Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_1/V11_171.TXT

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Subject: SPACE Digest V11 #171

SPACE Digest                                     Volume 11 : Issue 171

Today's Topics:
              More space station news...
          Viewing the Space Shuttle landing
               Re: Geostationary orbit
         Re: Commercial Titan/Intelsat Launch Failure
             Re: Shuttle Escapes
        Re: What was Challenger really up to?
     Re: Coilgun on a 747 - supplies to orbit at $20/lb?
----------------------------------------------------------------------

Date: 20 Mar 90 14:58:18 GMT
From: zaphod.mps.ohio-state.edu!wuarchive!kuhub.cc.ukans.edu![e-mail]
Subject: More space station news...

Thought my fellow netters would be interested in this report on the
Incredible Shrinking Violet Space Station, ExpensiveDom... These
stories came off the AP wire today (3/19/90):

*****

Report: NASA Investigators Conclude Space Station Plans Flawed

NEW YORK (AP) Q The planned space station Freedom cannot be built as
designed because its thousands of parts would begin breaking down even
before the station was fully assembled in space, according to a
published report.

The New York Times said in today's editions that the National
Aeronautics and Space Administration still was not sure exactly how to
remedy the design flaws in the $30 billion space station. The project
is to be the centerpiece of plans to have astronauts explore the solar
system.

The problem was discovered by a team of NASA investigators early
this year who calculated the likelihood of the station's thousands of
parts failing in a given time period.They found that even before
construction is three-quarters complete, it would be time for major
maintenance and overhaul of the space station. Construction is expected
to take five years.

NASA's plans call for the station to serve as an orbiting outpost from
which astronauts would conduct a variety of scientific studies and
explore the solar system. So far, almost $4 billion has been spent on
design studies and other preliminary work.If built according to plan,
the space station would have more than 5,500 external parts that would
need to be replaced if they failed, investigators concluded.

Officials calculated the likelihood of failure, the time required to
replace the parts, and determined that the station would need about
2,200 hours of maintenance each year by astronauts working in space
suits.

Space walks entail risks that range from radiation exposure to flying
space debris.

*****

NASA Says It's Working to Resolve Space Station Maintenance Problem

By HARRY F. ROSENTHAL
Associated Press Writer

WASHINGTON (AP) Q NASA said today that its engineers have worried for
years that astronauts will have to spend too much time in the harsh
environment of open space to repair and maintain the space station that
is set for construction in the mid-90s.

Agency officials were preparing a response to a front-page article in
the New York Times today that said the station can't be built as
designed "because its vast array of parts would start to break down
before the station was completed."

The first elements of the $30 billion station are to be carried into
orbit beginning early in 1995 and completion is scheduled for 1999.
The Times said NASA investigators found that construction would be
only 60 percent to 70 percent complete before preventive maintenance
would have to begin.

The Times said investigators concluded that, if built according to
plan, the space station would have more than 5,500 external parts
that would need to be replaced if they failed. That would require
space walks, or what NASA calls EVAs, short for extra-vehicular
activity.

"In terms of the program addressing EVAs, that is not a new thing;
it's not a new problem that has suddenly been discovered," said space
station spokesman Mark Hess.The Times said such space walks would total
2,200 hours for maintenance, but Hess said that estimate includes a
lot of time in which astronauts would not actually be outside of the
relative safety of the station.

Another spokesman, James McCulla, said EVA time "is a matter that
space station designers have been working on for years."

He said that working out methods to cut down the EVA time is an
integral part of design review activities "and therefore will
be an important matter to be worked on for days to come."

*****

Interesting, no? Makes you long for the days when things could be
done simply and easily at the space agency...

Travis Butler                     Argue ideas,
[e-mail]         not sources

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

Date: 20 Mar 90 21:12:31 GMT
From: skipper![e-mail]  (Mary Shafer (OFV))
Subject: Viewing the Space Shuttle landing


[Sorry--I'm a little late with this.  At least they haven't launched
yet.  MFS]

There are four ways to see the Shuttle landing at Edwards AFB, listed
in order of restrictiveness of access.

