Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V15_3/V15NO307.TXT

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Date: Sun, 11 Oct 92 05:02:51
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #307
To: Space Digest Readers
Precedence: bulk


Space Digest                Sun, 11 Oct 92       Volume 15 : Issue 307

Today's Topics:
                       Ariane V.54 / Galaxy VII
               Bootstrap hardware for LunaBase (3 msgs)
                         Mars Observer info?
           Pioneer Venus Update - 10/09/92 (End of Mission)
      Switching ALSEP back on (was Re: another sad anniversary)
                             Telepresence
                        Toshiba vs. Chaparral

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

Date: 11 Oct 92 01:02:55 GMT
From: Dean Adams <[e-mail]>
Subject: Ariane V.54 / Galaxy VII
Newsgroups: rec.video.satellite,sci.space

ARIANESPACE FLIGHT 54

The 54th Ariane launch is scheduled to place the Hughes Communications
GALAXY VII satellite into a geostationary transfer orbit adapted for the
PVA (Perigee Velocity Augmentation) procedure, using an Ariane 42P launch
vehicle equipped with 2 solid strap-on boosters (PAP).  This will be the
3rd flight of an Ariane 4 in the 42P configuration.  It will be launched
from the Ariane launch complex ELA 2, in Kourou -- French Guiana.

The launch vehicle performance requirement for this mission is 3,043 kg
(6,710 lb), of which 2,968 kg (6,545 lb) represents the satellite mass.
The total vehicle mass at liftoff is 323,161 kg.


Required Orbit Characteristics:
  Perigee Altitude ..... 200 km
  Apogee Altitude ...... 27,673 km at injection (prior to PVA)
  Inclination ..........   7 degrees


The Ariane 42P lift-off for Flight 54 is scheduled on Thursday October 15,
1992, as soon as possible within the following launch window:

     Kourou Time       GMT (10/16/92)    Washington, DC
     21:14 - 22:05     00:14 - 01:05     20:14 - 21:05


LAUNCH VEHICLE:

Ariane 42P.  This is a three-stage liquid fueled launcher with solid fueled
strap-on boosters.  The first stage (L220) is built by Aerospatiale, and is
powered by 4 liquid fueled Viking V engines.  The second stage (L33) is built
by MBB Erno and is powered by a single Viking IV engine.  Both the Viking IV
and V engines are manufactured by SEP.  The first and second stages use a
biliquid UH25/N2O4 fuel.  The third stage is built by Aerospatiale and is
the H10 "plus", with larger fuel tanks and increased performance over past
models.  It uses a cryogenic H2/O2 fueled HM-7B engine built by SEP. The two
strap-on boosters (PAP) are built by BPD and use a solid Flexadrine propellant.
The fully assembled launch vehicle stands 54.5 meters high on the pad.
It uses the Ariane Short payload fairing.


Flight Profile:

 +01:31  Solid strap-on booster jettison
 +03:27  First stage separation
 +03:30  Second stage ignition
 +04:35  Fairing jettison
 +05:30  Second stage separation
 +05:43  Third stage ignition
 +18:11  Third stage shutdown / orbit injection
 +20:00  GALAXY VII separation
 +22:46  End of Ariane mission 52


Perigee Velocity Augmentation (PVA):

PVA is a procedure which optimizes the combined performance of launch
vehicle and satellite to increase the on-orbit life of the satellite.
For this mission, the Ariane 42P will lift around 280 kg of additional
satellite propellants, to an apogee of 27,600 km instead of the GTO
apogee of 35,975.  The Galaxy VII satellite will use its apogee motor
at the 3rd and 6th perigee to raise the apogee to the altitude normally
used for circularization of the orbit.

The on-orbit life increase is due to the fact that the satellite apogee
motor does not need to propel the dry Ariane 3rd, which will remain in
the lower orbit of 200 x 22,673 km.  This procedure can only be used by
satellites equipped with a liquid bi-propellant apogee motor (which can
be restarted), and whose tank capacity allows fuel in excess of that
necessary for a standard GTO.  Due to the small inclination of the Ariane
mission (7 degrees), this capacity is often available when the satellites
are built to be launched from sites further away from the equator.
This combination of HS-601/Ariane 42P/PVA allows an increase of more
than one year of orbital life for the commercial use of the satellite.


