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Subject: SPACE Digest V11 #80

SPACE Digest                                      Volume 11 : Issue 80

Today's Topics:
           Payload Summary for 02/23/90 (Forwarded)
       Re: Did SEASAT See More Than It Was Supposed To?
      Re: Fun Space Fact #1: Launcher Development Costs
       Re: Fun Space Fact #1: Launcher Development Costs (long)
        Re: New private home satellite network
                   Beanpole
     NASA technicians begin removing LDEF experiments (Forwarded)
----------------------------------------------------------------------

Date: 23 Feb 90 21:01:02 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Payload Summary for 02/23/90 (Forwarded)


                                 Payload Status Report
                                 Friday, February 23, 1990


          George H. Diller
          Kennedy Space Center
          NASA PA-PIB


          HUBBLE SPACE TELESCOPE

               Prelaunch functional testing of the Hubble Space Telescope
          in the Vertical Processing Facility at KSC was completed on Feb.
          17.  The telescope is being powered up again from time to time to
          reverify test data.  A retest of the Faint Object Camera was
          performed on Feb. 22.  The spacecraft will also be powered up to
          test the flight batteries after their installation.

               HST closeout operations began on Feb. 15.  This work
          includes removal of nonflight items, closeout of the solar
          arrays, configuration of the high gain antenna in preparation for
          installation into the payload canister, and installation of the
          flight batteries.  A final cleaning of the telescope is scheduled
          for next week.  To further assure cleanliness, the cocoon--a
          protective sanitary liner over the spacecraft--will be changed.

               Upcoming schedule milestones include the installation of
          flight batteries on Mar. 16, HST installation into the payload
          canister on Mar. 23,  move to the launch pad on Mar. 26, and
          installation of the telescope into the payload bay of Discovery
          on Mar. 29.  The launch of the Hubble Space Telescope is
          scheduled for Apr. 12, with the launch window opening at
          9:21 a.m. EDT.



          GAMMA RAY OBSERVATORY

               Repairs on the insulation of the Energetic Gamma Ray
          Experiment Telescope (EGRET), as a result of moisture from the
          shipping container, was completed this week. One square foot of
          silvered teflon and aluminized capton was replaced.  Next week,
          the other affected surfaces will cleaned with alcohol which will
          be acceptable for flight.

               Work has been underway this week to install two electronics
          boxes which are elements of the spacecraft's command processing
          chain.  This will be completed early next week.

               The routine leak check of the orbit adjust thrusters has
          been conducted.  Today, one of the thrusters is being test cycled
          for further leakage evaluation.

               Also checked this week as planned was the crystal of the
          Total Absorption Shower Counter which must be examined
          periodically for evidence of moisture.

               The six solar cells which were cracked during installation
          of the solar array cover prior to shipping have been replaced.
          The cover glass is being installed today.  There are
          approximately 3,200 solar cells on each panel and there are eight
          panels on the spacecraft.

               The spacecraft is scheduled to be powered up for the first
          time at KSC on Monday, Feb. 26, to start the scheduled series of
          functional tests.




          DELTA ROSAT

               The ROSAT spacecraft arrived at Cape Canaveral Air Force
          Station at 3:30 p.m. on Feb. 20, shipped from Munich, West
          Germany, aboard a German 747 cargo plane.  The spacecraft in its
          transporation cansiter is now in the airlock of Hangar AE for
          cleaning before moving it into the white room on Monday for its
          unpacking and placement in a test stand.

               The Delta II launch vehicle is on Cape Canaveral Air Force
          Station and will be taken to Launch Complex 17 on March 28.  The
          solid rocket boosters will be erected during the period from
          March 29 to April 5.  The second stage will be mated to the first
          stage April 6.

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

Date: 23 Feb 90 17:56:43 GMT
From: zaphod.mps.ohio-state.edu!uwm.edu!cs.utexas.edu!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Did SEASAT See More Than It Was Supposed To?

In article <[e-mail]> [e-mail] (Nick Watkins) writes:
>1) Where can we find a picture showing these seabed features?

Look at almost any good source for science coverage -- Scientific American,
for example -- in 1978 or shortly thereafter.  There was some small fuss
about the unexpected visibility of bottom features.  Sorry I can't provide
a more specific reference, but remote sensing hasn't been a major interest
of mine, and the three or four books I have on it are all optical-only, no
radar.

>2) There have been rumours (e.g. a piece by Nicholas Booth in, I think,
>the British "Sunday Correspondent") saying that SEASAT did not fail but
>was killed as a result of the DoD exercising its prerogative. Is this
>just paranoia or is it likely to have any basis in fact?

I haven't heard anything I would call evidence for this.  It strikes me
as implausible that it could stay secret for over a decade, especially
since I don't think DoD has any "prerogative" over civilian research
satellites.

It *is* interesting that the Shuttle Imaging Radar experiment has flown
twice (I think) but all the images that I recall seeing from it have been
from land areas.  One wonders who had input into the coverage planning.

