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Date: Fri, 13 Jul 1990 02:17:09 -0400 (EDT)
Subject: SPACE Digest V12 #59

SPACE Digest                                      Volume 12 : Issue 59

Today's Topics:
              Re: man-rated expendables
             Re: Bush Approves Cape York
    Re: Oppose manned Mars exploration -- support robotics
              Re: man-rated expendables
               Re: NASA Budget
             Re: Bush Approves Cape York
             Re: Bush Approves Cape York
               Personnel Launch System
              Voyager Update - 07/12/90

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

Date: 12 Jul 90 17:28:11 GMT
From: mojo![e-mail]  (Doug Mohney)
Subject: Re: man-rated expendables

In article <[e-mail]>, [e-mail] (George William Herbert) writes:
>In article <[e-mail]> [e-mail] (Doug Mohney) writes:
>>And you'll look like hamburger if anything goes wrong....me thinks I'll wait
>>til the successors of the X-30 go up.
>
>In that case, meet you there...I ought to have a decade on-orbit experience
>by then 8-)

Riiight....it's your life. You'd better call Lloyd's of London; nobody else
is going to write insurance for you.

>[ps- it ought to be safer than the shuttle is; it has 2 less big engines (if
>you think the ssme's are safe, go check again) and no joints.]

>  == George William Herbert  ==   "Well, if an outraged Canadian terrorist was
> == JOAT for Hire: Anything,  ==  *** to come down and assasinate Quayle, what
>=======Anywhere, My Price.======= ****** would happen?" -history prof _trying_
> ==   [e-mail]    ==  ************* to explain why WW I started...
                                                ^
                        | Celebration in the streets?

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

Date: 12 Jul 90 21:36:14 GMT
From: mojo![e-mail]  (Doug Mohney)
Subject: Re: Bush Approves Cape York

In article <[e-mail]>, [e-mail] (Matthew DeLuca) writes:
>
>I'll answer this one, too.  Since spysats are in vaguely polar (or the
>closest they can get, if launched from the shuttle) orbits, they spend
>half their time over the Southern Hemisphere.  God knows what they're
>going to look at down there, though. :)

Scheming penguins and great white sharks....

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

Date: 12 Jul 90 14:50:13 GMT
From: cs.utexas.edu!know!samsung!noose.ecn.purdue.edu!mentor.cc.purdue.edu!l.cc.purdue.edu![e-mail]  (Herman Rubin)
Subject: Re: Oppose manned Mars exploration -- support robotics

In article <[e-mail]>, [e-mail] (T. Joseph Lazio, Cornell University) writes:
> In article <[e-mail]>, [e-mail] writes:
< > In article <[e-mail]> [e-mail] (Philip C. Plait) writes:
< >>In article <[e-mail]> [e-mail] (Russ Cage) writes:
< >>>In article <[e-mail]> [e-mail] (David Rabson) writes:

            ........................

< >>>Robots cannot do anything near what human beings can.  Remember that.
< >>
< >>I disagree. Robots can and have gone to every planet in the solar system
< >>except for Pluto. We as humans (and Americans!) lack the knowhow to get
< >>a man back to the Moon in less than 10 - 15 years.
< >>
< > Perhaps, but you miss the point.  Robots do not have the ability to react to
< > the *unexpected* that might be encountered on such a mission.  They have only
< > minimal interpretive abilities, and no real creativity (no real AI yet).
>
>    What do you mean by *observational* smarts?  We can produce robots
>    which have instruments to observe from the radio to the UV.  Humans
>    are remarkably limited outside the visual and even within this limited
>    range, are not that good at providing hard data.
>
>    Robots do have the ability to react to the unexpected, thanks to
>    human controllers on the ground.  Further, I think that if you
>    examine the record, particularly of Voyager, you will see that most
>    things to which the probes had to react were equipment failures.
>    While it is easy to reroute instructions or shut down instruments,
>    it is a bit more difficult to shut down life support.

This is where the time problem comes in.  The problems of Voyager were not
so urgent that a 5 hour interval between noticing the problem and correcting
it was of importance.  If Voyager had detected a rock which would hit it in
one hour and destroy it, well, that's all, folks.

>    Perhaps now would be a good time to ask the oceanographers how they
>    explore the ocean bottoms.  After all, the bottom of the ocean is
>    a hostile environment to humans, admittedly in somewhat different aspects
>    than outer space but hostile nonetheless.

The round-trip communications time to the sea bottom is a small fraction of
a second.  The round-trip time to the moon is about 2.5 seconds.  The round
trip time to Mars is on the order of 10-30 minutes.