PAYLOAD:

Galaxy VII is the first satellite with a combined C-band and Ku-band
capability in the Galaxy fleet owned by Hughes Communications.  It is
also the first Arianespace launch of the type HS-601 three-axis stabilized
satellite manufactured by Hughes Aircraft Company.

  Total mass at lift-off .... 2,968 kg
  Mass at GEO insertion ..... 1,680 kg
  Dry mass .................. 1,303 kg
  On-board power ............ 4,700 W (end of life)
  Nominal lifetime .......... 13.5 years
  Span of solar panels ...... 26.5 m
  On-Orbit position ......... 91 degrees west, over the Galapagos Islands.

 Transmission capacity:
   24/30 Ku-band transponders of 50W each.
   24/30 C-band transponders of 16W each.

 In-flight operations:
   Apogee motor ignition for PVA maneuver is at about 24 hrs after launch
   at the 3rd perigee, and about 60 hrs after launch at the 6th perigee.

   First apogee motor firing is at the 12th apogee, about 5 days after
   launch.  Further firing will be done at 14th and 15th apogee.

   Deployment of solar panels .... about 10 days after launch.


LAUNCH COVERAGE:

All Ariane missions are broadcast live via satellite from Kourou. Coverage
begins at 30 minutes before launch and continues until all payloads have
been deployed.  This mission will likely be carried on Galaxy 6, however
it could end up being located on a different satellite such as Galaxy 2.


-{ Dean Adams }-

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

Date: 10 Oct 92 23:37:56 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: Bootstrap hardware for LunaBase
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Nick Szabo) writes:

>More than enough money _where_?  The SEI budget is in the $10's...

Nick, nobody is talking anything about SEI. The question was raised of how
much a particular project would cost. The estimate you give was wildly
in error since you failed to account for the cost effects of a larger market.

Your giveing the cost of the project if it is never executed which is rather
pointless. Even there you are way off base since the cost of an unexecuted
project is $0.00.

If the project where executed, launch costs (among other costs) would be
an order of magnitude lower than you estimate. Any estimate which fails to
account for this was either made by a fool or somebody who just doesn't
understand cost estimating.

I just got done putting together a cost estimate for a project we are bidding
on. If I used your methods of cost estimating, we wouldn't win any contracts.
I therefore very much hope your employer doesn't allow you to estimate
project costs or write proposals.

>Have I finally treaded into the central segment of a mass delusion...

Not a mass delusion, only you deluding yourself.

  Allen
--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves        |
|  [e-mail]     |  nothing undone"                                       |

+----------------------197 DAYS TO FIRST FLIGHT OF DCX----------------------+

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

Date: 11 Oct 92 00:02:46 GMT
From: Henry Spencer <[e-mail]>
Subject: Bootstrap hardware for LunaBase
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Nick Szabo) writes:
>>As Allen pointed out, there's more than enough money there
>>for commercial development of a dozen new launch systems.
>
>More than enough money _where_?  The SEI budget is in the $10's
>of millions.  Commercial funding for moon ventures is zero.

Nick, that's not what we were talking about.  (If you wonder why I usually
ignore your postings, it's because any debate with you seems to be fraught
with these sudden changes of subject whenever you start losing.)  We were
talking about your bloated cost estimates for the projects you don't like.

Nobody will ever quote a hundred billion dollars to launch a moon base (or
whatever) at current launch prices, because a fraction of that amount of
money is enough to build much cheaper launchers.  At the very least, if you
want an *honest* comparison rather than transparently-biased salesmanure
for your own projects, you should discount today's launch prices by a
substantial factor (2 at least, more probably 5 or 10) for economies of
scale in bulk use of existing launchers.  Some sort of allowance for the
development of whole new launch systems would be more realistic, though.
For ten billion, we could fund three SSTO-sized projects at 100% overrun
as far as flight demonstrators, and almost certainly one of them would
work, destroying the entire basis for your cost estimates.

