Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v09_5/v9_545.txt

Internet Message Format | 1991-07-08 | 16KB

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson
Received: from corsica.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr1/ota/space/[e-mail] (->+dist+/afs/andrew.cmu.edu/usr1/ota/space/space.dl) (->ota+space.digests)
          ID </afs/andrew.cmu.edu/usr1/ota/Mailbox/kYlzXk200UkVM13k47>;
          Sat, 22 Jul 89 00:32:48 -0400 (EDT)
Message-ID: <[e-mail]>
Reply-To: [e-mail]
From: [e-mail]
To: [e-mail]
Date: Sat, 22 Jul 89 00:32:33 -0400 (EDT)
Subject: SPACE Digest V9 #545

SPACE Digest                                      Volume 9 : Issue 545

Today's Topics:
       Re: Space Deaths (was Re: Killing Borgs easily)
             Re: Atari(s) and Sat Photos
              Re: Spin Angular Momentum
             Re: new space goals
    Poneer and Voyager computers (was Re: Space station computers)
             Re: Atari(s) and Sat Photos
              Re: Don't mess with NASA?
             Re: Death in Space?
Harris Corp. selected for Advanced Communications Technology work (Forwarded)
Color Screens on Space Station (Was: Procurement and future computers)
----------------------------------------------------------------------

Date: 5 Jul 89 17:32:44 GMT
From: asuvax!anasaz![e-mail]  (Scott Gibson)
Subject: Re: Space Deaths (was Re: Killing Borgs easily)

In article <[e-mail]> [e-mail] (Christopher K Davis) writes:
>US spacecraft: 7 deaths in-flight (Challenger) and 3 in a pad fire (Apollo 1).

I seem to recall that several [2? 3?] ground technicians were killed by
a leak of toxic fuel/coolant[?] from one of the shuttles.  Can someone
confirm this?   If it is true, I think these guys qualify as having given
their lives in pursuit of space travel.....

Scott

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

Date: 6 Jul 89 15:37:21 GMT
From: rex!mgse![e-mail]  (Mark Seiffert)
Subject: Re: Atari(s) and Sat Photos

In article <[e-mail]> [e-mail] (cqyang class) writes:
->Article 3587 of sci.space:
->In article <[e-mail]> [e-mail] (Frank Rahmani) writes:
->>There was a posting very recently on the net (schematics and software)
->>that used an average Atari computer to receive satpics.
->Please, folks, if you post something like this, give a more specific reference
->than "on the net".
-> Spencer at U of Toronto Zoology
-
-   I did not see that particular posting, and I hope I am not repeating what
-may have already been sent, but the September 1986 issue of 'Antic the Atari
-resource' magazine has some articles on receiving weather satellite pictures
-(WEFAX pictures) for both an Atari 800 and an Atari ST. Also 1987 and 1988
-issues of 'QST' magazine have some articles on receiving weather satellite
-pictures for different types of computers.

Could this have been the NOAA-METEOR receiver project? It was posted as
three parts on March 3rd. If so, i have it.

-
-******************************************************************************
-*                           *                                                *
-*  Jim Stinson              *     This space intentionally left blank        *
-*                           *           (sort of)                            *
-* [e-mail]   *                                                *
-*                           *                                                *
-******************************************************************************


--
Mark Seiffert,  Metairie, LA.
uucp:           rex!mgse!marks
bitnet:         [e-mail]
internet:       [e-mail]

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

Date: 6 Jul 89 11:36:11 GMT
From: pur-phy![e-mail]  (Hal Chambers)
Subject: Re: Spin Angular Momentum

In article <[e-mail]> [e-mail] (Steve Willner) writes:

>....

>An example is the spontaneous radiative decay of a hydrogen atom from
>high principle quantum number (n).  Allowed decays have change in
>orbital angular momentum (l) of +/- 1, precisely because the photon
>spin carries one unit of angular momentum.  Changes by +/- 2, 3, etc.
>are forbidden.  (Or rather, they are allowed only for multi-photon
>processes, which are generally of negligible probability . . .

Changes by (delta j = 0, +/- 2) are also permitted for one-photon
processes via magnetic-dipole or electric-quadrupole transitions.
Although of much smaller probability than electric-dipole (delta j = +/- 1)
transitions, these (generally speaking) are usually more probable
than two-photon transitions.

I don't know off-hand if magnetic-dipole (etc.) transitions are
forbidden for Hydrogen.  I was speaking to the general case.

--
Hal Chambers
[e-mail]
[e-mail]

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

Date: 6 Jul 89 02:59:11 GMT
From: amdahl!drivax![e-mail]  (MacLeod)
Subject: Re: new space goals

In article <[e-mail]> [e-mail] (Tom Neff) writes:

::Why can't we get the hardware in place for that in 10 years?