>3)If SEASAT worked so well, why was the Navy Clipper Bow project phased out?
>Does Lacrosse do naval imaging also? And, was the resolution of SEASAT
><, >, or = to that of the Russian RORSATS?

Good questions; the answers are probably classified. :-)  On the last, as
far as I know the Soviet radarsats are not doing synthetic-aperture radar
imaging at all.  Their purpose is to spot surface vessels, which is orders
of magnitude easier.
--
"The N in NFS stands for Not, |     Henry Spencer at U of Toronto Zoology
or Need, or perhaps Nightmare"| uunet!attcan!utzoo!henry [e-mail]

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

Date: 23 Feb 90 11:47:29 GMT
From: mcsun!ukc!icdoc!syma![e-mail]  (Nick Watkins)
Subject: Re: Fun Space Fact #1: Launcher Development Costs

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Nick Watkins) writes:
>>See a recent issue of The Scientist (22 Jan 90) for the latest on Roger
>>Boisjoly, and the price he has paid.

>But before you weep too hard for him, read the Rogers Commission report,
>noticing what he did and didn't (mostly didn't) do at the time.  He's
>gotten the shaft not for trying to stop the launch -- he didn't try hard --
>but for talking too much to the investigators afterwards.

I *did* read it (Vol 1 anyway, to which I assume you refer), obviously I
need to read it again. However, a system in
which people are penalised for honesty (even if only after the fact)
does not augur well for the future of NASA or the contractors, at least
in terms of achieving the goals you'd like to see them achieve. There is
also the relatively benign nature of the commission, in which all but
Feynman and Rogers had direct aerospace connections, if I recall
correctly. If talking to these is "grassing", well ... ( I grant that the
press is another story.)

On a related point, Feynman's memoirs suggest that Donald Kutyna (USAF
general) put him onto the trail of the solid booster problem. Is there a
feeling that the USAF knew, but just needed the commision to confirm it?
If so, was the report's conclusion  ideal for their purposes, leaving
the Shuttle as usable but no future threat. Feynman drops hints, but
never makes it explicit.

Nick





--
Nick Watkins, Space & Plasma Physics Group, School of Mathematical
& Physical Sciences, Univ. of Sussex, Brighton, E.Sussex, BN1 9QH, ENGLAND
JANET: [e-mail]   BITNET: [e-mail]

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

Date: 23 Feb 90 19:17:58 GMT
From: snorkelwacker!usc!cs.utexas.edu!jarvis.csri.toronto.edu!csri.toronto.edu![e-mail]  (John Hogg)
Subject: Re: Fun Space Fact #1: Launcher Development Costs (long)

In article <[e-mail]> [e-mail] (Todd Johnson) writes:
>In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>>I dimly recall a design sketch from Jordin Kare's group for a laser
>>launcher costing about half a billion dollars that could launch more
>>than the entire shuttle fleet, for that matter.
>
>Henry, what were the anticipated spacecraft loads with the laser
>launcher? Very high g loads would require a greater structural
>mass although this trades off against lower launch costs. At
>some point it gets more expensive to use a high g launcher than
>even the Shuttle.

I don't know what the latest figures are (why don't you ask Kare
himself?) but from the Proceedings of the SDIO/DARPA Workshop on Laser
Propulsion in July '86, we have:

    Initial Mass: 1000 kg
    Final Mass: 136 kg
    Peak Acceleration: 5.6 g
    Laser Power: 100 MW

Graphs of cost estimates are also given.  The cases considered are a 1
GW laser launching 1-ton payloads, and a 100 MW laser launching 200 lb
payloads; each is plotted assuming a dedicated laser, and use of a
laser built for other purposes.  The 1 GW, dedicated version is more
expensive than the shuttle at shuttle payload-to-orbit-per-year rates,
since the capital cost of the laser dominates.  However, at higher
launch rates, the cost of electricity becomes the limiting factor.  A
dedicated laser bottoms out at about $150/lb to LEO (all figures 1986
$US), and this falls below $100/lb if the laser can be rented from a
convenient defender of the free world.  At that cost, the big laser is
sending up 64 000 tons/year.  Reread that sentence, and think about
what would (and would not) pay at that volume and price.  Hint: think
of it as $200 000 for *every* ton, including the lowest-value ones.

The costs given in this four-year-old workshop still exceed half a
billion of anybody's dollars: the estimate used was $10/W for laser and
optics, which means that the smaller proposed version still runs $1G
for these items alone.  For the 6 kg payloads that were mentioned in an
earlier note, though, I suppose that something cheaper could be worked
out.  And the proposal used a capital cost of 20%/year; that is, the
up-front expenditure was amortized over five years.  This makes the
financial situation much more reasonable.

Quick summary: lasers looks very good if a *lot* of small payloads need
launching.  Small need not mean tiny.  Small numbers of large payloads
are still more cost-effectively sent up by rocket.

---
John Hogg            [e-mail]
Department of Computer Science, University of Toronto

4-P vehicle:        ``Let's leave everything on the ground except
(Kantrowitz, 1986)        Payload, Propellant, and Photons, Period.''