Any combination of irrationality and bloat capable of maintaining prices
despite such an enormous increase in volume would be potent enough to have
similar effects on your favorite projects too.
--
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  [e-mail]  utzoo!henry

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

Date: Sun, 11 Oct 1992 08:11:02 GMT
From: Nick Szabo <[e-mail]>
Subject: Bootstrap hardware for LunaBase
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>In article <[e-mail]> [e-mail] (Nick Szabo) writes:
>
>>More than enough money _where_?  The SEI budget is in the $10's...
>
>Nick, nobody is talking anything about SEI. The question was raised of how
>much a particular project would cost. The estimate you give was wildly
>in error since you failed to account for the cost effects of a larger market.
>

That's strange, we just had a huge thread about SEI's FLO, which
you flamed me for daring to criticize.

It's also interesting that you deleted the second part of that sentence,
which pointed out business investment would not be a source of funds.

(Repeating point that should be obvious for third time in a row, for
Allen's benefit):

The whole point of mentioning SEI's budget is there _isn't_ any
significant market in the political/contracting arena.  That's
what the NASA contractor moon-related work (and ads) are focused on.
There isn't any paying market from the point of view of business, either,
whether the project costs $100 billion or $1,000 billion.  Business just
does not invest in schemes that require multiple layers of new technologies
assumed to be orders of magnitude cheaper than what previous projects
have accomplished.  Any investor with those $$$  will laugh you
right out of their office, unless you've got a juicy NASA contract in your
hand.  It won't matter how many earnest space fans you can gather to
pile on the critics.  If you don't beleive me, try it.  Or at least start
reading what the biz rags like the Economist and Wall Street Journal have
to say about space development. The first thing you will realize is that
selling a commercial project is _very_ different from the traditional skill of
selling the government and government contractors.   They don't care
how popular the project is, and they do care how expensive it is;
almost 180 degrees opposite of governemntal concerns.

Furthermore, your thesis (>volume => <cost) has several exceptions, including
the last magical launch-cost reducer, STS.  The more they tried to increase
STS's launch rate, the more things broke, until they finally went "boom"
with Challenger.   The saddest thing of all is the current SEI and SSTO
strategies are repeating the strategy of the Shuttle -- build something for
astronauts and then start trying to stuff in commercial projects as peripheral
add-ons.  Commerce learned its lesson getting burnt with the STS.
They're not going to take back seat on a NASA project again, unless
NASA is footing the bill.

Finally, the major volume-expanding market already exists, comsats.
But your culture, the NSS lobbyist and NASA contractors, have chosen
to snub comsats, and really commerce and general, as some sort of
hanger-on.   You promote projects like SSTO and SEI that are not
targeted at comsats.  Too bad, because they remain the biggest launcher
market, and the biggest potential customer of lower cost and more reliable
launch services.  It also reveals that your invocation of "commerce"
is just a ruse; you have no serious interesting in _using_ space
except for your own selfish goal, "I wanna go".  You don't realize
that the average businessman can see through that like a fish through
water.

>If the project where executed, launch costs (among other costs) would be
>an order of magnitude lower than you estimate.

Last you were talking it was _two_ orders of magnitude.  Make up your
mind!

(Notice how Allen avoids posting actual numbers, and is quick to flame
those who dare mention costs. That will really impress the investors,
Allen :-)

>Any estimate which fails to
>account for this was either made by a fool

You're right.  I am a fool for repeating over and over the same
common-sense business facts to folks who have their minds made
up, and really couldn't give a damn about business anyway, but
just want to use it to justify the same old failed junk.


--
Nick Szabo                     [e-mail]
Hold Your Nose: vote Republocrat  ////////  Breathe Free: vote Libertarian

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

Date: Sun, 11 Oct 1992 07:17:37 GMT
From: David Knapp <[e-mail]>
Subject: Mars Observer info?
Newsgroups: sci.space,alt.sci.planetary

