Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_2/V11_204.TXT

Internet Message Format | 1991-07-08 | 17KB

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson
Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/[e-mail] (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests)
          ID </afs/andrew.cmu.edu/usr1/ota/Mailbox/wa55IbW00VcJ81y043>;
          Sat, 31 Mar 90 01:58:48 -0500 (EST)
Message-ID: <Ma55I=[e-mail]>
Reply-To: [e-mail]
From: [e-mail]
To: [e-mail]
Date: Sat, 31 Mar 90 01:58:20 -0500 (EST)
Subject: SPACE Digest V11 #204

SPACE Digest                                     Volume 11 : Issue 204

Today's Topics:
              Re: Martian Standard Time
               Re: Solar Cells
          Re: Will we lose another orbiter?
        IQ scores (was: Will we lose another orbiter?)
       Re: NASA Headline News for 03/29/90 (Forwarded)
             Net around the tank
             Re: Discovery's Spin in 2010
        Re: Viewing the Space Shuttle landing
               Shuttle landings
                   Needles
            Satellite information
            SPACE Digest V11 #195
----------------------------------------------------------------------

Date:     Fri, 30 Mar 1990 16:09 EST
From: SIMMONS DONALD F  <[e-mail]>
Subject:  Re: Martian Standard Time
To: <[e-mail]>


aramis.rutgers.edu!athos.rutgers.edu![e-mail] (Steve Masticola)
writes:

>Just out of curiosity, how large and bright would Deimos and Phobos
>appear from the Martian surface? Would they have features observable
>to the naked eye? Cast shadows?

>I don't think they're massive enough to cause large tides, but they
>might be worth incorporating into a calendar for other reasons. Or
>not.

Kind of hard to have tides when you don't have oceans :-)

Donald Simmons    27000@AECLCR
"Lie to you? I don't even know you!"

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

Date: 30 Mar 90 20:56:41 GMT
From: eagle![e-mail]  (Dave McKissock)
Subject: Re: Solar Cells

In article <[e-mail]>,
[e-mail] writes:
> 3. What is the solar energy 'flux' at Earth orbit.
> 4. What kind of effeciencies do people use when doing solar power
>    satellite studies.

In a Space Station document that defines the environment, the solar
constant is defined as 1371 plus or minus 5 W/square-meter at one
AU. Due to the eccentricity of the earth's orbit, the yearly minimum
solar flux is 1321 W/sq-m, & the yearly maximum is 1423 W/sq-m.

The Freedom solar cells have an efficiency of about 14%.
--
-----------------------------------------------------------------------
Dave McKissock              [e-mail]

Note: If you wish to respond to me directly, DON'T SEND THE MSG TO
the REPLY TO address, as it won't work. Instead use the above address.

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
NASA LeRC: Responsible for the remarkable & ingenious Space Station
           Freedom Electrical Power System
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Opinions expressed herein probably bear absolutely no resemblance to
the official NASA position.
-----------------------------------------------------------------------

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

Date: 30 Mar 90 19:45:33 GMT
From: rochester![e-mail]  (Paul Dietz)
Subject: Re: Will we lose another orbiter?

In article <[e-mail]> [e-mail] (Lou Adornato) writes:
>
>Throughout my lifetime, we Americans have had a growing tendency to leave the
>"details" of the technology on which we depend to "experts", and then turn
>on the "eggheads" when anything goes wrong.  A case in point is the present
>attitude about the original launch rate.  It seems that the clarity of our
>hindsight is now considered proof that NASA was actively lying.

Actually, the original launch rate (60) was demonstrably absurd.
There wouldn't have been a budget big enough to buy that many
payloads.  But NASA supplied bogus numbers anyway.  And any rational
observer just before Challenger would have seen that NASA couldn't hit
24 flights/year -- they were stretched to the breaking point as it was.
Read the Rogers report.

>The launch rate had little to do with the Challenger disaster.  A slip of a
>few days wouldn't have had that big an impact on the annual launch rate that
>NASA was pushing at that time.  The direct cause of the accident was a mindset
>by a handful of Huntsville managers that put the Thiokol engineers in the
>position of having to _prove_ that it was unsafe to launch.

This is false.  The alternative was waiting until April ("My god,
Thiokol,..."), when the weather would be warm enough to not be out of
the range of previous experience.  If they had held, they would have
had to have held for months, not days.  More broadly, NASA had been
ignoring the booster problem (and other problems) for a long time,
in the face of repeated warnings.

>I'm not going
>to be cast as apologist for these idiots.  As far as I'm concerned, they
>should have been liable to criminal prosecution.  But the real source of the
>"must do" mindset was a desperate desire to stay off the critical path,
>fueled by the public belief (which goes all the way back to the 60's) that
>launch delays are caused either by bumbling or fraud.

Your remarks *do* cast you as an apologist, no matter how you deny it.
The responsibility for a safe launch rested on NASA, and nowhere else.

