Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_1/V11_194.TXT

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Subject: SPACE Digest V11 #194

SPACE Digest                                     Volume 11 : Issue 194

Today's Topics:
         NASA Headline News for 03/27/90 (Forwarded)
         NASA Headline News for 03/28/90 (Forwarded)
     Re: Coilgun on a 747 - supplies to orbit at $20/lb?
       Re: Did SEASAT See More Than It Was Supposed To?
              Intelsat Recovery (2 of 3)
      Re: Discovery's Spin in 2010 (Was Re: Artificial gravity)
----------------------------------------------------------------------

Date: 28 Mar 90 09:16:48 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 03/27/90 (Forwarded)

-----------------------------------------------------------------
Tuesday, March 27, 1990                       Audio: 202/755-1788
-----------------------------------------------------------------

This is NASA Headline News for Tuesday, March 27, 1990.


Installation of the Hubble Space Telescope into the orbiter
Discovery's payload bay has been delayed at Kennedy Space Center
for 24-hours.  Technicians are working to rid the Payload
Changeout Room of midges, an insect that looks like a mosquito.
By this morning about 30 of the tiny insects had been caught in
special traps set up in the Changeout Room.  The midges were on
the orbiter's payload bay doors when the Rotating Service
Structure was retracted to receive the telescope Sunday.  The
protective cocoon remains around the telescope until tonight.
Transfer to the orbiter is now expected Wedneday beginning at
8:00 A.M., Eastern time.

Meanwhile, a partial leak test was successfully run on the
orbiter's liquid hydrogen system yesterday following the
replacement of a seal on a joint between the engine number 2 fuel
turbopump and the main engine.

Discovery will be using new carbon brakes during the landing of
the STS-31 mission.  The new system will be tested during the
landing on the dry lake bed at Edward Air force Base by an array
of instruments on Discovery.  The installation of carbon brakes
is one of a number of steps necessary to land orbiters again at
Kennedy Space Center.

Space Shuttle managers meet this Friday to conduct the Flight
Readiness Review for the April 12 launch.



Langley Research Center technicians will finish removing
experiment trays from the Long Duration Exposure Facility this
week.   Once all the trays are removed and shipped to principal
investigators, a detailed close inspection and photo survey of
the spacecraft's structural elements will begin.



Aviation Week magazine reports a key member of Congress says NASA
should prepare to trim its fiscal 91 budget request by $1.1 to
1.5 billion.   Representative Bob Traxler, chairman of the House
Appropriations subcommittee for NASA, indicated he's doubtful the
agency will gets its requested 23-percent increase.  The
publication added Traxler was also pessimistic about NASA getting
an okay for multi-year space station funding.


                       * * * * * * * * *







-----------------------------------------------------------------
Here's the broadcast schedule for public affairs events on NASA
Select TV.  All times are Eastern.


Thursday, March 29.....

      11:30 A.M.       NASA Update will be transmitted.


All events and times are subject to change without notice.
-----------------------------------------------------------------
These reports are filed daily, Monday through Friday, at 12 noon,
eastern time.
-----------------------------------------------------------------
A service of the Internal Communications Branch, NASA
Headquarters.

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

Date: 28 Mar 90 19:15:48 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 03/28/90 (Forwarded)

-----------------------------------------------------------------
Wednesday, March 28, 1990                     Audio: 202/755-1788
-----------------------------------------------------------------

This is NASA Headline News For Wednesday, March 28......


The Hubble Space Telescope will be installed in the space
shuttle orbiter Discovery's payload bay tomorrow.  Small
two-winged flies, called midges, were found to have invaded the
Payload changeout room on Launch Pad 39-B on Tuesday.  There was
concern the gnat-like creatures could have fouled up the
instruments and reflective mirrors of the telescope if left in
the launch pad clean room area.   Traps were set out yesterday
and almost forty of the midges have been captured.

The Flight Readiness Review for the STS-31 mission will be held
Friday and Saturday at the Cape.  At the conclusion of the review
Saturday, the agency is expected to announce a firm launch date.



NASA astronaut William Fisher and Associate Administrator for
Space Flight William Lenoir testified yesterday before a special
hearing of the House subcommittee dealing with the NASA budget.
Fisher, co-chairman of a study group concerned with Space Station
Freedom maintenance needs, said he feels the agency can solve
several problems mentioned in a preliminary report of the study
group's findings.

Lenoir said NASA has been seriously concerned over published
stories about the preliminary findings indicating extensive EVA
requirements for station maintenance.  Fisher said advanced
robotics, new high-pressure space suits and redesign of some
station components can solve the issues.


