Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v15_6/v15no603.txt

Internet Message Format | 1993-07-13 | 34KB

Date: Mon, 28 Dec 92 05:09:35
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #603
To: Space Digest Readers
Precedence: bulk


Space Digest                Mon, 28 Dec 92       Volume 15 : Issue 603

Today's Topics:
                       asteroids beyond Jupiter
                          Biosphere 2 update
                      Galileo Update - 12/22/92
                GEO satellites as electrical vehicles
                    Latest Pegasus news? (2 msgs)
                      Magellan Update - 12/21/92
                   Mars Observer Update - 12/22/92
                               Pegasus
   Stupid Shut Cost arguements (was Re: Terminal Velocity (3 msgs)
                       TOPEX Update - 12/22/92

    Welcome to the Space Digest!!  Please send your messages to
    "[e-mail]", and (un)subscription requests of the form
    "Subscribe Space <your name>" to one of these addresses: listserv@uga
    (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle
    (THENET), or [e-mail] (Internet).
----------------------------------------------------------------------

Date: Mon, 28 Dec 92 00:32:34 EST
From: John Roberts <[e-mail]>
Subject: asteroids beyond Jupiter

-From: [e-mail] (Joe Cain)
-Subject: Re: asteroids beyond Jupiter
-Date: 27 Dec 92 18:56:46 GMT
-Organization: Florida State University Geology Dept.

->In article <[e-mail]>,
->[e-mail] (bill nelson) writes:
->> My definition of asteriod is: any body that orginated in the
->> "asteriod belt" (between Mars and Jupiter). etc etc

-    Help! It would be useful to learn what are the "official" uses
-of the words according the IAU (and IUGG?). I have a hard enough time helping
-students try to keep meteor, meteorite, and meteoroid straight when
-there seems to be general disagreement on the distinctions between the
-meaning of the words asteroids, comets and, yes, planets. I posted
-this question recently in sci.astro but so far no one has come to the
-rescue.

I posted a quote from a (1960s-1970s) astronomy textbook last week.
Basically, "asteroid" and "minor planet" are considered synonyms.
The speculation that some comets eventually become covered with tar, dust,
etc. and become icy asteroids has tended to blur the distinction.
Asteroids appear to have a variety of compositions.

-    Is anyone willing to demote Pluto/Charon to asteroid status,
-change Chiron from "asteroid" to comet, buck public sentiment to
-avoid naming a body orbiting mostly a little beyond Pluto "Planet X", or
-think about the use of the term "worlds" that some seem to favor for
-large bodies even if not orbiting the Sun?

Fitting things into definitions is an attempt to simplify one's model of
the universe. I'm not sure that's particularly useful in this situation.
It seems more practical in this case to not take definitions too seriously -
just treat them as a sort of loose and informal classification, and
evaluate individual objects on a case-by-case basis. If you want to be
more formal, you have to divide "asteroid" into at least three categories.

John Roberts
[e-mail]

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

Date: Sun, 27 Dec 92 13:18:52 PST
From: Taber MacCallum <[e-mail]>
Subject: Biosphere 2 update

Biosphere update:
December 27, 1992

First I need to put a disclaimer in here, my posts are
entirely comprised of my biased opinions and do not reflect
in any way Space Biospheres Venture (SBV) policies,
officials or other crew members. Also nobody else at SBV
reads the posts, I write them in my personal free time and
they are written for no other reason.

I have received many more questions than I can
adequately address in the time I have, but the response is
great, thanks, sometimes it is a little rough in here.

The question of why run Biosphere 2 on ambient light is
good and approaches the fundamental question of what
does Bio 2 have to do with space colony designs.

