Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_5/V13_528.TXT

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Subject: SPACE Digest V13 #528

SPACE Digest                                     Volume 13 : Issue 528

Today's Topics:
           Re: Question about paint color for cars?
              Re: Why the space station?
        Re: Terraforming Mars?  Why not Venus?
        Star Trek NOT cancelled, message says
           Magellan Status for 05/08/91 (Forwarded)
              Astronaut Puppets
               Re: Saturn V and the ALS
              RE: SPACE Digest V13 #485
                Re: IT'S OVER
          [l/m 7/5] Reminders for Old Farts

Administrivia:

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

Date: 8 May 91 18:02:09 GMT
From: telxon![e-mail]  (Joe Staudt)
Subject: Re: Question about paint color for cars?

In article <[e-mail]> [e-mail] (Cyrus Shafai) writes:
>What paint color lasts the longest on cars?
>I have heard that red paint doesn't last too long, and that metallic paint doesn't
>do too well in the sun.

I have been told by body shop people that there are only two colors of car
paint that don't fade:  black and white.  I have never owned a black car, but
I have owned two white ones, and the paint does seem to hold up better than
other colors.  One caveat, however:  the road dirt that slowly embeds itself
into any car's paint is extremely visible on a white car.  I found that
periodic (at least semi-annual) treatments with a good cleaner/polish and a
lot of elbow grease would brighten the car's finish by several shades (it can
become nearly blinding on a good, sunny day 8-)).

Joe


--
Joseph Staudt, Telxon Corp. | ...!uunet!telxon!joes || [e-mail]
P.O. Box 5582               |
Akron, OH  44334-0582       | Heavy, adj.:
[phone] x3522        |       Seduced by the chocolate side of the force.

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

Date: 8 May 91 03:08:06 GMT
From: stanford.edu!agate!headcrash.Berkeley.EDU![e-mail]  (Frank Crary)
Subject: Re: Why the space station?

In article <[e-mail]> [e-mail] (Brian Yamauchi) writes:
>Why not put together a small (!) team of experts (technical personnel,
>not bureaucrats) from the various NASA centers (and perhaps other
>labs, companies, and universities, as well) to design a space station
>with clear goals in mind (orbital support of lunar/planetary
>exploration) -- with the only constraints being engineering, cost, and
>time?
>
>If this were done right, it might not even delay construction.  (Is
>first element launch still scheduled for 1995?)  In fact, given the
>remaining budget ($26 billion) and time (nine years to PMC) of the
>current station, I would be surprised if such a team couldn't come up
>with a station that was much better suited to the goals of space
>exploration.
Since the only reason the Shuttle (as opposed to a Titan) is needed to
build Freedom, a quick-and-dirty construction shack in orbit would
reduce the cost of building Freedom. Possibly, it might lower assembly
costs enough that the construction shack/Freedom combination would
be less than the cost of building Freedom alone with the shuttle. Such
a construction facility could use existing hardware (developed for Freedom)
and also be a testbed for the Freedom components.

                  Frank Crary
                  UC Berkeley

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

Date: 8 May 91 02:59:08 GMT
From: VAX1.CC.UAKRON.EDU!mcs.kent.edu!usenet.ins.cwru.edu!agate!headcrash.Berkeley.EDU![e-mail]  (Frank Crary)
Subject: Re: Terraforming Mars?  Why not Venus?

In article <[e-mail]> [e-mail] (Fraering Philip) writes:
>Actually, the reason Mars is a better thermal enviornment (_IF_) heat
>buildup rather than freezing is a problem, is that the permafrost
>makes one hell of a heat sink.
>
In suit design, heat build up is ALWAYS a problem. The human body is a
200 to 800 watt heat source which is VERY sensitive to temperature
change. All current or past suits slove the problem of wide temperature
ranges by insulating like hell, then removing the ~500 watts the body
produces.

>The martian atmosphere is too thin to do that much about heat
>transfer;
>
Not so, given the wind velocities, and the forced convection they provide
you can dump well over the 800 watts (maximum) produced by the body.

>How much does the cooling system on a skintight weigh? And isn't
>carrying around the extra mass of a space suit in gravity going to be
>harder than in zero gravity?