The first mission of the air-launched Pegasus winged orbital
booster has been scheduled for April 4.  Pegasus will be launched
from beneath the wing of a NASA B-52 aircraft.  Launch will take
place over the Pacific Ocean about 60 miles southwest of
Monterey, Calif.  The payload, a 422-pound instrumented satellite
called PEGSAT, will carry a barium chemical release experiment.
The Pegasus will be put into a circular polar orbit.  NASA Select
TV will have live television coverage of the mission.








AEROSPACE DAILY reports an East German optical firm, Carl Zeiss
Jena, says it wants to sell a star tracker used on the Soviet's
Mir Space Sttion to either the European Space Agency or U.S.
space organizations.

                     ***************




-----------------------------------------------------------------
Here's the broadcast schedule for Public Affairs events on NASA
Select TV.   All times are Eastern.

Thursday, March 29......

      11:30 A.M.         NASA Update will be transmitted.


Wednesday, April 4.......

       1:00 P.M.         Coverage begins of the Pegasus launch
                         from Ames/Dryden.  B-52 takeoff at 2:00
                         P.M., with launch about 3:10 P.M.


All events and times are subject to change without notice.
-----------------------------------------------------------------
These reports are filed daily, Monday through Friday, at 12 noon,
Eastern time.
-----------------------------------------------------------------
A service of the Internal Communications Branch, NASA HQ.

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

Date: 27 Mar 90 08:42:44 GMT
From: mcsun!ukc!stc!root44!hrc63!mrcu![e-mail]  (Paul Johnson)
Subject: Re: Coilgun on a 747 - supplies to orbit at $20/lb?


Here are some rough calculations.  Say we need 3 miles per second to
get into orbit (I expect someone somewhere knows better, but stick
with that for now).  Say 15600 feet per second.

s = 1/2 a t^2

v = at

: t = v/a

: s = 1/2 . a . (v^2/a^2)

: s = (v^2)/(2a)

: a = (v^2)/(2s)

s = 231 feet.

v = 15600 f/sec.

: a = 5.3 E 5 f/sec/sec.

Say about 16000g.

You guys don't want a coil gun, you want a conventional chemical gun.

Paul.


--
Paul Johnson                               UUCP: <world>!mcvax!ukc!gec-mrc!paj
--------------------------------!-------------------------|-------------------
GEC-Marconi Research is not     | Telex: 995016 GECRES G  | Tel: [phone]
responsible for my opinions.    | Inet: [e-mail]-mrc | Fax: [phone]

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

Date: 16 Mar 90 02:06:48 GMT
From: mitel!sce!cognos!geovision![e-mail]  (Gord Deinstadt)
Subject: Re: Did SEASAT See More Than It Was Supposed To?

In article <[e-mail]> [e-mail] (Paul Tomblin) writes:
[responding to a comment that DoD has no prerogative over civilian sats]

>I seem to recall that a recent test of an SDI or ASAT weapon (sorry I forget
>deatils, just the uproar) was carried out on a perfectly good 'civilian'
>research satellite because DOD's target didn't reach orbit.  At the time,
>DOD claimed it was obsolete, but several researchers were pretty pissed off
>about it.
>
>If my memory is correct, doesn't this show that DOD does have some 'back-
>room' influence or perogative over NASA?

I think it has the same prerogative of any armed force, to shoot first and
ask questions later.  I'm sure they got their wrists slapped for it, but
as it salvaged a multi-billion dollar project at the cost of a couple
of pissed-off scientists, I'm sure they would do it again.  Most scientists
can be mollified quite nicely by a grant that wouldn't buy the Pentagon lunch.

BTW, what seasat saw that seasat wasn't supposed to see by the seashore :-)
was contours of the ocean floor.  It turns out that the ocean's surface is
deflected enough by currents flowing over shallow areas that you can chart
some pieces of the ocean's floor this way.  This made the US Navy *very*
uptight.  They consider ocean-floor charts of any accuracy to be vital
secrets; so much so that they have prevented civilian American scientists
using civilian-developed SURTASS arrays from charting the sea bed.  They're
waiting until the Russians publish.

(SURTASS = ???? - anyhow, it's a sonar system using an array of receivers
to do actual imaging rather than just *ping poop* *ping poop* sort of stuff.)
--
Gord Deinstadt  [e-mail]

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

Date: 28 Mar 90 05:39:49 GMT
From: zaphod.mps.ohio-state.edu!usc!elroy.jpl.nasa.gov!zardoz.cpd.com!dhw68k!ofa123![e-mail]  (Wales Larrison)
Subject: Intelsat Recovery (2 of 3)

Previous conclusion:  There are suitable shuttle missions for
Intelsat VI-2 retrieval.