The decision to make Bio 2 open to direct sunlight or
opaque with light pipes or electric light  was a big one early
in design and centered on economics, science, safety,
operation and esthetics. (SBV is a totally private, tax
paying company.)  Making an opaque structure is cheaper
and required no technology development to make air tight.
But the operating cost of electric lights plus the tremendous
added heat load was far to much. Remember that heat
removal in a vacuum or near vacuum is already a big
problem and energy generation in the amounts required to
grow plants using grow lights is problematic. As it is, heat
removal is our biggest energy demand and the largest
single operating cost. The heating/cooling/dehumidification
and filtering system for the air handles a volume equivalent
to the biosphere every 1.5 minutes. A disadvantage of
glass is that if the cooling system failed during a summers
day, the biosphere would over heat in under 20 minutes.
Light pipes depend on the sun as well and cost too much.
Science comes to the rescue, one of the biggest questions
was what are the stability characteristics of a closed
ecological system and how are they effected by changes in
the systems energy flux, so lets tackle this problem right off
the bat. Biosphere would be MUCH easier to operate if
the light input was high and constant, it was a trade off. As
it is, we are operating on greatly reduced light because the
structure blocks out 60% of the photo-active energy. The
diurnal and seasonal oscillations in light provide one of the
most interesting opportunities to study the system. Also
visitors currently provide our main means of attempting to
pay for operating Bio 2 and if it was not possible to see in
from all around, it would stifle tourism. Now people can go
right up to the glass and wave at us. And yes, as needed, a
team of window cleaners go around the outside, dirty glass
can reduce the light transmission by 10 to 20 % very
quickly. Inside we only need to do the bottom two or three
sections of glass in specific areas.

It is probably worth giving some perspective to Biosphere 2
and why it is designed the way it is.

Bio 2 is in a way analogous to the Delta Clipper - X, it
needs to fly after it is built or we don't learn nearly as much
and it is hard to get the money back on a total flop. When
we started the project in '85, I always had to spell
"Biosphere" to people on the phone and people said "what's
that?" now it is a very common word. No closed ecological
systems or even partially-closed ecological systems that
included humans had ever even been seriously paper
studied in the west, much less attempted. The BIOS
projects in Siberia were mostly roomers and no hard data
was available. The projects culminating with BIOS 3, were
comparatively simple, only partially-closed and had some
serious nutrient cycling problems. Our approach was to
take functioning ecosystems as analogs and use them as
the building blocks of a total system. Thus the seven
biomes, an atmosphere, a lithosphere, a water system or
hydrosphere, an information/data and control system and
an energy source are the very basic components of
Biosphere 2, analogous to the Earth. The name Biosphere
2 comes from the idea that it is based on the Earth or
Biosphere 1. The agriculture is operated to maximize food
production which dictates how it is operated, allowing very
little flexibility to make adjustments for changing
atmospheric or energy conditions. The wilderness biomes
have different seasonallity, life strategies, dominant
metabolic pathways etc. which give us allot of flexibility in
managing Bio 2. The desert and Savannah are especially
flexible because dormancy can be controlled by
temperature, humidity and rainfall, allowing us to bring
them into production as needed.

We are trying to learn by doing, we are going to come out
at the end of the first test flight with allot of questions and
a
few answers to problems created by the things we did
wrong. In a way it is a proof-of-concept, that complex
systems can be scaled down dramatically and still work.
This top down approach to stability is in contrast to the idea
that stability is found in simple systems constructed from
the bottom up, individual species by species which is closer
to the NASA approach. Both ways of looking at system
designs are very valid, even though unfortunately
sometimes people fall into separate camps and look
askance at each other. There is allot of cross fertilization
and ultimately the best system will be dictated by the
circumstances and probably be a mix of the two ideas.

One of Biosphere 2's strongest and weakest points, like the
space shuttle, is that it attempts to do many things and in
the process does nothing as well as it could if it had only
one task. Space is by no means the only reason for
Biosphere 2 and in many peoples thoughts it is a very minor
application. With regard to space I hope to come out with
new perspectives on long term space travel and topics
including soil nutrient cycles, atmospheric chemistry,
mission control inside and outside, food production, human
group dynamics, human medical requirements, data
acquisition and control, maintenance and operation of
associated technical systems and waste recycling. The
many functions Biosphere 2 tries and needs to fulfill are
often in conflict with each other, these functions include
ecological research on a global and biome scale, medical
research, profit, education, genetics of small populations,
marine system research, restoration ecology, food web
studies, agriculture, analytical chemistry and spin-offs from
engineering, technology and computer system development
especially in modeling.