The idea of a skintight suit (the Space Activity Suit was the name of the
only real design, and didn't work too well.) is all about how the pressure
is maintained. It has nothing to do with thermal control.
The cooling system in today's spacesuit drives the mass of the Portable
Life Support System (PLSS). Without the need to cool the suit, the PLSS
could weigh under 30kg, compaired to the current Shuttle suit's 73kg.

Carring the weight of a spacesuit on Mars (~1/3 g's) would be REAL
hard. We (E.g. NASA/Ames and the UC Berkeley Mechanical Engineering Dept.)
are working on designs for Mars suits. The biggest driving requirment
is to lower the suit weight. (We are targeting the WEIGHT of the lunar
suits (from Apollo) on the moon.) To get the weight this low, we are
hoping to use a passive cooling system (e.g. dumping heat to the
maritian environment without a air conditioner on the astronaut's back.)

                      Frank Crary
                      UC Berkeley

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

Date: 8 May 91 10:11:24 GMT
From: mcsun!unido!mpirbn![e-mail]  (Daniel Fischer)
Subject: Star Trek NOT cancelled, message says

Date: Mon, 6 May 91 11:29:46 -0600
From: Gym Z. Quirk <[e-mail]>
Organization: University of New Mexico, Albuquerque

In article <[e-mail]> you write:
>STAR TREK THE NEXT GENERATION WILL BE CANCELLED AFTER THE 1991-92
>SEASON. IT IS OFFICIAL FROM THE PRODUCERS OF THE SHOW.
>a) Is that true?
No.
>d) How popular was TNG after all in the U.S., compared to TOS, soap & sitcoms?
TNG is the #1 non-game show in syndication.
---
You have fallen victim to what is termed "Flame bait".  Some idiot has
taken it upon himself to make himself feel superior to others by
attempting to ruffle the feathers here in rec.arts.startrek.  It
happens every month or so.  (Actually, we've been overdue...;-)
In essence, disregard the above and enjoy the show.
--
Capt. Gym Z. Quirk  net.terrorist (reformed) |  This space
[e-mail]                       | intentionally
(Known to some as Taki Kogoma)               |  left blank

As no message of this kind was on either group by now, I thought posting this
personal message by someone else is justified - another poster in sci.space,
e.g., had already believed in the original story...

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

Date: 8 May 91 22:23:51 GMT
From: [e-mail]  (Peter E. Yee)
Subject: Magellan Status for 05/08/91 (Forwarded)


                     MAGELLAN STATUS REPORT
                           May 8, 1991


     The Magellan spacecraft, now just seven days from
completing its first cycle of Venus mapping, is continuing its
successful performance. All of the communications margins,
spacecraft temperatures and power levels continue to be within
the expected range.

     The present thermal environment requires Magellan to shade
the equipment bus with the high-gain antenna for two 36-minute
periods in each orbit. It also requires the solar panels to be
pointed 45 degrees away from the normal attitude to reduce excess
electrical power.

     The strategy cuts about 15 minutes from each mapping pass,
ending each image swath at 7 degrees north latitude.

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

Date: 6 May 91 17:49:58 GMT
From: dino.qci.bioch.bcm.tmc.edu![e-mail]  (Timothy B. Reynolds)
Subject: Astronaut Puppets

About 8 months ago I did a posting asking if anyone remembered one of the
networks doing a moonwalk simulation with pupets during the apollo program.
Many of you sent be small bits of information and the result is, I have
found them after ten years of searching. I would like to thank all of you
that e-mailed me with info. Now all I have to do is get the owner to sell
me one of them....
Thanks again to all of you that helped.

Tim

--
Disclaimer: My opinions are my own, not HHMI's or Baylor College of Medicine
------------------------------------------------------------------------------
"And we stand and watch the gods and idols fall, as the blameless ones go
 blindfold to the wall"                                  Robin Trower....