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

Date: 23 Feb 90 17:16:52 GMT
From: mcsun!ukc!edcastle![e-mail]  (Bob Gray)
Subject: Re: New private home satellite network

In article <[e-mail]> [e-mail] (Gary Hughes - VMS Development) writes:
>In article <[e-mail]>, [e-mail] (Brad Templeton) writes...
>>What if a private concern, based on some lax-law island, were to get
>>together $300 million an launch one of these things?   They could start
>>completely uncensored, unregulated TV -- assuming they got somebody
>>(the Chinese?) to launch it.

>In a sense this has already happened, with Rupert Murdoch's DBS plans for the
>UK. This will use Astra and is therefore not under control of the UK
>broadcasting authorities. Rupert has promised to be a good boy.

Nothing to do with Rupert Murdoch.

Murdoch's SKY company leases some of the transponders on
the Astra DBS satellite. Other European companies use other
transponders to broadcast other channels to other parts of
Europe.

In particular, one channel carries material of a more adult
and sexualy explicit nature. This sort of channel is
perfectly legal in both Luxembourg where the satellite is
fed and controlled from, and in the Netherlands, which is
where the main audience is.

When the usual "moral watchdogs" in the UK learned that ordinary
SKY satellite dishes could be used to recieve this channel in
the UK, they had a collective fit.

The people who operate the channel can't understand what the
problem is. They have however started to encrypt the signal.

The Government is considering banning posession of the
decoders needed to decode the cannel, and making it an
offence to have any business dealings with any of the
companies involved. They can't think of anything else that
they can do to stop people watching.

Sales of SKY satellite dishes are said to be booming.

>Interestingly, Murdoch was part of the Sky Cable announcement, as was Hughes
>Communication. My guess is that it will be considered a US domestic comsat,
>subject to US law.

But suppose a company in a south American country started
broadcasting to Mexico from an International DBS satellite?
No US citizens involved, no laws in either country broken,
but that the broadcast could be picked up with a $200
satellite reciever dish. Further suppose that the content of
the broadcast offended the self appointed guardians of
morality. What could they do, apart from sending in the troops?
    Bob.

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

Date: 24 Feb 90 06:53:19 GMT
From: mephisto!prism![e-mail]  (Daniel Rothman)
Subject: Beanpole

Has anybody out there heard rumors of a beanpole [ie an earthbound structure
extending to low orbits]?  A friend of mine in polymers mentioned that new
ceramics could possibly withstand the shearing loads on such a structure.

Have there been any conferences/papers/references on the topic?

Thanks all, and apologies if this is a repeat...

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

Date: 23 Feb 90 20:54:23 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA technicians begin removing LDEF experiments (Forwarded)


  Patricia E. Phillips                          Feb. 23, l990
  Kennedy Space Center, FL.

  Jean Drummond Clough
  Langley Research Center, Hampton, Va.

  KSC Release No. 30-90

  NASA TECHNICIANS BEGIN REMOVING LDEF EXPERIMENTS

       NASA technicians from Langley Research Center began removing
  experiments  today  from  the  Long  Duration  Exposure  Facility
  (LDEF),  the satellite retrieved from space by the STS-32 crew in
  January.

       The first experiment, the Space Exposed Experiment Developed
  for Students (SEEDS),  was removed from the spacecraft  at  12:22
  p.m.  EST. SEEDS, sponsored by the George W. Park Seed Company in
  Greenwood, S.C.,  will eventually go to classroom students around
  the country for use in school science projects.

    Processing  plans call for the removal of three other trays
  today.  Illustrating the international flavor of the experiments,
  two of these trays contain cosmic ray experiments from the Dublin
  Institute for Advanced Studies in Dublin, Ireland. The other tray
  scheduled  for  removal  today is a Langley Research Center space
  debris experiment.

       The protocol for tray removal is painstaking in its  protec-
  tion  of scientific data.  As each tray is removed from LDEF,  it
  will be placed on a workbench where  the  principal  investigator
  will  perform  closer  inspections  and  take basic measurements.
  These  measurements  will  include   detailing   the   sizes   of
  micrometeoroid and orbital debris impacts.

       The  combined  data from individual trays and the LDEF frame
  will provide valuable information in planning future space struc-
  tures, including Space Station Freedom. Removal of the 57 experi-
  ments,  contained in 86 trays mounted on the LDEF  framework,  is
  expected to continue through March.

       After the measurements and first analyses are completed, the
  experiment   hardware   will   be  appropriately  configured  for
  transport,  then  packaged  and  shipped  to  the  investigator's
  laboratory.  There, additional investigation and analysis will be
  performed.  More than 200 investigators have participated in  the
  experiments flown on LDEF, which spent almost six years in space.

       Preliminary  results of these individual investigations will
  be announced late this  summer  during  an  Investigator  Working
  Group meeting to be held at the Langley Research Center, Hampton,
  Va.  Langley  developed  and  managed the LDEF project,  which is
  unique in its opportunities for analysis of the effects of  space
  on various materials.

       The date of the conference will be announced later.

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

End of SPACE Digest V11 #80
*******************