In article <[e-mail]> [e-mail] (Pat) writes:
>In article <[e-mail]> [e-mail] (David Knapp) writes:
>>
>>Instruments:
>>
>>Gamma Ray Spectrometer; studies surface chemicals/composition
>>Mars Observer Camera; photographs surface
>
>>Thermal Emission Spectrometer; measures IR (I'm guessing primarily surface)
>>Pressure Modulator Infrared Radiometer; measures the atmospheric emission
>>Mars Observer Laser Altimeter; gives higher resolution topographical info
>>Magnetometer/Electron Reflectometer; investigates Martian magnetic fields.
>>
>>
>>The MOC (camera) has <*2* meter resolution! (loud gasp of amazement.) This will
>>allow for detailed study of mass transport over the surface with seasonal
>>variations. (and some very impressive photos indeed.)
>>
>
>
>MO  is currently scheduled only to image mars.  i talked to some
>planetary scientists who were hoping to wheedle some imaging time
>to look at phobos and deimos.  if so,  what are some of the considerations.
>
>i was thinking along the lines of:
>
>    1)  what kind of resolution will they get?
>
>    2) will they be able to image all sides.
>
>    3)  would they be able to use the other instruments as well.
>
>    4) what kind of impact will this have on spacecraft operations.
>    i imagine MO is going to go into a sun synchonous polar orbit,
>    so to get more uniform imaging and keep power levels uniform.
>    would imaging the moonlets, eat up  thruster gas or impede
>    solar collection?
>
>just a few questions.
>
>thanks


The imaging camera is actually only a linear array, sweeping up images
as the planet passes beneath the s/c.

My hunch is that due to geometries of the orbit and the camera, viewing
of moons won't be possible.

--
David Knapp                                      University of Colorado, Boulder
Perpetual Student                                   [e-mail]

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

Date: 11 Oct 92 13:39:24 GMT
From: Ron Baalke <[e-mail]>
Subject: Pioneer Venus Update - 10/09/92 (End of Mission)
Newsgroups: sci.space,sci.astro,alt.sci.planetary

                       PIONEER VENUS STATUS REPORT
                            October 9, 1992
                            End of Mission

     On October 8, 1992 at 12:30 PM PDT, the 70 meter antenna in Goldstone,
California (DSS-14), failed to detect a signal from the Pioneer Venus
spacecraft after periapsis on orbit 5056.  It was assumed that the
either the drag of the atmosphere had knocked the spacecraft's High Gain
Antenna (HGA) off Earth point, or the spacecraft did not survive its last
trip through the upper atmosphere of Venus.  DSS-14 and DSS-43 (70 meter
antenna in Canberra, Australia) continued to search for a signal from the
spacecraft for several more hours, including attempts to acquire a signal
from the forward Omni antenna, but still no signal was detected.
Pioneer Venus end of mission was declared on October 8, 1992 at 17:55 PM PDT
by the Pioneer Project Controller.  The spaceraft's remains will continue
to orbit Venus for a short while, but no data can be collected without a radio
signal.

     Here's a recap of the spacecraft events from the past week:

     October 2 - The sixth altitude raising maneuver was successfully
                 performed and raised the periapsis from 132.9 km to
                 141.7 km.

     October 3 - In an attempt to reorient the spacecraft during apoapsis
                 between orbits 5050 and 5051, Pioneer Venus apparently
                 ran out of fuel. After firing 90 pulses, only a 1 degree of
                 precession was achieved.  The propellant tank pressure
                 dropped by two data numbers to 54.1 psi, indicating that
                 pressurant gas instead of fuel was expelled.

     October 5 - Pioneer Venus was spun up with full thruster response for
                 150 seconds on orbit 5053.  The resultant near-doubling of
                 spin rate will reduce reorientation suffered from drag at
                 periapsis and will facilitate use of the HGA through the
                 next several orbits if the spacecraft survives the deeper
                 penetrations of the atmosphere.  It was also suspected that
                 4 oz of propellant still remained and the spin up would aid
                 in moving the propellant towards the thrusters.

     October 6 - Pioneer Venus survived periapsis on orbit 5054, at an
                 altitude of 130.8 km and a drag of 0.91 m/s.

     October 7 - Pioneer Venus survived periapsis on orbit 5055,
                 at an altitude of 128.9 km and a drag of 1.9 m/s.  Attempts
                 to reorient the spacecraft with thrusters after periapsis
                 was 25% effective.  At 22:25 PM PDT, a pulsed apoapsis
                 manuever of 200 pulses resulted in a gain of 1 kilometer
                 in periapsis altitude.  The tank pressure held at 52.6 psi,
                 indicating that propellant probably still existed.