A man controlling a robot on the sea bottom can completely ignore the time
factor.  Simulations have shown that humans can adjust to the time factor on
the moon, but still real caution is needed.  If people had such slow reaction
times on earth, it would be difficult to control automobiles at speeds of
greater than 10 MPH.  With a 10-minute delay, that boulder has crushed the
robot before it can move out of the way.

--
Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907
Phone: [phone]
[e-mail] (Internet, bitnet)    {purdue,pur-ee}!l.cc!cik(UUCP)

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

Date: 12 Jul 90 17:40:37 GMT
From: usc!samsung!uakari.primate.wisc.edu!uflorida!rex!rouge![e-mail]  (Fraering Philip)
Subject: Re: man-rated expendables

In article <[e-mail]> [e-mail] (Doug Mohney) writes:

DM>A) It's not SRB powered, B) It'll have an ejection seat C) It's more likely to
DM>be able to "fly back" in some way, shape, or fashion in the event of bad
DM>things happening.  You lose power in Pegasus, you drop like a rock. You lose
DM>power in the X-30, you'll slow down and become a glider.

How good a glider, I wonder? Will its L/D ratio be good enough to get
back to a runway? Will they have to wait for excellent weather at several
different possible abort sites, including ones they probrably can't abort
to anyway (Kennedy) before taking off?

Phil

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

Date: 12 Jul 90 20:22:13 GMT
From: ox.com!itivax!vax3.iti.org![e-mail]  (Allen W. Sherzer)
Subject: Re: NASA Budget

In article <[e-mail]> [e-mail] (Dan Sullivan) writes:
>
>>all of this could be paid for with the money saved from ...
>
>This and comments like it assume that the 'congresscritters' (I love that
>expression, it fits mine perfectly) can't find some other place to spend
>it and would allow NASA to keep it.

No this is not correct because we pay for this out of tax money. Let's say
we do it and Congress cuts the $1.5B per year out of the budget. We have
still paid for it in the sense that we now are more productive. I guess
I mean that the ROI is very good for this proposal.

         Allen
|                          |      In War: Resolution                      |
| Allen W. Sherzer         |      In Defeat: Defiance                     |
|   [e-mail]            |      In Victory: Magnanimity                 |
|                          |      In Peace: Good Will                     |

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

Date: 12 Jul 90 00:51:19 GMT
From: sdd.hp.com!samsung!munnari.oz.au!metro!wolfen!wyvern![e-mail]  (Rev Phil Skinque, DD (Ret.))
Subject: Re: Bush Approves Cape York

In article <[e-mail]> [e-mail]
 (Doug Mohney) writes:
>In article <[e-mail]>, [e-mail] (Gregory
> N. Bond) writes:
>>
>>U.S.) will have to pay like anyone else.  And there is _NO_ role in
>>space for the Australian military.
>
>I guess they wouldn't want to put up a com-sat or an observation sat (spy
>sat just doesn't fit the Aussie frame of mind), huh?

They probably couldn't afford one. We're a huge country with a tiny
population. We have an enormous coastline to watch, but mostly the
watching is done by the customs service. Other than that, we can always
acquire elint from our allies the USA (whom you will recall have a
number of satellite bases here).


-- Phil.

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

Date: 12 Jul 90 18:19:36 GMT
From: swrinde!cs.utexas.edu!mailrus!uflorida!mephisto!prism![e-mail]  (Matthew DeLuca)
Subject: Re: Bush Approves Cape York

In article <[e-mail]> [e-mail] (Doug Mohney) writes:
[Referring to using U.S. spooksats for the Aussies...]

>Somehow, I don't think the U.S. would bend over backward to run a KH-11/12
>mission in your part of the world unless it was REALLY needed. Most of the
>coverage is (probably, but Henry will correct me, of course) in the Northern
>Hemisphere.

Actually, since the 'F' key is still warm from my previous followup,
I'll answer this one, too.  Since spysats are in vaguely polar (or the
closest they can get, if launched from the shuttle) orbits, they spend
half their time over the Southern Hemisphere.  God knows what they're
going to look at down there, though. :)



--
Matthew DeLuca
Georgia Institute of Technology      Do not meddle in the affairs of wizards,
Office of Information Technology     for they are subtle, and quick to anger.
Internet: [e-mail]

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

Date: Thu, 12 Jul 90 14:43:16 PDT
From: Edmund Hack <[e-mail]>
X-Vmsmail-To: AMES::"[e-mail]"
X-Vmsmail-Cc: ONEIL
Subject: Personnel Launch System

There has been much discussion on sci.space about the need for a low
cost system for sending crews up to space station so that a full
shuttle mission is not used for that.  Well, despite what has been posted,
NASA has been looking at such a system for over a year.  In March
1989, a study was started by the Office of Space Flight to find an
approach for staff deliveries to Freedom that did not use the shuttle,
a system called the Personnel Launch System (PLS).