>>It was NASA's responsibility to inform the public about the safe
>>flight rate of the system, not recklessly exceed it in a futile
>>attempt to preserve the myth of the shuttle's economic viability.  It
>>was NASA's responsibility to be honest about the potential
>>capabilities of the shuttle when it was being sold.
>
>We _are_ talking about the same public that thought that Gallileo was going
>to make Florida uninhabitanble for the next 10,000 years, right?

No -- that's a lunatic fringe.  I ask you: if they were the same "public",
why didn't NASA, which you think is a cowering agency controlled by public
opinion, go along and not launch Galileo?

>Dealing with overblown expectations isn't as easy as you make it sound.  NASA
>is currently in the process of trying to downscale the public expectations
>of the space station.

Yes, let's give a big hearty cheer that NASA, eight years into the
space station program, finally decides to add up the EVA requirements.
They must have misplaced their calculators before.

And let's give a nice big Gold Plated NASA Managment Hat Award to
Lenoir for his cavalier dismissal of the report when it leaked out.

>Look at all of the NASA-bashing that's been going on
>in this newsgroup over that.  I think it's pretty clear that NASA is in a
>no win situation, and has been since long before the accident.

Perhaps their no-win situation is a product of their own duplicity?

>Just as an aside, how much funding do you think NASA would have gotten for
>a safety redesign of the already unpopular shuttle if it had grounded the
>entire fleet in '86 _before_ the accident?

I see, Lou; lying is ok if it preserves your program and budget.  I
think they would have gotten some, but the space station would have
been in danger.  So they didn't ask.

It's NASA's responsibility to be honest with the public, even if that
means giving the public bad news that may harm NASA.

>>                                                     But, as Keyworth
>>noted, NASA is the only government agency that outright lies.
>
>What makes you think the same thing wouldn't have happened to a private
>contractor?

Eh?  You logic here is undecipherable.  Where did I mention private
contractors?

    Paul F. Dietz
    [e-mail]

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

Date: 30 Mar 90 19:55:25 GMT
From: zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!dsinc!netnews.upenn.edu!linc.cis.upenn.edu![e-mail]  (Robert Rubinoff)
Subject: IQ scores (was: Will we lose another orbiter?)

In article <[e-mail]> [e-mail] (Lou Adornato) writes:
> [...]  One of the perks of the engineering biz is
>that you get to deal mostly with intelligent, educated people.  The drawback
>is that you forget that the average IQ is, by definition, 50.


Umm...actualy, the average IQ is, by definition, 100.  Of course, what that
means is that some particular IQ test was calibrated in some manner, and the
average score in the calibration was called 100.  There's no guarantee that
other tests would have the same score distribution, or indeed that the general
popluation (then or now) would have the same distribution.  Although I imagine
that psychologists make some attempt to keep the tests properly calibrated.

On the other hand, it's not clear what "IQ" really means, anyway, except in a
very general sense.

   Robert

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

Date: 30 Mar 90 04:46:44 GMT
From: munnari.oz.au!murtoa.cs.mu.oz.au!ditmela!yarra!melba.bby.oz.au![e-mail]  (Gregory N. Bond)
Subject: Re: NASA Headline News for 03/29/90 (Forwarded)

In article <[e-mail]> [e-mail] (Peter E. Yee) writes:

   On Capitol Hill yesterday, Dr. William Lenoir, Associate
   Administrator for Space Flight, told a Senate subcommittee
   dealing with space that NASA will rely heavily on automation and
   robotics to reduce maintenance space walks by astronauts for
   Space Station Freedom.  Lenoir was responding to published
   reports that were extremely critical of the space station
   maintenance requirements and the need for extensive
   extravehicular activity to service the station in orbit.

Robots?  What robots?

Its takes a million years and a zillion dollars to make a manipulator
arm, human controlled. They still don't have a viable EVA
suit/propulsion unit.   Where are they going to get robots capable of
changing AE-31 units from?  Ask HAL to design them??
--
Gregory Bond, Burdett Buckeridge & Young Ltd, Melbourne, Australia
Internet: [e-mail]    non-MX: [e-mail]
Uucp: {uunet,pyramid,ubc-cs,ukc,mcvax,prlb2,nttlab...}!munnari!melba.bby.oz!gnb

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

Date: 30 Mar 90 13:04:14 GMT
From: mcsun!hp4nl!ruuinf!praxis![e-mail]  (Almanak Commissie)
Subject: Net around the tank

While I was wading through my piles of articles, newspapers and photographs
about the Shuttle I re-discovered an old (1980) photograph. It pictured
Columbia on the pad with a giant net attached around the External Tank.
 It was fastened around the tank at about the height of the access-arm to
the Shuttle cabin, but it didn't look like a safety-net (in case someone
would drop out of the White Room) becaus it was winded very tightly around
the ET. Does anybody know why the net was there? Was it to hold the insulation
to the tank or something?

