Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V10_1/V10_191.TXT

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Subject: SPACE Digest V10 #191

SPACE Digest                                     Volume 10 : Issue 191

Today's Topics:
             To the Voyager Team
               What do you do?
        Re: Computer Virus (Future Processors)
            KSC Payload Update (Forwarded)
         Re: KH-11 or Lacrosse power sources?
           Re: What would we do WITHOUT 'Freedom'?
         Re: Asteroids as weapons of mass destruction
               Re: Asteroid Collisions
         NASA Headline News for 10/27/89 (Forwarded)
            Re: Galileo Questions
     Re: Trying to build a fluxgate magnetometer -- help!
----------------------------------------------------------------------

Date: 26 Oct 89 22:39:04 GMT
From: gem.mps.ohio-state.edu!usc!henry.jpl.nasa.gov!elroy.jpl.nasa.gov!forsight!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: To the Voyager Team


Quote by Richard Truly, Administrator, NASA, from the Voyager Bulletin,
10/4/89.

   "You have earned the highest marks for making the solar system
    intelligible to the world at large in a most meaningful way.
    The intregity of the program and its participants was manifest
    to the world; we are all extremely proud of it.
    I salute the entire Voyager team from the first and last for such
    a significant and permament positive addition to human knowledge
    and human horizon. This was the kind of excitement that counts.
    Well done!"


 Ron Baalke                       |    [phone] x260
 Jet Propulsion Lab  M/S 301-355  |    [e-mail]
 4800 Oak Grove Dr.               |
 Pasadena, CA 91109               |

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

Date: 27 Oct 89 20:13:27 GMT
From: henry.jpl.nasa.gov!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: What do you do?


Please share with us the type of work you netlanders do that is related
to space. Please post it here.


 Ron Baalke                       |    [phone] x260
 Jet Propulsion Lab  M/S 301-355  |    [e-mail]
 4800 Oak Grove Dr.               |
 Pasadena, CA 91109               |

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

Date: 27 Oct 89 16:11:06 GMT
From: pikes![e-mail]  (Scott Casto Pinkerton)
Subject: Re: Computer Virus (Future Processors)

>
>As I recall, the Command and Data Systems (CDS) computer(s) on Magellan
>and Galileo are rad-hard, CMOS RCA 1802 chips.  There was talk at the
>time (about 4 years ago) about moving to 8086-type processors
>manufactured by Harris (again, rad-hard requirements).

Portions of the Mars Observer Spacecraft are still hoping to use that
elusive Harris 80C86RH (Rad Hard) - I think it is planned to be a
5 Mhz part.

>
>Of course, this would make it really easy to use IBM PCs, running
>MS-DOS, to do development.  Given larger memories coming, and standard
>tools to play with, one could imagine writing routines in "C" and doing
>final unit testing of the code on the PC, taking the resulting
>binaries, and integrating it into the spacecraft computer.
>

Only the most generic, and stand alone type testing will be done this
way.  I/O and interrupt processing being so different in the actual
flight computers.

>
>A more serious question:  what will be used for computing power on such
>probes in the near future?  Is it Harris or what?

Probably the Harris 80C86RH, there probably is a Mil-Std-1750A type of
a computer that is going rad-hard (I don't know of one in particular,
just speculation), and I've heard that there is a large effort to get
a rad hard 80386 available (I think this is being done to support
Space Station efforts).

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

Date: 27 Oct 89 23:57:24 GMT
From: henry.jpl.nasa.gov!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: KSC Payload Update (Forwarded)

DAILY STATUS/KSC PAYLOAD MANAGEMENT AND OPERATIONS 10-27-89


- STS-31 HST (AT VPF) -

GSE CONFIGURATION SETUP FOR BATTERY CHARGING HAS BEEN COMPLETED.
DUE TO A PROBLEM ESTABLISHING THE HST SINGLE POINT GROUND,
BATTERY CHARGING AND THE HST FUNCTIONAL TESTS HAVE BEEN DELAYED.
PERSONNEL ARE SUPPORTING THE CONTINUOUS VPF ENVIRONMENTAL AND ECS
UNIT MONITORING.  ACCESS PLATFORMS AND THE HST FLYING CARPET
HAVE BEEN REMOVED FROM THE VPF.