Can the Intelsat be technically and economically retrieved?
   Intelsat VI-2 was originally designed for shuttle launch, so a pallet
design is available for manufacture to accommodate retrieval (estimate
costs at $10-30 million).  Procedures would be similar to Palapa and
Westar retrieval done in 1984.  Projected shuttle costs(long term
average costs) are in the range of $160-200 million per flight (Source:
Congressional Office of Technology Assessment Independent Shuttle Costs
Assessment).  Using the previous shuttle pricing policy guide for
allocation of shuttle costs, this yields about a $72-90 million
retrieval cost (volume limited in payload bay, weight cost basis is only
about $16-32 million).  Considering a new satellite from the Intelsat
production line is about $150 million, this appears to be a good deal
for the insurers (savings of $30-68 million), since it avoids the
production of a new, replacement satellite.
   Further operational issues need still to be resolved, primarily
verifying and validating the approach to fit within the schedule for a
specific flight.

Conclusion:  There are no major technical reasons the Intelsat VI-2
satellite cannot be retrieved.  Economically, there may be a cost
savings if the satellite is retrieved, even with recovery of shuttle
costs. This conclusion is dependent upon 1) the ability to share a
shuttle mission, 2) reuse of the satellite, and 3) the resolution of
further, more detailed technical and schedule parameters.

   Now, before I get jumped upon, a few additional comments:
   o "But the satellite isn't designed for retrieval"... Neither was
Palapa or Westar.  The astronauts hooked onto them using a "stinger"
into their boost motors, despun them using the MMU, and then hand-placed
them into their return cradles.  Intelsat VI should be able to be
handled the same way.
   o "This isn't the Shuttle's business."  Repair and retrieval of
satellites was why the shuttle was designed.  If we can do it
economically, then I think we should. (Cost discussions follow...) It
should be noted the U.S. government is one of the major members of
Intelsat, which includes representatives from 154 countries.  The U.S.
government is one of the original signers of the Intelsat accord, and is
committed by treaty.  U.S. government participation in Intelsat violates
no current public policies, laws, or regulations.
   o "Crew training costs are not included in the costs".  Actually,
according to the OTA Independent Cost Assessment, crew training costs
are covered (they included all JSC and KSC and MSFC shuttle-related
costs in their average cost price).  The OTA included all primary costs
for mission-unique crew training costs. And according to friends in the
EVA training group at JSC, they should be able to accommodate such
training as part of the standard training for an up-coming mission,
given 6 months lead time prior to the mission.  (They train for EVAs on
all shuttle missions).  They will have to build a training mockup for
use in the water tank, but this will be built (if necessary) of chicken
wire, PVC pipe, and plastic (standard materials).  I'd estimate costs at
less than $200,000 for this, which puts it well into the "noise" on my
cost estimates.
                                   (continued on next message, again!)




--
Wales Larrison
...!{dhw68k,zardoz,lawnet,conexch}!ofa123!Wales.Larrison                             [e-mail]
714 544-0934 2400/1200/300

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

Date: 29 Mar 90 00:10:15 GMT
From: zaphod.mps.ohio-state.edu!usc!cs.utexas.edu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!physics.utoronto.ca![e-mail]  (Christopher Neufeld)
Subject: Re: Discovery's Spin in 2010 (Was Re: Artificial gravity)

In article <[e-mail]> [e-mail] (Nick Watkins) writes:
>In article <[e-mail]> [e-mail] (John Roberts) writes:
>>In contrast to the clever special effects of "2001", in "2010" ...
>>I suppose it must have been pushed through by some scriptwriter who claimed
>>"It's a great special effect, and nobody will notice the inconsistency."
>Worse is the fact that "Discovery" is found tumbling end over end,
>purportedly due to the gyros seizing. The carousel could not have been
>spinning in that plane however, so the angular momentum has somehow been
>transfered through 90 degrees with no external torque. This strikes me
>as a nice trick if you can do it, but I don't think you can, am I wrong?
>
   Yes and no. You can't do what you said, but you don't have to do that
to achieve the effect seen in the movie.
   Let's assume that the angular momentum vector of the Discovery is
aligned along the long axis of the ship during its normal operation. Say
that the Discovery is pointed directly at, say, the moon. Now, let the
bearings on the carousel seize up. The ship will start to spin about its
long axis. There is a lower energy mode of this angular momentum value,
though, which is a spinning around the pitch or yaw axes. The fact that
the ship is not a perfectly rigid body, along with possible
gravitational influences from nearby Jupiter and its moons, will cause
the ship to settle into this lower energy mode, even without an external
net torque. The difference is that the ship itself will have rotated
through ninety degrees in shifting from the one mode to the other. Now,
the ship is not pointing at the moon, but is rotating around an axis
which points at the moon.
   The angular momentum of this final system is the same, while the
energy is lower.

>--
>Dr. 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]


--
 Christopher Neufeld....Just a graduate student  | "You are looking at,
 [e-mail]              | ze virld's FIRST,
 [e-mail]          Ad astra! | nuclear - magnet!"
 "Don't edit reality for the sake of simplicity" |  Siegfried of KAOS

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

End of SPACE Digest V11 #194
*******************