     1.  The public viewing area on the lakebed.  Take Hwy 14 to Avenue
         F and follow the signs.  This area is opened about 2 days
         before the scheduled touchdown.  The viewing area is an
         unimproved area so don't expect many amenities.  I think that
         there are sanitary facilities and that food and drinks can be
         purchased.  It's suggested that you bring food and water
         Nothing is required for access to this area.  (I've never been
         to this area, so I can't speak from personal knowledge.)

     2.  The hillside viewing area.  This is on the hillside, just
         above Ames-Dryden, and requires a special pass.  This pass is
         good for one vehicle, with any number of passengers.  You
         can't enter the Ames-Dryden complex but you can walk down the
         hill to the cafeteria and the giftshop, etc.  More amenities,
         including radio transmissions from the Shuttle and JSC.  Some
         of us believe that this area has the BEST view of the landing.

         These passes can be obtained by writing, as detailed below.
         Ames-Dryden employees can also obtain them.

     3.  Official guest.  Access to the Ames-Dryden complex.  You get
         to watch the landing from the ramp, which is right on the
         lakebed.  (The Shuttle lands some distance away, depending on
         which runway it uses.) The crew speaks to the crowd just
         before they return to JSC.  There are special aircraft
         displays (including the SR-71, F-15, F-18, X-29, etc.) in the
         hangars.  The radio transmissions are broadcast.

         You can write, as detailed below, to obtain these badges and
         parking permits.  Employees are allotted one car pass and four
         badges for family and friends.

     4.  Distinguished guest.  As 3 above, with the viewing being done
         from the complex roof.  This group includes the families and
         guests of the astronauts and notables (of a variety of
         types--Dick Rutan was at a recent landing) in the aerospace
         community, etc.  These people are invited by NASA management
         and the list is fairly small.

To obtain a hillside pass or official guest badges, write to:

     NASA Ames-Dryden Flight Research Facility
     Attn:  Public Affairs Office
     P.O. Box 273
     Edwards, CA  92523-5000

Do this early, because there is a limited amount of space.  If you get
these and then discover that you can't attend, please try to pass them
on to someone else who can use them.  Incidently, there is _no_ charge
for any of these.

Come see the Shuttle land--it's great.

--

Mary Shafer  [e-mail] or ames!skipper.dfrf.nasa.gov!shafer
         NASA Ames Dryden Flight Research Facility, Edwards, CA
                   Of course I don't speak for NASA

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

Date: 20 Mar 90 23:22:27 GMT
From: zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!physics.utoronto.ca![e-mail]  (Christopher Neufeld)
Subject: Re: Geostationary orbit

In article <[e-mail]> [e-mail] writes:
>[e-mail] (Christopher Schaller) writes:
>
>>Quick question!
>>How high does a satellite have to be to atain  geostationary orbit
>
>A satellite on the ground has a very nice geostationary orbit.
>
>>geosynchrous orbit?
>
>About 22,000 miles.
>
>>                   Chris.
>
>-Johnny

   For both geostationary and geosynchronous orbits, other than the
trivial example given by Johnny, the height is about 36000 km.
   A geostationary orbit is an orbit over the equator, moving in the
same direction as the Earth rotates, at 36000 km. An observer on the
ground can look up and always see the orbiting body in the same position
in the sky.
   A geosynchronous orbit is any orbit at 36000 km which does not move
in the opposite direction to the Earth's rotation. For instance, if I
moved straight up 36000 km, and then acquired the correct velocity due
East, I would be in a geosynchronous orbit going between about 47
degrees North and South latitudes. Seen from the ground, I would appear
to move in a figure-eight pattern, but one which is always in the same
position in the sky.
   So, geostationary orbit is a 24 hour (or is it 23h56m4.09s?) orbit
which follows the equator, while a geosynchronous orbit is a 24 hour
orbit which does not necessarily follow the equator.