The idea is to have a vehicle to deliver 8 persons to LEO with
limited cargo, using an expendable booster and preferably landing on
dry land.  Two major design priorities were placed on the team: safety
and life-cycle efficiency.  At the Johnson Space Center, this has
translated into existing technology use and no wings.  Boeing Aerospace
is doing support work to NASA/JSC.  Marshall Space Flight Center is
doing work on booster concepts (Titan 4 class vehicle).  Kennedy is
looking at vehicle processing and launch systems.  Langley is looking
at a lifting body capsule design with fins.  At JSC, support for the
team is also coming from Engineering, Mission Ops (i.e. flight
controllers and mission planners) and Flight Crew Ops (i.e.
astronauts).  A zero assumptions base is being used to allow any new
idea to be considered and to challenge existing ways of doing things.
The current design being modeled and studied at JSC is a biconic
design (it looks like a cross between the nose of a 707 and a Gemini
capsule).  This gives a good payload volume and a good shape for an
airlock/service module attachment.  The team got some members from
early work on the Assured Crew Return Vehicle study group, who had
researched the NASA archives for data on capsule design lessons from
Apollo and Gemini.  In addition, the team leader had been involved in
Shuttle "lessons learned" studies and meetings.

The PLS is expected to have 12 or so vehicles and a 20 year lifetime.
It is felt that having a large number of vehicles will reduce the
round-the-clock vehicle processing pressures that are present in the
Shuttle fleet of 3 vehicles.  The PLS will have an Apollo-style escape
system leading to a water landing on parachute.  Nominal launch will
be 3-4 gs, with a short 8 g period during an abort.

A typical mission will be 2-3 days long (i.e. Freedom crew rotation).
A small cargo area for personal gear is included (you know, CDs, twinkies,
videotapes, pictures from home....).  It would also be possible to
carry small high-value cargoes by reducing the number of passengers.
The reference design has 8 passengers and 2 crew with major automation
of flight systems and ground systems.  The PLS will land at KSC using
a gliding parachute (3 stage parafoil) and landing on rear end airbags
and a surfboard size nose skid.  The PLS has 2 parts - a systems
module with propulsion, power and other systems and a personnel
module.  They unbolt so the systems module can be worked on in a
hazardous materials facility and the personnel module in a shirtsleeve
facility.  Current schedule calls for PLS to be available in 10 years,
but the schedule could be greatly speeded up.

This information paraphrased from the JSC newspaper "Space News Roundup"
of 7/6/90.  In addition to this project, I have heard of a separate group
looking at using expendables for logistics deliveries to Freedom.  Two
reference missions are being looked at - routine scheduled deliveries
(air, food, etc.) and emergency deliveries of small payloads, with separate
launchers for each.

Edmund Hack
Lockheed ESC
[e-mail]

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

Date: 12 Jul 90 21:28:51 GMT
From: usc!elroy.jpl.nasa.gov!forsight!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Voyager Update - 07/12/90


                     Voyager Mission Status Report
                            July 12, 1990

                              Voyager 1

     The Voyager 1 spacecraft continues its routine collection of cruise
science data.  One frame of high rate Plasma Wave (PWS) data was recorded
on 7/3.  High rate Ultraviolet Spectrometer (UVS) observations of HR 264
and HD 19832 were conducted on June 29 and July 3 respectively.  Spacecraft
and Deep Space Network (DSN) performance was nominal for the observation.

     On June 29 full Attitude and Articulation Control Subsystem (AACS),
Computer Command Subsystem (CCS), and Flight Data Subsystem (FDS) memory
readouts were executed on the spacecraft.  Memory compares have been
requested and received which indicate that the memory contents for each
subsystem memory are as expected.


                              Voyager 2

     The Voyager 2 spacecraft also continues its routine collection of
cruise science data.  One frame of high rate PWS data was recorded on
July 3.  UVS observations of Feige 7 and Delta Ceti were made while in
UV-5A data mode.  The five glimpses into the data quality during the week
indicated that everything seems to be going well.

     The UV-5A Planetary Radio Astronomy (PRA) and PWS data appeared nominal.
However, the status words for PRA are still incorrect even though the software
shows the correct values are present.


                  CONSUMABLE STATUS AS OF 7/12/90

    P R O P E L L A N T    S T A T U S          P O W E R

                     Consumption
             One Week    Propellant Remaining     Output     Margin
  Spacecraft  (Gm)                (Kg)            Watts      Watts

   Voyager 1    5             36.4 + 2.0          370         55
   Voyager 2    6             39.5 + 2.0          373         66

      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

End of SPACE Digest V12 #59
*******************