The Biosphere 2 project came under allot of pressure to do
ecological research even before the first two year test had
even began. Note that much research was done just to
design Biosphere 2. This happened faster than I and many
other people thought, we were still in design and
construction when the media began asking about our
scientific credibility. To facilitate the research our
scientific review committee (which we had from the very
beginning) recommend among many other things, in a
report made after closure, that we hire a Director of
Science. The report is on the whole very good. Candidates
for the position are being interviewed now and hopefully a
selection will be made by end of January.

For background reading, two recent articles have come out
in the popular literature that are good, The current issue of
Whole Earth Review is excellent and a recent Buzzworm
article is supposedly "more investigative" but they badly
blunder many facts they could have easily checked, plus a
biased slant was put on the article due to PR problems, as
well as the article, Buzzworm carries a regular article by
Linda Leigh, another crew member. Also papers were
given at the last cospar meeting, the proceedings from
which should be out soon. If we wanted to hide what we
were doing, we would not have built Biosphere 2 out of
glass and invited people to see.

The computer data acquisition, control and communication
systems are problematic especially due to software
limitations. One of the main tools for modeling and control
is the General Symbolic "G2" expert system. We use a
distributed broad-band network of 9000 series Hewlett
Packard computers and Sun systems running UX. Each of
which control specific areas of the biosphere using HP
48K I/O systems and independent programmable
controllers run by the computer system. These systems
communicate with dedicated monitoring, data base and
supervisory computers forming a multi level, distributed
system. Reliability of the system is great because when
problems occur the system falls back to the next lower
level. A PC ether network is bridged to the UX system and
fulfills functions like mail, fax, word processing, etc..
Communication and tele-conferencing is also facilitated
with video in and out, picture-tell, video phones, voice mail,
private phone lines and meetings at the glass with an
intercom.

I'll get to the questions on Medical, Hygiene, Insects, CO2
Recycler and Analytical Chemistry in future posts.

A few tidbits, we are now relying heavily on stored animal
fodder from the summer to maintain goat milk production
because the low light has reduced plant growth. Egg
production has stopped because the chickens are molting.
Recent cloudy weather has forced us to put more CO2 into
storage for release in the spring. High CO2 brings the pH
of the ocean to dangerously low levels. Without the ocean
we could go to much higher CO2 levels. The current
average CO2 level is 3700 ppm, oxygen is now at 14.8%.
Living at an equivalent pO2 of approximately 13,000 feet or
96 mmHg has a definite effect on crew performance,
especially in limiting physical exertion and disrupting  sleep
patterns in some crew members. The drug Diamox and/or
concentrated oxygen at low flow rates during sleep helps
relieve the problems in some crew members. We have not
yet seen any marked signs of adaptation to the lowered
pO2 in the physical exams or blood tests.  The holidays
have brought more feasting and we have all put on 1 to 2
Kg of weight!

Cheers and a Happy New Year from Biosphere 2!

Taber MacCallum

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

Date: 28 Dec 92 15:21:35 GMT
From: Ron Baalke <[e-mail]>
Subject: Galileo Update - 12/22/92
Newsgroups: sci.space,sci.astro,alt.sci.planetary

Forwarded from Bill O'Neil, Galileo Project Manager

                            GALILEO STATUS REPORT
                              December 22, 1992

     The Galileo Spacecraft is operating normally in the dual-spin mode and
is transmitting coded telemetry at 1200 bps (bits/second).

     Yesterday, minimal spacecraft activity was scheduled.  Continuous
tracking was scheduled over DSS-14, DSS-43 DSS-61 and DSS-63.

     Today, December 22, 1992, the DDA-5 (Dual Drive Actuator) part A sequence
memory load is being uplinked.  This sequence covers HGA (High Gain Antenna)
warming turn and the motor actuation activities from December 28, 1992 through
January 4, 1993.  Continuous tracking is scheduled over DSS-12, DSS-43 and
DSS-61.