- STS-35 ASTRO-1/BBXRT (AT O&C) -

AFTER REMOVAL OF A MICROSWITCH, A 0.156 INCH DIAMETER VIDEO PROBE
WAS USED TO AID IN THE SEARCH FOR THE MISSING WASHER.  THE WASHER
WAS LOCATED IN THE PGSA-1 MOTOR AREA AND EVALUATION IS ACTIVE TO
DETERMINE THE METHOD OF RETRIEVAL.  MUE INSTALLATION AND RPA
CHECKS ARE ACTIVE.

- STS-40 SLS-1 (AT O&C) -

RACK 7 AND 10 STIFFENER MOD ACTIVITIES HAVE BEEN PLACED ON HOLD
PENDING DESIGN CENTER RESOLUTION OF THE COUNTERSINK RIVET ISSUE.
PREPS FOR PROOFLOAD OF MVAK JOGGLE EQUIPMENT AND WATER SERVICING
GSE PREPS AND VALIDATION ARE IN WORK.

- STS-42 IML (AT O&C) -

ECLS CLOSEOUT CAP VERIFICATION WAS COMPLETED.


 Ron Baalke                       |    [phone] x260
 Jet Propulsion Lab  M/S 301-355  |    [e-mail]
 4800 Oak Grove Dr.               |
 Pasadena, CA 91109               |

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

Date: 27 Oct 89 16:27:05 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: KH-11 or Lacrosse power sources?

In article <[e-mail]> [e-mail] (Peter D. Ashcroft) writes:
>I'd appreciate learning more about the power sources currently used by
>US satellites...

Essentially all solar arrays, usually large ones.

>... the power requirements on a passive sensor like KH-11
>would be even less (hence no need for RTGs)...

Um, RTGs are not high-power devices.  Their big virtue is nt high output
but lack of need for sunlight.

The KH-11 is undoubtedly solar-powered in any case, though.

>Any clues on how the power
>supplies of the USSR radar satellites compare to that of Galileo?

Virtually no resemblance.  Galileo uses plutonium-isotope RTGs.  The
Soviet radarsats use nuclear reactors fuelled with enriched uranium,
at vastly higher power levels.
--
A bit of tolerance is worth a  |     Henry Spencer at U of Toronto Zoology
megabyte of flaming.           | uunet!attcan!utzoo!henry [e-mail]

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

Date: 25 Oct 89 20:09:00 GMT
From: mailrus!shadooby!netnews.engin.umich.edu!caen.engin.umich.edu![e-mail]  (Nicholas A Contaxes)
Subject: Re: What would we do WITHOUT 'Freedom'?

In article <[e-mail]> [e-mail] (Walt Leipold) writes:
>In article <[e-mail]> [e-mail] (nick szabo) writes:
>>Our real space efforts--planetary exploration, new technology, microgravity
>>research, privatization, etc. etc.--do not at all rely on the Station.
>
>I tend to agree, but by now it's politically infeasible to change horses
>in midstream.

That position is at the root of why it costs ~ $6K/lb for us to get a load in
orbit via the shuttle (When the Challenger replacement cost is factored in, as
it should be.  That wasn't a one-time thing.  We can expect another loss within
4-5 years) when it costs the Russians ~ $300 - and why it is difficult to get
support for the space program.  Granted that educating the public is no over-
night job, with the budget deficits we're facing it may be the only way to
build a sound program.

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

Date: 27 Oct 89 15:46:31 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Asteroids as weapons of mass destruction

In article <[e-mail]> [e-mail] () writes:
>Take a small spacecraft out to about a light-year, aim it at Earth, and
> fire theengines.  When it hits, it should have a velocity close to c and
> would do a lot of damage.

