tanks
it carried enabled the engine to burn longer, resulting in greater speeds;
however, skin heating was much more severe than had been expected.  To cope
with this, the white ablative coating was added, but it was heavy.  In the end,
the A2 reached Mach 6.7.  By this time, the limits of the XLR-99 were being
pushed again.  A planned modification would have added a ramjet.  On the
record setting flight, a mockup was carried, but a lambda shock caused by
interference between the ramjet shock wave and the fuselage shock wave
developed, burning the ramjet off and severely damaging the coating.  The
plane was never flown again.  Without the extra fuel tanks, neither of the
other X-15's could continue the high speed program, but they continued high
altitude flights.  I don't know exactly what the delta wing's performance
would have been, but I can't see that it could have been more than about
Mach 7 or 7.2 due to heating.  It could have gone higher than the plain X-15.

After reading the Smith's book, I too became interested in the X-20.  I have
written two short research papers on the subject.  My main information source
is an acquaintance who is doing his doctoral work in history on the X-20.
The stated reason for cancellation of the X-20 was cost overruns and lack of
results.  Bob McNamara felt that the Manned Orbiting Laboratory, a Gemini
variant, would be more cost effective (he later cancelled it, too).  There
are other reasons too, though.  The X-20 was the first step in a three
stage program to build an orbital or sub-orbital vehicle usable as a bomber,
a troop transport, or other weapons platform.  I believe (OPINION) that its
development could have easily prompted a war with the Soviet Union.  The
technology, though, was not too sophisticated; we could have done it.  If we
had, I think that we would just now be going to the Moon for the first time,
but we would be going to stay, and we would have built a permanent space
station around 1975.
--
[e-mail]

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

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

Date: 31 Oct 90 01:32:40 GMT
From: osu-20.ircc.ohio-state.edu![e-mail]  (Robert Bunge)
Subject: AP story on NASA's 1991 budget


10/30/90

WASHINGTON (AP) _ President Bush's most ambitious space proposal _
colonizing the moon and sending a manned expedition to Mars _ are
casualties to the deficit-cutting bill approved by Congress.


The AP story reported the 1991 budget planners cut $37 million for early
studies in Mars and Moon trips and trimmed at least $500,000 from the
space station project.

But, even with these cuts, NASA's budget was increased $1.6 million. The
increase was a good bit smaller than what the administration had asked for.
Bush had asked for a increase of $2.9 million.

Buried at the bottom of the report is that Congress added $30 million to
the $294 million Bush had requested for the operation and upgrade of HST.
The report also said "Since (launch), the $1.5 billion instrument has
malfunctioned."

Apparently Bush's proposed HST budget was made before the launch and
discovery of the spherical abberration.

Budget trimmers also cut $210 million in research and technology, leaving it
at the same level as 1990.  $24 million was trimmed from the National
Aerospace plane.

$53.9 million was cut from the requested $4.4 billion shuttle operations
budget and $30 million was trimmed from NASA's $53.9 million request for
design of the next generation of (unmanned?) rocket.

Finally, life sciences research was cut $25 million but, $12.1 million was
reserved for SETI operations.


Bob Bunge
[e-mail]

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

Date: 30 Oct 90 16:58:16 GMT
From: lib![e-mail]  (Jay Maynard)
Subject: Re: Pioneer 11 Update - 10/30/90

In article <[e-mail]> [e-mail] (Ron Baalke) writes:
>                             Pioneer 11 Update
>                             October 30, 1990
>     The Pioneer 11 spacecraft emergency was terminated at 3:29PM (PST)
>yesterday.

OK, I'll bite...how was it terminated? Did we get it back? Is it lost for good?
Is some of it working, but not all? Inquiring minds want to know.
--
Jay Maynard, EMT-P, K5ZC, PP-ASEL | Never ascribe to malice that which can
[e-mail]  | adequately be explained by stupidity.
         "With design like this, who needs bugs?" - Boyd Roberts

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

Date: Tue, 30 Oct 90 19:37:20 EST
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: Re: LLNL Proposal


>From: zaphod.mps.ohio-state.edu!wuarchive!rex!rouge![e-mail]  (Fraering Philip)
>Subject: Re: LLNL Proposal

>In article <[e-mail]> [e-mail] (John Roberts) writes:
>>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:

>Well, the public in general realizes the risks.

They realize there is a risk, but they have no way to quantify it or deal
with it. The general view seems to be that there is no appreciable difference
between a probability of one in ten and a probability of one in ten million.
Countless examples come to mind, one of the better-known being the obsessive
buying of large numbers of lottery tickets. A more immediate example for
those living in the US (Canada too?) is "trick-or-treating" on Halloween
(October 31), in which traditionally, costumed children visit neighborhood
houses and ask for candy. This is done far less than in the past, because
a very few kids get contaminated candy, and every parent is sure that his/her
kid will get some too. Then some of these same parents go out and buy their
children off-road vehicles, or passionately fight against bicycle helmet
laws. In the same way that a cat may appear to be very clever in many ways,
but will act stupidly in situations to which it is not well adapted, most
people seem to walk through life in a sort of haze as far as effective risk
assessment is concerned, and yet feel themselves fully qualified to call for
stupid laws and stupid public policy decisions. The cat can't help it -
for people it's through lack of proper education or through just not
caring to think things through. I believe risk assessment for decision
making would be a very good topic for greater emphasis in our educational
system.