     Over the holiday period, minimal spacecraft activity is scheduled.
Tracking is scheduled over DSS-14, DSS-43, DSS-61 and DSS-63.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Choose a job you love, and
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | you'll never have to work
|_____|/  |_|/       |_____|/                     | a day in your life.

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

Date: Mon, 28 Dec 1992 01:10:31 GMT
From: Bruce Dunn <[e-mail]>
Subject: GEO satellites as electrical vehicles
Newsgroups: sci.space

Regarding Geosynchronous satellites launched from a DC-1


> Allen W. Sherzer writes:
>
>  Maybe you use lower costs to fly redundant satellites, each less relaible.
> When one breaks, it uses a high efficiency electric engine to come back to
> LEO where it is repaired, refueled, and returned. Maybe we abandon comsats
> in GEO and place them in LEO. I can think of lots of alternatives.


        An interesting idea.  Modern comsats have several kilowatts of power,
enough to run an ion or arcjet engine.  An electric engine running off a few
kilowatts has a mass of only a few kg, so could easily be carried on the
vehicle.  The same ion engine could be used for station keeping - all that
would be required is a larger propellant supply to allow for return to LEO.
A major problem would probably be radiation damage due to having to spend
some months in the Van Allen belts as the satellite spirals down to LEO.
This damages solar cells, but if the array is replacable, this might not be
too bad.  Other electronics might have to be replaced because of radiation
damage, but during servicing it might be desirable to replace them anyway for
updating and extension of service life.


--
Bruce Dunn    Vancouver, Canada   [e-mail]

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

Date: Sun, 27 Dec 92 17:19:29 PST
From: Brian Stuart Thorn <[e-mail]>
Subject: Latest Pegasus news?
Newsgroups: sci.space

>We may all be thankful that the people at OSC are willing to try things
>to see if they will work. Left to you, nobody would ever try anything
>since everything which doesn't exist today, in your view, can't be done
>and won't work. Progress is never made by pesismist.
>
>  Allen

   What do you call the TSS tether experiments this summer? Brand new
   technology that could revolutionize orbital transfer and power
   generation. That was those despicable fools at NASA doing this.
   Just because NASA isn't deep in development of a new space booster
   (why bother when SDIO already is) doesn't mean that they aren't
   doing important work. Just about everything they do on the Spacelab
   missions is the (ahem) dull background work needed before going on
   to bigger and better things. It's not fair to denounce NASA for
   laying the foundation while praising OSC and McDAC for erecting the
   skyscrapers.

   -Brian

-------------------------------------------------------------------------
Brian S. Thorn                                    "If ignorance is bliss,
[e-mail]                               this must be heaven."
                                                -Diane Chambers, "Cheers"
-------------------------------------------------------------------------

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

Date: 28 Dec 92 02:17:49 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: Latest Pegasus news?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Brian Stuart Thorn) writes:
>>We may all be thankful that the people at OSC are willing to try things
>>to see if they will work.

>   What do you call the TSS tether experiments this summer?

I call it another example of good research and development we need more of.

>   Brand new technology that could revolutionize orbital transfer and power
>   generation.

Exactly.

>   That was those despicable fools at NASA doing this.

here you lost me. You seem to live in a very black and white world. You
assume that since I don't support everything NASA does (even its mistakes)
that I must oppose everything NASA does.

This is not the case. There is lots of great stuff going on at NASA. I
criticize the unproductive things NASA does so that we can have more of
the good stuff. Why does that bother you so much?

>   Just because NASA isn't deep in development of a new space booster
>   (why bother when SDIO already is)

NASA shouldn't be developing OR operating any operational space transport
system. That is outside its charter and is ultimately wasteful and harmful
to lower cost solutions.

>   doesn't mean that they aren't
>   doing important work. Just about everything they do on the Spacelab
>   missions is the (ahem) dull background work needed before going on
>   to bigger and better things.

Without doubt. The problem is that you seem to think asking the question: "is
there a cheaper way to do this" is treason.

As an engineer I ask myself that same question every single day. Why do you
think NASA shouldn't worry about the costs?