If we assume "small" means 100 tons and that it is using chemical engines,
by the time it reaches a significant fraction of the speed of light there
will be about one atom of it left, and it can be treated as a cosmic ray.
Actually it's less than one atom if you do the mass-ratio calculations,
but it's difficult to subdivide atoms...

That is, a small spacecraft, using any immediate-foreseeable rocket
technology, will run out of fuel long before it can get anywhere near c.

There is no free lunch.  If you want to give a spacecraft enough kinetic
energy to do major damage when it hits something, that energy has to
*come from somewhere*.  Energy sources capable of driving spaceships to
significant fractions of the speed of light usually lend themselves to
weapons in much more direct ways.
--
A bit of tolerance is worth a  |     Henry Spencer at U of Toronto Zoology
megabyte of flaming.           | uunet!attcan!utzoo!henry [e-mail]

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

Date: 27 Oct 89 20:18:12 GMT
From: henry.jpl.nasa.gov!elroy.jpl.nasa.gov!forsight!jato!mars![e-mail]  (Ron Baalke)
Subject: Re: Asteroid Collisions

Here the names of two good science fiction books dealing with
asteroids impacting the earth:

      Lucifer's Hammer
      The Moon is a Harsh Mistress


 Ron Baalke                       |    [phone] x260
 Jet Propulsion Lab  M/S 301-355  |    [e-mail]
 4800 Oak Grove Dr.               |
 Pasadena, CA 91109               |

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

Date: 27 Oct 89 19:28:05 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 10/27/89 (Forwarded)

-----------------------------------------------------------------
Friday, Oct. 27, 1989                        Audio:  202/755-1788
-----------------------------------------------------------------

This is NASA Headline News for Friday, October 27th......

The space shuttle Discovery was moved from the Vehicle Assembly
Building to launch pad 39-B early this morning.  The STS-33
flight crew is scheduled to arrive at Kennedy Space Center
tomorrow, to participate in the Terminal Countdown Demonstration
Test Sunday and Monday.  They are scheduled to fly a classified
Defense Department mission around November 20.

NASA Administrator Richard Truly told the National Press Club in
Washington yesterday that the agency's analysis of future manned
missions to the moon and Mars "is proceeding exceedingly well."
Truly told a luncheon audience that while the missions "will be
technically demanding and not without risk, they are well within
our reach."

Aerospace Daily reports a series of options on program planning,
international cooperation and agency management for missions to
the moon and Mars will be presented to President Bush early next
year by the National Space Council.  An administration official
said NASA is putting together a "technical reference case" that
will provide program and mission planning scenarios, mission
alternatives, cost estimates and options for international
cooperation that the space council will use to prepare its
presentation to the President.  "We're not going to give the
President a plan that he simply selects, yes or no," the official
said.  "We're going to give him options in various areas to get
his guidance and input.  We see this as a planning process that
may go on for a year or more developing the details of it."

The Daily also reports that President Bush has received a revised
version of a national space policy first developed under the
Reagan administration and is expected to sign it shortly.  The
document will be a classified national security decision
directive, but will also be released in an unclassified version
as the first national space policy directive.


                        ***********


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

Wednesday, Nov. 1......

     2:00 P.M.         STS-34 crew news conference regarding the
                       recently completed mission to deploy the
                       Galileo spacecraft.

     2:30 (approx)     The quarterly "Aeronautics & Space Report"
                       will be transmitted.  It contains four
                       reports:  "Combating Malaria", "Voyager's
                       Last Encounter", "Better Airplane Wings"
                       and "Sights and Sounds of Space".

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 (LPC), NASA
Headquarters, Washington, D.C.