>What upsets the
>public in general, and those of us who track space in particular, is
>that the shuttle, which is so expensive in the first place, is so
>unsafe.

Perhaps in relation to commercial airliners, for instance, but what about
in relation to other launchers? I would welcome reliable statistics on
Soviet launchers, but in the continuing absence of such, I can say I have
seen no solid indication that the Shuttle is not the safest orbital launcher
in existence. NASA considers it safer than any other US or European launchers.
There are valid complaints that can be made about the Shuttle (notably cost
and difficulty in meeting tight schedules), but given the current level of
the art, I don't think safety is one of them.

>It's not just the chance that another orbiter will be lost. It's the
>chance that $ 3,000,000,000.00 (count those zeroes and imagine) worth
>of sophisticated hardware will be broken up into bite-sized pieces,

Every time a Titan IV is launched, ~$100 million of hardware ends up in the
ocean. A year of launches in a worthy cause that wound up with $3 billion in
the ocean would make everybody happy. For true cost of Shuttle accidents,
one should consider the expected monetary losses from such in comparison to
the total cost of maintenance, mission control, depreciation, and so on.
I think most studies indicate that the expected cost from orbiter loss is
only a small fraction of the total, which is another way of saying that
perhaps too much emphasis is placed on safety.

I agree with you that the public is likely not to perceive things this way,
again due to lack of education in the matter. There is also no consistent
viewpoint on what the valuation of a human life should be.

>Phil Fraering
>[e-mail]
       John Roberts
       [e-mail]

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

Date: 31 Oct 90 00:27:18 GMT
From: usc!zaphod.mps.ohio-state.edu!sdd.hp.com!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Mars Rover Update - 10/26/90

From the "JPL Universe"
October 26, 1990

"Robby Roves Arroyo as Prelude to Mars"

     JPL scientists and engineers have for the first time programmed a
computer-driven planetary vehicle to traverse 100 meters of rugged natural
terrain without human guidance.  The test in September was considered a
significent milestone in development of a semi-autonomous navigation system
for a planet-roving vehicle.

     A mission using a computerized rover is expected to precede any manned
mission to another planet.  The rover, called "Robby" by the Section 347
experimenters, covered the 100 meters in about 4 hours and 20 minutes,
moving cautiously about two meters at a time, then stopping to survey
ahead another two meters.

     The test was in the rugged Arroyo Seco between the east lot and Oak
Grove Park.  The course was not preprogrammed in that the end of the course
was not in the vehicle's stereo vision.  It was obscured by foliage and
rocks and no information about the specific terrain was provided in the
testbed computer.

     By using the stereo television cameras, Robby surveyed the area and made
its own map, two meters at a time.  When it encountered a flat plane, it
proceeded directly toward the goal, when it encountered an obstacle, it made
a new map and modified its path to go around it, rather than over it.

     The unprecedented accomplishment was that the vehicle's stereo ranging
perceived the terrain in three dimensions, and it artificial intelligence
planned, without human help, a safe path to its goal.  It was all done within
a power and volume compatible with the onboard resources of a Mars surface
vehicle.  To complete the 100-meter semi-autonomous navigation milestone, the
engineers had to integrate sensing, perception, planning and control into
the self-contained vehicle.

     The long-range technology development goal is to go 20 kilometers, about
13 miles, in one day.  The overall program goals are to develop the
technology to enable planetary surface transportation with unmanned science
and exploration rovers, along with mining and construction vehicles.

     Vehicles such as Robby, but space-qualified and even smarter, would
cross the red, rocky wastes of Mars to find safe paths for future visits
by space-traveling men and women.

     JPL's work is performed in cooperation with NASA's Office of
Aeronautics, Exploration and Technology.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date: 30 Oct 90 04:25:30 GMT
From: ubc-cs!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: You Can't Expect a Space Station to be Cheap

In article <[e-mail]> [e-mail] (Charles Frank Radley) writes:
>Does SSX require RL-10 engines ?   I thought it was aerospike.

Aerospike is a nozzle concept, not a combustion chamber.  The SSX proposal
specified use of RL-10 chambers, and in fact as I recall it did not place
much reliance on the aerospike nozzle.  Hunter seemed to consider it both
unproven (which it is) and relatively unnecessary (maybe).
--
"I don't *want* to be normal!"         | Henry Spencer at U of Toronto Zoology
"Not to worry."                        |  [e-mail]   utzoo!henry

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

Date: 30 Oct 90 14:24:53 GMT
From: thorin!grover![e-mail]  (David Becker)
Subject: Re: A great idea on how to fund NASA!

[e-mail] (david.e.wexelblat) writes:
>I didn't see a smiley on that followup, so:  Hey -- have you ever heard
>of a light-bulb?

Your average incandescent bulb holds slighlty pressurized inert gas.  Glass
that thin could never keep O2 out of vacuum.  The pressure is to keep
the O2 out and the filament burning.

--
David Becker           I Dweam of Dweanie
[e-mail]

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

End of SPACE Digest V12 #515
*******************