>   It's not fair to denounce NASA for
>   laying the foundation while praising OSC and McDAC for erecting the
>   skyscrapers.

Pegasus is the subject of this thread so that is what I mentioned.

As to denouncing NASA, I praise NASA when they lay the foundation. I
condemn them when they prevent the skyscraper from being built.

   Allen
--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves        |
|  [e-mail]     |  nothing undone"                                       |
+----------------------118 DAYS TO FIRST FLIGHT OF DCX----------------------+

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

Date: Mon, 28 Dec 1992 15:15:15 GMT
From: Ron Baalke <[e-mail]>
Subject: Magellan Update - 12/21/92
Newsgroups: sci.space,sci.astro,alt.sci.planetary

Forwarded from Doug Griffith, Magellan Project Manager

                          MAGELLAN STATUS REPORT
                            December 21, 1992

1.  The Magellan spacecraft continues to operate normally, performing
a starcal (star calibration) and desat (desaturation of the reaction
wheels) in each 3-hour orbit and transmitting a carrier signal (plus
X-band telemetry) which is precisely tracked by the DSN (Deep Space
Network) stations to extract gravity data.

2.  On Sunday, December 20, the spacecraft performed the second radio
science experiment of recent weeks on orbits #6471 and 6472.  As the
spacecraft passed behind Venus (as viewed from Earth), Magellan
performed a limb-tracking maneuver on both ingress and egress.  In
this way, the received signal passed through the atmosphere of Venus
as it was refracted around the limb.

3.  By measuring the attenuation and doppler shift of both the S- and
X-band carrier signals, scientists can study the relative abundances
of H2SO4 (sulfuric acid) and CO2 (carbon dioxide), as well as other
measures of the atmosphere.

4.  Following the radio science experiment, controllers turned on the
360 kHz subcarrier and performed a Very Long Baseline Interferometry
(VLBI) experiment for two orbits.  Then the spacecraft was commanded
back to the carrier plus X-band mode.

5.  Spacecraft temperatures remain in the expected range: Bay 7 is 48
degrees C and Transmitter B is at 51.2 degrees C, with a cycle depth of 1.5
degrees.  The commanded position of the Solar Array Drive Mechanism will
be updated today in preparation for the holiday period.

6.  The spacecraft has completed 6367 orbits of Venus; 731 so far in
Cycle-4, which will end on May 25, 1993.  Cycle-4 is 39.5% complete.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Choose a job you love, and
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | you'll never have to work
|_____|/  |_|/       |_____|/                     | a day in your life.

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

Date: 28 Dec 92 15:29:39 GMT
From: Ron Baalke <[e-mail]>
Subject: Mars Observer Update - 12/22/92
Newsgroups: sci.space,sci.astro,alt.sci.planetary

Forwarded from the Mars Observer Project

                MARS OBSERVER STATUS REPORT
                    December 22, 1992

The C5A sequence continues to clock out and the C5B
sequence is being readied for early January uplink, pending
final confirmation of the date for transition to outer cruise
attitude.

The SCT has successfully loaded the I + 89 star catalogs and
ephemeris updates and the spacecraft is collecting stars while
in the Sun Star Init mode.  The spacecraft will be commanded
back to the  Array Normal Spin mode this afternoon.

The spacecraft is expected to be placed in the outer cruise
configuration in early January, which positions the spacecraft
HGA (High Gain Antenna) and solar array towards earth.  Following
transition to outer cruise, the HGA will be activated.  Following a
short calibration period, the HGA will then be utilized throughout
the rest of the mission for nominal operations.  Until this
transition point, the spacecraft will remain very inactive, with
only star catalog updates planned.

The spacecraft engineering elements and payload instruments
continue to perform well, and within specification.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Choose a job you love, and
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | you'll never have to work
|_____|/  |_|/       |_____|/                     | a day in your life.