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

Date: 27 Oct 89 15:57:42 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Galileo Questions

In article <[e-mail]> [e-mail] (Will Martin) writes:
>... it seemed to be that lithium batteries were not allowed
>in payloads going up in the Space Shuttle, due to the risks of their
>exploding or outgassing or doing something else nasty. The Galileo probe,
>however, is powered by lithium batteries... ... was the restriction
>on lithium batteries only on *commercial* versions? ...

I think the real answer is that the restriction is on lithium batteries of
all kinds, unless NASA needs them really badly, in which case the rules
get bent.  You have to understand that Galileo is the peak of the aristocracy
of NASA payloads, whereas GetAway Special cans -- in which context the rule
was originally discussed -- are the scum of the Earth.

Remember too that almost all technology in Galileo is nearly a decade old,
since the thing has been in construction and test about that long.  Any
major new development in batteries for it has been available for quite
a while now.

>"T-minus" countdown chart included in the press kit listed a number of
>"built-in holds", such as the one at T-27 hours and so forth. Why is the
>countdown constructed this way? Why build in a "hold" of 8 hours instead
>of just lengthening the countdown period by 8 hours and scheduling the
>actions that take place during this hold at the same relative time?

This one probably deserves to be in the frequently-asked-questions list.
The answer, as far as I know, is that there is no particular reason for
this; it's just the way NASA's customs have evolved.  There needs to be
slack for handling minor problems, but there is no inherent reason why
the slack couldn't be scheduled with the clock running.  Undoubtedly it
would be necessary to make minor adjustments to procedures that have
come to assume that the countdown clock measures progress rather than
time, but nothing fundamental would be disrupted.
--
A bit of tolerance is worth a  |     Henry Spencer at U of Toronto Zoology
megabyte of flaming.           | uunet!attcan!utzoo!henry [e-mail]

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

Date: 30 Oct 89 02:50:40 GMT
From: calvin![e-mail]  (John Sahr)
Subject: Re: Trying to build a fluxgate magnetometer -- help!

In article <[e-mail]> [e-mail] (Doug McDonald) writes:
>>>I would like to measure changes at least as small as
>>>10 gammas (.001 Gauss), and if possible, even smaller.
>>?  You mean of course, nanotesla (nT), since 1954.  :-)
>I have been in the science business for over 20 years and have
>never heard anyone refer to magnetic fields in Tesla - everyone
>uses gauss. It is true that people know that someone somewhere
>created a unit of magnetic field called a Tesla, but no one
>remembers how many gauss are in one Tesla, and no one uses it.
>Sometimes it might appear in a textbook (usually directed at
>freshmen or sophmores - more advanced books use gauss).
[]
>Doug McDonald

Whoa, thea, padnuh.  The "Tesla" is alive and well, thank you.  If I walk
over to the High Volt Lab, I find people quite comfortable with kilogauss
or tesla (not the same, of course), as they torture innocent protons.

Engineering textbooks through the graduate level tend to use MKS units,
which include Tesla.  Physics textbooks, on the other hand, tend to use
cgs, which include gauss.  I have several of each brand of text. For
genuine pandemonium, look at plasma physics texts.  In ionospheric physics,
there is no standard at all, but a pretty free mix of cgs and MKS.  Chen's
plasma physics 1st ed was in cgs: the second is MKS.  You be the judge.

Actually, I prefer cgs all the way, myself, but I'm not dogmatic about it,
even though it ought to be obvious that cgs units are The One True Units.  On
the other hand, E/B in MKS has units of velocity, which is convenient.  But
on the other hand, E/B in cgs has no units at all, which is also convenient.
On the other hand, my Radio Shack voltmeter insists on giving me MKS units.
On the other hand, Jackson is a nice reference, and uses cgs, so it must be
good.

So, as I said, I don't insist upon cgs, because this is a free planet.

But, come the revolution, the MKSeoisie will be the first with
their backs against the wall.

--
John Sahr,                   | Electrical Engineering - Space Plasma Physics
[e-mail] | Cornell University,         Ithaca, NY  14853

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

End of SPACE Digest V10 #191
*******************