--
 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

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

Date: 19 Mar 90 16:15:48 GMT
From: idacrd![e-mail]  (Robert McGwier)
Subject: Re: Commercial Titan/Intelsat Launch Failure

From article <[e-mail]>, by [e-mail] (George William Herbert):
> Yesterdays attempted launch of a commercial Titan III with an Intelsat VI
> comsat aboard apparently failed.  From sketchy reports, it looks like the
> transfer stage did not seperate from the second stage, and the Intelsat VI
>


My ``Martin Marietta sources" have told me that the seperation computer
control code was flawed.  The hardware all tested fine on the ground when
test software was run.  The flight code that was accidentally loaded
was designed for a TWO SATELLITE mission.  The satellite that was on board
was in the second satellite position if there had been two birds on board.
The software was looking for a  wire to be severed that would have
signalled that the first satellite had been successfully ejected.  Since
there was none, the hardware lockouts could not then successfully be
overridden and the software could not be changed from the ground for
whatever reason.  Probably no receivers and/or no time before the batteries
in the final stage give out.

Bob

--
____________________________________________________________________________
    My opinions are my own no matter    |    Robert W. McGwier, N4HY
    who I work for! ;-)            |    CCR, AMSAT, etc.
----------------------------------------------------------------------------

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

Date: 19 Mar 90 21:33:43 GMT
From: cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Shuttle Escapes

In article <19.Mar.90.13:22:[e-mail]> [e-mail] writes:
>Just how difficult is it to get a reasonably well protected human from
>low earth orbit to the ground alive and without a space craft?  Is it possible
>to lose velocity slow enough that heat shields are not required?

In theory it can be done.  With a specially-designed deceleration parachute,
the deceleration can be done at extreme altitude and the heat loads are
within the range that current spacesuits can handle.  One would then need
a more normal parachute for the final landing.  (Actually, I expect one
would need a fairly hefty parachute, since suit plus backpack plus etc.
add quite a bit of weight.)  Nobody has actually flown hardware to test
this, mind you, let alone tried it in person.
--
MSDOS, abbrev:  Maybe SomeDay |     Henry Spencer at U of Toronto Zoology
an Operating System.          | uunet!attcan!utzoo!henry [e-mail]

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

Date: 20 Mar 90 00:55:59 GMT
From: [e-mail]  (Richard Johnson)
Subject: Re: What was Challenger really up to?

[e-mail] (Arnold G. Gill) writes:
>
>      I heard the following story from a friend...
>
>      The real cause of the Challenger accident was not O-ring failure as we
> are all meant to believe, but rather due to an accidental discharge of the
> military laser being carried (illegally) up into orbit, which blasted through
> the shuttle and exploded the fuel tanks.

That story sounds a lot like the fantasies my friends and I used to come
up with when we were 10 years old.  You requested serios refutations, but
it's difficult to make any such statements about something so sophomoric.
All I can do is point out that the so-called evidence is incomplete.  It
took a long while to find the crew cabin because its hard to find things
under even shallow water (otherwise we'd have discovered all shipwrecks of
interest by now).  I'd also like to know *which* crew member was the
supposed laser expert.  Simply stating there was "[a] laser expert on
board" will only convince those 10 year olds who want to believe something
fishy was going on.  The bit about erased portions of the cockpit recorder
tape is also incomplete.  What was supposedly erased, and from *where* in
the transcript?

I don't thing the much-maligned Christic Institute would even bother with
this one.

| Richard Johnson                           [e-mail] |
|    CSC doesn't necessarily share my opinions, but is welcome to.     |
|  Power Tower.>.Dual Keel.>.Phase One.>.Allison/bertha/Colleen.>.?... |
|   Space Station Freedom is Dead.  Long Live Space Station Freedom!   |

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

Date: 20 Mar 90 04:42:45 GMT
From: ogicse!caesar.cs.montana.edu!samsung!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!srcsip!jhereg!wd0gol!newave![e-mail]  (John A. Weeks III)
Subject: Re: Coilgun on a 747 - supplies to orbit at $20/lb?

In article <[e-mail]> [e-mail] (Walt Leipold) writes:
> If you're really launching significant masses (> 20 kg/min?), you could
> probably keep the 747 in the air using "mass driver" propulsion. (Now,
> all we've gotta do is find a power source for that sucker...)

Cold fusion, of course.  Something about the size of a wine bottle should
do it.  Take two just in case... 8-)

-john-

--
===============================================================================
John A. Weeks III               [phone]               [e-mail]
NeWave Communications                ...uunet!rosevax!bungia!wd0gol!newave!john
===============================================================================

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

End of SPACE Digest V11 #171
*******************