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

Date: Mon, 28 Dec 92 00:52:09 EST
From: John Roberts <[e-mail]>
Subject: Pegasus

-From: [e-mail] (Gary Coffman)
-Subject: Re: Latest Pegasus news?
-Date: 27 Dec 92 16:42:47 GMT
-Organization: Destructive Testing Systems

-And to think, it was only last year that Pegasus was the net's darling
-that was going to bring the cost of space travel down to nil. These
-bandwagons are not only crowded, they also seem to be short lived. It's
-funny that the flaws only show up when something actually flies.

You misremember - the attractive features of Pegasus were low cost for a
dedicated mission, and, as a small launcher, being representative of what
startup organizations might use to build up a launcher business.

John Roberts
[e-mail]

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

Date: Sun, 27 Dec 92 17:14:21 PST
From: Brian Stuart Thorn <[e-mail]>
Subject: Stupid Shut Cost arguements (was Re: Terminal Velocity
Newsgroups: sci.space

>A few years ago I saw some figures on the amount of overtime needed to
>process a Shuttle. It was horendous. Adding more Shuttles will just tax
>the groundcrew even more. Adding staff to eliminate this bottleneck will
>only increase costs.
>
  They've gained alot of experience in a few years... like twenty
  more launches under the belt... Overtime has come way down since
  Return-to-flight, but I haven't the figures to offer you proof.

>Your assuming that orbiter availability is the only bottleneck.

  And your assuming they can't do any better than they are now.

>I'm sure they could add one or two flights a year. But so what? all that
>means is that instead of spending three times what we need we are 'only'
>spending 2.75 times what we need to. I don't consider that much of a
>victory.

  You contradict yourself in this paragraph, Allen. A two flights per year
  increase in the 8-per-year schedule is a 25% increase. I can't think of
  any private firm, as you normally cite, which would not want a 25%
  increase in output. Titan and Ariane would be thrilled with it. It could
  make or break DC-1. But for Shuttle its meaningless? Come on...

  You seem to have two sets of measuring systems at work. One which you
  use for DC, Titan, Delta et al, and one which you use for Shuttle.

 -Brian

-------------------------------------------------------------------------
Brian S. Thorn                                    "If ignorance is bliss,
[e-mail]                               this must be heaven."
                                                -Diane Chambers, "Cheers"
-------------------------------------------------------------------------

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

Date: Sun, 27 Dec 92 17:18:51 PST
From: Brian Stuart Thorn <[e-mail]>
Subject: Stupid Shut Cost arguements (was Re: Terminal Velocity
Newsgroups: sci.space

>A few years ago I saw some figures on the amount of overtime needed to
>process a Shuttle. It was horendous. Adding more Shuttles will just tax
>the groundcrew even more. Adding staff to eliminate this bottleneck will
>only increase costs.

 Maybe so, but I don't see the reasoning that NASA can launch monthly
 (assuming they manage it) from December 1992 to April 1993 (five
 launches of three orbiters) but can't keep up that pace throughout
 the year. Does this mean they're pushing hard to get five flights
 off early and then stopping to do alot of postponed maintenance? This
 doesn't seem likely to me. So WHAT IS the reason for the sparse flight
 rate in the second half of 1993? Politics.

>Your assuming that orbiter availability is the only bottleneck.
>I'm sure they could add one or two flights a year. But so what? all that
>means is that instead of spending three times what we need we are 'only'
>spending 2.75 times what we need to. I don't consider that much of a
>victory.

 But you digress. This was not a question of costs but one of performance.
 I doubt anyone at the DC program would be happy knowing that DC-1 was
 flying two or three missions per year less than it was able to. The same
 can be said for Titan, Atlas, Delta, or Ariane. So again you seem to have
 two sets of measuring systems: One for the Shuttle and another for
 everything else.

>>   This is all
>>   moot, since NASA apparently does not want to push its luck prior
>>   to SSF assembly, but it does show that the launch rate is lower
>>   than it could be.
>
>No because those are factors. The bottom line is that NASA cannot fly
>many more missions per year than they are now.

    That's not what you said earlier, Allen. Even you acknowledge one or
    two more flights per year is possible (I say three of four BTW). With
    the current 8 per year, that's a 25% increase. The folks at Titan or
    Atlas would LOVE that.