---- Gert-Jan Bartelds

--------------------------------------------------------------------------
Gert-Jan Bartelds      |  [e-mail]
Dept. of Astronomy     | My favourite discussion goes like this:
University of Utrecht  | Are you studying Astrology? No, it's Astronomy!
Holland                | But I thought that... No, it's Astronomy
---------------------------------------------------------------------------
  Rene : I will mail this only once

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

X-Delivery-Notice:  SMTP MAIL FROM does not correspond to sender.
Date: Fri, 30 Mar 90  14:41:17 EST
From: [e-mail]
      (Chip [e-mail])
Subject: Re: Discovery's Spin in 2010

[e-mail]  (Kieran A. Carroll) writes:

 >>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?

 >An aspect of the rotational dynamics of satellites that's well-known
 >to spacecraft dynamicists (and has been since after Discoverer I went
 >tumbling) is that rotation of a long, thin body (like the Discovery)
 >about it's long axis is unstable (Newtonian mechanics predicts
 >it to be neutrally stable; however, internal energy dissipation --
 >damping -- causes it to be unstable), while rotation about either
 >of the two short axes (``tumbling'') is stable. Thus, while Discovery
 >would have >initially< started spinning about its long axis when
 >the carousel ceased spinning relative to the main spacecraft (gyros
 >seizing? Perhaps you meant bearings?), this spin would would fairly
 >quickly have evolved into the end-over-end tumble used in the story.

It's been a while since I saw the movie, but I'm pretty sure the carousel's
axis of rotation was "vertical", perpendicular to the long axis of the
spacecraft.  Access through the carousel was through the axis, and the
bridge was "above" it and the pod bay "below" it- this is evident looking
at the bow of the spacecraft from outside.  Therefore, as the rotation slowed
down, the spacecraft would have begun to rotate about one of its short axes-
but in a flat spin, not end-over-end as depicted in the movie, right?  I'm
not a physicist,  so there may be something gyroscopic I'm missing here.

                                   -Chip Olson, UMass-Amherst.

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

Date: 21 Mar 90 13:14:19 GMT
From: att!cbnews![e-mail]  (erik.j.kramer)
Subject: Re: Viewing the Space Shuttle landing


How about a posting which describes "Viewing Space Shuttle Lauchings"
for the benefit of those of us on the East Coast?  Anyone from Kennedy
able to share that info with us?

        Erik Kramer
        att!mvups!ejk

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

Date:     Fri, 30 Mar 1990 09:28 EST
From: SIMMONS DONALD F  <[e-mail]>
Subject:  Shuttle landings
To: <[e-mail]>

Why exactly did the shuttle make only a few landings at its special runway
outside the Kennedy Space Center, and then they switched back to Edwards?
I remember hearing somewhere that its brakes had something to do with it.
Anyone know the whole story?

Donald Simmons    27000@AECLCR
"Lie to you? I don't even know you! - Reuben Flagg"

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

Date: 30 Mar 90 14:52:09 GMT
From: cs.utexas.edu!news-server.csri.toronto.edu!utgpu!watserv1!watdragon!watyew![e-mail]  (Brian or James)
Subject: Needles


 Does anyone out there have information on an early (late fities
to mid-sixties) project to place millions of needled in LEO as a
passive radio relay. I *think* it was DOD related (a stop gap
technique to use if the US comsats got fried) and I recall Clarke
discussing it briefly in on of his books. The needles, if they were
launched, obviously must have reentered long ago, if only because
noone ever  has a payload turned into a sieve by hordes of orbitting
sewing tools. The radio astronomers must have *loved* this project.
The recent talk of 'smart rocks'. 'brilliant pebbles' and 'savant sand'
put me in mind of it.
                        James Nicoll
PS: Smilies where necessary.

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

Date: 30 Mar 90 20:59:58 GMT
From: ccncsu!longs.LANCE.ColoState.Edu![e-mail]  (Lee Jarvie)
Subject: Satellite information


If anyone out there knows where I can find data that has been collected
by various satellites, it would be greatly appreciated.  I have no
specific data in mind, I just would like a general idea on where to find
it.  I never realized this data was available before, but I guess (other
than military) there's no reason why it wouldn't be.  If anyone knows,
please either send me e-mail or post it.

Thanks in advance.
Lee

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

[e-mail]                 Lee Jarvie

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

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

Date:        Fri, 30 Mar 90 15:53:52 CST
From: Andy Edeburn <[e-mail]>
To: <[e-mail]>
Subject: SPACE Digest V11 #195


 I was wondering if someone had a complete listing of all the shuttle
launches currently scheduled and their respective payloads. Thanks!

+-----------------------------------------------+
| Andy Edeburn - "I see nothing!" -Sgt. Schultz |
+-----------------------------------------------+
| InterNET: CC62%SDSUMUS.BITNET @ SD.STATE.EDU  |
+-----------------------------------------------+

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

End of SPACE Digest V11 #204
*******************