:Our track record supports my assertion better than your objection, I
:think.  We can't get that hardware ready in 10 years because we can't do
:ANYTHING in 10 years anymore.  The can-do technocracy that gave us
:Vietnam and Apollo is ancient history.  It's suicidally futile to
:predicate a Mars mission on JFK rising Arthur-like from the grave.  We
:have to design something around the do-able.

I think the fire is out.  Thirty years from now Japanese children will
laugh their heads off at sitcoms based on the problems of Japanese farmowners
in the Louisiana rice fields with their mumbling, child-like, illiterate
American fieldhands.  Americans won't have to worry about being perceived
as noisy tourists anymore - that image will be replaced by that of a
marginally retarded illiterate manual laborer.

Michael Sloan Macleod  (amdahl!drivax!macleod)

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

Date: 6 Jul 89 17:55:31 GMT
From: blake!ndsuvax![e-mail]  (Glen Overby)
Subject: Poneer and Voyager computers (was Re: Space station computers)

There's been a lot of talk about the shuttle and space station computers,
and with Voyager 2's upcoming Neptune encounter, I've been wondering
what kind of computers are used on the Voyagers (and predecessors, such as
Pioneer 10 and 11).

Their manufacturer can truly say that their computers are out of this solar
system :-)

Send replies directly to me and I'll summarise in a week or so.
--
        Glen Overby    <[e-mail]>
    uunet!ndsuvax!ncoverby (UUCP)    ncoverby@ndsuvax (Bitnet)

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

Date: 6 Jul 89 23:05:54 GMT
From: att!ihlpl![e-mail]  (Knudsen)
Subject: Re: Atari(s) and Sat Photos

In article <[e-mail]>, [e-mail] (cqyang class) writes:
> may have already been sent, but the September 1986 issue of 'Antic the Atari
> resource' magazine has some articles on receiving weather satellite pictures
> (WEFAX pictures) for both an Atari 800 and an Atari ST. Also 1987 and 1988
> issues of 'QST' magazine have some articles on receiving weather satellite
> pictures for different types of computers.

A few years back The Rainbow magazine had quite an article and
program for receiving WEFEX pix on the RadShack Color Computer.
Just plug the receiver's speaker output into the cassette port,
and software does the rest.

BTW, we are talking about shortwave rebradcasts of WEFAX.
Or do the direct satellite signals use the same audio-fax modulation?

--
Mike Knudsen  Bell Labs(AT&T)   att!ihlpl!knudsen  [e-mail]
  Round and round the while() loop goes;
  "Whether it stops," Turing says, "no one knows!"
Shotguns -- just say PULL!

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

Date: 6 Jul 89 10:48:30 GMT
From: mcvax!ukc!stl!stc![e-mail]  (Peter Kendell)
Subject: Re: Don't mess with NASA?

From article <[e-mail]>, by [e-mail]:

} You missed a little of the joke.  I was "chiding" Henry for wanting to
} ride in a "real" airplane with afterburners when he is such a strong
} proponent of free enterprise and the stamping out of government
} funding and interference.  Concorde was a government project the whole
} way so it would fail that particular test, as do virtually all
} fighters (except the F-20).

    Point taken. However, don't forget that Concorde was a joint
    British and French government enterprise with the objective of
    producing a plane that could be sold on the open market to
    civilian airlines.  I know that's not what actually happened -
    better informed persons than myself may well know more than I
    do about the reasons for this.  I think there's a difference
    between this and the Air Force going to a contractor and saying
    build this plane to these specs under our supervision for us to
    use (and maybe sell to friendly powers).

} Concorde is an exceptionally nice airplane to fly in and Air France
} feeds you marvelously for the entire trip.  I was eating truffled
} lobster and sipping champagne when we went through Mach 2.  That
} really felt decadent!

    I bet! I used to live about 20 miles west of Heathrow airport
    and Concorde was *by far* the noisiest plane to fly over. You
    have to imagine a truck with a shot exhaust system about 20
    feet over your head to get an idea of the racket - a sort of
    growling booming crackling noise. I don't suppose the
    afterburners were running at this point; heaven only knows
    what it would have been like if they had.
--
----------------------------------------------------------------------------
|          Peter Kendell <[e-mail]>                   |
|                ...{uunet!}mcvax!ukc!stc!pete           |
----------------------------------------------------------------------------

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

Date: 6 Jul 89 18:09:36 GMT
From: [e-mail]  (Eugene Miya)
Subject: Re: Death in Space?

In article <[e-mail]> [e-mail] (Christopher K Davis) writes:
>- In article <[e-mail]>, rjd@brunix (Rob Demillo) writes:
>- > Seven people were lost in our effort to get off this planet...
> Numerous other guesses on casualities.
>So at least 16.

Silly people! 8)
You can't try answer an ill-posed non-question.  It seems you are
implying a person has to die in a spacecraft, or one the way, etc.
You discount (make worthless) all the flight test pilots, technicians, etc.
If you count these we are talking hundreds (since WW-II).  We lost
a plane with 9 people which collided with an Orion.  Several techs
died in a LN2 accidents.  You also neglect the "walking wounded."
No bounds on either time or location were given.  Nearly 100 test
pilots have died at Edwards alone.  Vultures counting nits.