    -Brian

-------------------------------------------------------------------------
Brian S. Thorn                                    "If ignorance is bliss,
[e-mail]                               this must be heaven."
                                                -Diane Chambers, "Cheers"
-------------------------------------------------------------------------

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

Date: Sun, 27 Dec 92 17:16:09 PST
From: Brian Stuart Thorn <[e-mail]>
Subject: Stupid Shut Cost arguements (was Re: Terminal Velocity
Newsgroups: sci.space

>A few years ago I saw some figures on the amount of overtime needed to
>process a Shuttle. It was horendous. Adding more Shuttles will just tax
>the groundcrew even more. Adding staff to eliminate this bottleneck will
>only increase costs.

 Maybe so, but I don't see the reasoning that NASA can launch monthly
 (assuming they manage it) from December 1992 to April 1993 (five
 launches of three orbiters) but can't keep up that pace throughout
 the year. Does this mean they're pushing hard to get five flights
 off early and then stopping to do alot of postponed maintenance? This
 doesn't seem likely to me. So WHAT IS the reason for the sparse flight
 rate in the second half of 1993? Politics.

>Your assuming that orbiter availability is the only bottleneck.
>I'm sure they could add one or two flights a year. But so what? all that
>means is that instead of spending three times what we need we are 'only'
>spending 2.75 times what we need to. I don't consider that much of a
>victory.

 But you digress. This was not a question of costs but one of performance.
 I doubt anyone at the DC program would be happy knowing that DC-1 was
 flying two or three missions per year less than it was able to. The same
 can be said for Titan, Atlas, Delta, or Ariane. So again you seem to have
 two sets of measuring systems: One for the Shuttle and another for
 everything else.

>>   This is all
>>   moot, since NASA apparently does not want to push its luck prior
>>   to SSF assembly, but it does show that the launch rate is lower
>>   than it could be.
>
>No because those are factors. The bottom line is that NASA cannot fly
>many more missions per year than they are now.

    That's not what you said earlier, Allen. Even you acknowledge one or
    two more flights per year is possible (I say three of four BTW). With
    the current 8 per year, that's a 25% increase. The folks at Titan or
    Atlas would LOVE that.

    -Brian

-------------------------------------------------------------------------
Brian S. Thorn                                    "If ignorance is bliss,
[e-mail]                               this must be heaven."
                                                -Diane Chambers, "Cheers"
-------------------------------------------------------------------------

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

Date: Mon, 28 Dec 1992 15:25:39 GMT
From: Ron Baalke <[e-mail]>
Subject: TOPEX Update - 12/22/92
Newsgroups: sci.space,sci.geo.meteorology

TOPEX/POSEIDON DAILY STATUS
As of:    21 December 1992, 15:00 pm PDT, Monday
UTC:      DOY 356/23:00:00

1.   The satellite and sensors continue to operate nominally and
     the ground system is green.  Tape recorder playbacks were
     received at 100%.

2.   The second Orbit Maintenance Maneuver was performed at
     356/090258 UTC.  Initial indications are that everything
     went well with an overburn of approximately 32 milliseconds
     (0.4%).

3.   The Altimeter experienced a loss of science data on Saturday
     beginning at approximately 0135 UTC.  Engineering data
     continued to be received nominally and no indications of the
     data loss were seen on the ground from the real-time data
     being monitored.  At 1822 UTC, the altimeter experienced an
     SEU that caused the instrument to reset itself.  All data
     has been received nominally since that reset.  Cause of the
     data loss is under investigation, an SEU is thought to be a
     likely culprit.

4.   The satellite was switched from V/T Power Level 3 to V/T
     Power Level 4 this morning.  All indications are normal for
     this switch.

5.   New bias quaternion values are being sent to the satellite
     tomorrow.  These values will change the bias in the roll
     axis only (from -.11x to -.015x).  The bias in the pitch
     axis will remain unchanged at +.15x.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Choose a job you love, and
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | you'll never have to work
|_____|/  |_|/       |_____|/                     | a day in your life.

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

End of Space Digest Volume 15 : Issue 603
------------------------------