     October 8 - DSS-14 failed to detect any signal from the spacecraft
                 after periapsis on orbit 5056.  When the signal acquistion
                 continued to be unsuccessful for several more hours, the end
                 of the mission for the Pioneer Venus spacecraft was
                 declared.  The estimated periapsis altitude of the final
                 orbit was 128.0 km, and the final estimated drag was at
                 2.5 m/s.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Einstein's brain is stored
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | in a mason jar in a lab
|_____|/  |_|/       |_____|/                     | in Wichita, Kansas.

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

Date: 7 Oct 92 19:37:27 GMT
From: Marcus Hall <[e-mail]>
Subject: Switching ALSEP back on (was Re: another sad anniversary)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (FRANK NEY) writes:
>>Is there any way to turn ALSEP back on once we get the ground station
>>set up properly?  Or was it a no-return type of prodedure?
>
>Such turnoff procedures are usually irreversible, I believe, to minimize
>the chances of dying hardware later reversing them on its own.  I'm not
>sure about ALSEP in particular.

For what it's worth, on the Kennedy Space center tour, there is a display
with a flight qualified LEM and CM/SM.  The tour guide mentioned that the
landing sites had left instruments on the moon [undoubtedly ALSEP] that
had been switched off but could be switched back on whenever more data
was wanted.

Now, I wouldn't put a lot of faith in this statement, but they did seem to
know alot about what they were talking about on other things.  I only
mention it here for what it's worth...

marcus hall

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

Date: 11 Oct 92 04:48:10 GMT
From: John Roberts <[e-mail]>
Subject: Telepresence
Newsgroups: sci.space

-From: [e-mail] (Gary Coffman)
-Subject: Re: Telepresence
-Date: 10 Oct 92 14:42:41 GMT
-Organization: Gannett Technologies Group

-In article <[e-mail]> [e-mail] (John Roberts) writes:
->
->  Predictive Display for Teleoperation With Delay
->
->  ...The simulator displays a phantom
->  image of the robot superimposed on the delayed "real" monitoring image of
->  the robot. The phantom responds to control signals immediately -- that is,
->  without transmission delay. Its motion predicts that of the real robot.
->  After the transmission delay, the real image of the robot follows the motion
->  of the phantom image.

-After successfully maneuvering the phantom image, the operator sits back
-and watches the delayed image of the rover slowly fall into a subsidence
-hidden from the scan. The screen image is replaced by the words "GAME
-OVER. INSERT $1 BILLION TO PLAY AGAIN"

-Gary

Which is why all the serious Mars rover designs have safety systems built
in - such as the wheel position sensors on Rocky IV, and a few even have
mechanisms to right themselves, such as Go-For.

There are also many envisioned applications of teleoperation which are
*not* rovers. The demonstration project described in the NASA Tech Briefs
article involved a robot arm. I think we all agree that juggling by
teleoperation is going to be a formidable task for a long time. (On the other
hand, some dynamic operations are much simpler - judging from my very limited
experience playing with a time-delay teleoperation demonstrator, the "running
start" bulldozer maneuvers you've described in previous years might actually
be practical.)

It would be interesting to use this feedback system on a rover - the cameras
would be on the rover itself, so the control system would project a phantom
rover in front of you, then as the return signal comes back, the landscape
starts moving, and the phantom rover moves from background to foreground
in the image, approaching the "screen" until it vanishes. (That's for a
long feedback path such as a Mars mission - an experienced operator of a
lunar rover might be able to maintain continuous motion much of the time,
so the phantom would be continually in sight.)

John Roberts
[e-mail]

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

Date: 11 Oct 92 03:42:33 GMT
From: Akmal Khan <[e-mail]>
Subject: Toshiba vs. Chaparral
Newsgroups: rec.video.satellite,sci.space

All the flashy LEDs notwithstanding, can anyone contrast the Toshiba
TRX-80/TRX-100 IRDs with the Chaparral Monterey 70
and the Chaparral  CR110 receivers? Am I making a huge mistake even considering
buying one of these?


        ---- Akmal Khan
             System Software Development
             Silicon Graphics Computer Systems
             [e-mail]

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

End of Space Digest Volume 15 : Issue 307
------------------------------