Another gross generalization from

--eugene miya, NASA Ames Research Center, [e-mail]
  resident cynic at the Rock of Ages Home for Retired Hackers:
  "You trust the `reply' command with all those different mailers out there?"
  "If my mail does not reach you, please accept my apology."
  {ncar,decwrl,hplabs,uunet}!ames!eugene
                  Live free or die.

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

Date: 6 Jul 89 19:55:21 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Harris Corp. selected for Advanced Communications Technology work (Forwarded)

Paula Cleggett-Haleim
Headquarters, Washington, D.C.                       July 6, 1989

Mary Ann Peto
Lewis Research Center, Cleveland

RELEASE:  89-109

HARRIS CORP. SELECTED FOR ADVANCED COMMUNICATIONS TECHNOLOGY WORK

     NASA Lewis Research Center, Cleveland, today announced the
selection of the Harris Corp., Melbourne, Fla., for final
negotiations leading to award of a contract to develop a
prototype Earth station for use with the Advanced Communications
Technology Satellite (ACTS).

     ACTS is a key element in NASA's efforts to develop high-
risk, advanced communications technology usable in the higher
frequency bands to support our nation's future communications
needs.  Realization of this goal will enable the U.S. to maintain
preeminence in satellite communications.

     The prototype unit will be developed on the basis of cost-
plus-incentive-fee.  The contract will become effective in late
summer and last approximately 24 months.  The contractor-proposed
price is $3.4 million for the prototype development.

     The proposed Earth station will have the capability for
multichannel voice and data services at data rates up to l.544
megabits per second.  The prototype unit will be designed so that
additional units can be built at low cost for the ACTS experiment
program.  The anticipated contract will include options for the
procurement of additional low-cost units, depending upon the
future needs of the ACTS experiment program.

     ACTS is under development for launch from the Shuttle in May
l992 for a planned 2-year experiments mission.  The ACTS system
will be made available to the public and private sectors
(corporations, universities and government agencies) for
experimentation.  Experimenters will test, evaluate and determine
the feasibility of key ACTS system technologies.

     Work on the prototype Earth station will be performed at the
contractor's plant in Palm Bay, Fla.

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

Date: 6 Jul 89 23:43:46 GMT
From: rennet.cs.wisc.edu![e-mail]  (Stuart Friedberg)
Subject: Color Screens on Space Station (Was: Procurement and future computers)

[e-mail] (Henry Spencer) writes:
>Those designers obviously have never talked to remote-sensing people,
>who do *not* consider 8 bits per color really adequate.  Said folks would
>really prefer 10 or 12 (although of course they have to take what they
>can get...).  And this is a lot more relevant to the space station than
>arguments about how many thousands of dots per inch you need to reproduce
>fine art well enough to satisfy museum experts...

Unfortunately, this is all sheer fantasy!  Read the (Soviet) article in
the most recent Scientific American and notice the as-yet-unexplained
variations in human color sensitivity observed in Mir experiments.
The human eye aboard a space station changes in both sensitivity and
spectral resolution in ways that are both frequency-, and time-,
dependent.

To actually make use of those 10 or 12 bits per color, you'd have to run
a "gamma" correction that varied not only according to the monitor, but
also the user, and the user's biological rythms (these changes are
periodic).  Ivan shows Stefan an image and the colors go weird.  1/2 :-)

And, this is all fantasy for another reason.  Sophisticated image
analysis will continue to be done on the ground for the forseeable
future for the most rational of all reasons:  professional analysts
and their equipment are too bulky and too heavy to put into space
economically.  Rough cut adjustments that could be made on board
certainly do not require precision displays.

I have a hard time imagining ANY realistic space station tasks that
need AS MUCH spatial or color resolution as a current Mac, Amiga, or
Atari.  Larger displays, certainly.  A variety of input devices,
certainly.  But 72 dpi, 4 (too few) to 8 (too many!) fixed colors,
should be ample for robust command/control interfaces.  For
command/control, each color should mean something and subtle shades
only obscure important differences.  A significant minority of males
have a hard time even telling red from green!

Similar spatial resolution and 8 bits is ample for experimental
displays requiring grey scale.  Docking has been done using video of
much worse spatial and intensity resolutions.  Where more information
must be displayed, very good false color displays can be produced with
a 12 bit frame buffer and and a loadable 12 -> 8,8,8 color map.  (On a
decaying '70's vintage piece of hardware, no less.)

You may disagree about exactly what is required, but please keep these
two design principles in mind:

1) If the bits don't carry useful information, they are either
   decoration or a distraction.

2) Minimizing the distinctions a human has to make increases
   safety and reliability.

Stu Friedberg  ([e-mail])

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

End of SPACE Digest V9 #545
*******************