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

Date: 8 May 91 20:02:36 GMT
From: aio!icarus.jsc.nasa.gov![e-mail]  (Brad Mears)
Subject: Re: Saturn V and the ALS

In article <[e-mail]>, [e-mail] (Greg Hennessy) writes:
|> In article <[e-mail]>
|> [e-mail] (/dev/null) writes:
|> then you lose. I don't have to prove that ALS won't work. You have to
|> prove it will, at least before you expect to have large sums of money
|> given to it. Since the track record so far is an expensive launch
|> system that does not meet promises, it is nearly *impossible* to trust
|> you again.

Your attitude is very understandable, but you left something out.  How can
NASA regain the trust of the general public (or even Congress)?  Presumably,
the only way to regain your trust is to build a launch vehicle that fulfills
the promises made for it.  But we can't build another launch vehicle because
we failed once.  Catch-22.

You say that we have to "prove" that ALS will work.  HOW?  How do you PROVE
it without building it?

This isn't a flame.  It is a serious question.  How can NASA shake the bad
rep it got over Shuttle?  You'll get no argument from me on the expense of
Shuttle.  Mistakes were made.  But don't condemn NASA forever or we'll never
get anything built.

IMHO, everbody learned something from Shuttle.  I think NASA and Congress both
realize they share responsibility for the Shuttle's shortcomings.  If this is
the case, don't you think it is time to move on?  If it isn't the case, what
else needs to be done?

--
Brad Mears
[e-mail]

----------------------------------------------------------------------------
Opinions are expressly forbidden.  | "It is better to die on your feet
I speak for myself and no other.   |  than live on your knees"
                                   |                    - Dolores Ibarruri
----------------------------------------------------------------------------

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

Date: 7 May 91 05:35:01 GMT
From: bonnie.concordia.ca!news-server.csri.toronto.edu!torsqnt!hybrid!torag!w-dnes![e-mail]  (Walter Dnes )
Subject: RE: SPACE Digest V13 #485


[e-mail] (AMON) writes:

>
> Re: Tethers
>
> The analysis of tethers stating problems with angular momentum and saying
> it wouldn't work, TAANSTAFL, missed the point.
>
> The purpose of tether climbing is not that you gain anything for free, but
> that you borrow energy when climbing and return it, less entropies bill
> when you leave. You save on the fuel required to get to the higher orbit
> and fuel required for reentry, which translates into payload and lower
> per pound costs.
>
     This is starting to get interesting. I assume that we're not
*REALLY* "borrowing" energy from the future. I believe that the
correspondent is trying to say that a departing crew would exit at
the same time as a fresh crew arrives. Thus the centre-of-mass of
the main-space-station-plus-one-shuttle would be preserved.
Presumably...
     - a downward boost would be required for the old crew's shuttle
     - the tether will be unreeled, letting down the old crew's shuttle
     - causing the main space station to move higher
     - the tether would spin a generator to recharge fuel cells
     - meanwhile, the new crew flies up to the bottom of the
       tether in their shuttle
     - at the exact moment that the new crew's shuttle grabs the tether
     - the old crew's shuttle releases its grip on the tether
     - and drops into an eliptical orbit whose perigee grazes the
       atmosphere sufficiently to allow air-braking and a return to
       earth without having to consume rocket fuel.
     - meanwhile the new crew will be reeled in by an electric motor
       powered by the fuel cells that we recharged ( "plus entropy" )
     - after reeling in the new crew, the space station would have
       dropped back down to its original altitude

     I wonder how often several thousand miles of tether can be reeled
in and out without stress failure. We haven't even begun to consider
the longterm effects of micrometeorite bombardment on the structural
integrity of the tether.

> If the payload UP exceeds the payload DOWN, there is a net loss which can
> also be made by using the tether to steal energy from the Earth's magnetic
> field.                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  ^^^^^^

     If you think I'm being rough on you, try posting that sentence
in the sci.skeptic newsgroup. Someone new comes up with that every
couple of weeks, either to power a flying saucer or a perpetual
motion machine. Gives the flame-throwers something to chew on.

>     Charged tethers can act as either generators or motors depending on
> how you use them, and allow you to move up or down in orbit at will, albiet
> slowly.

     Whoa... you can *CONVERT ORBITAL ENERGY TO ELECTRICAL ENERGY*.
If you've got humungous solar panels you could conceivably generate
lots of electricity and *CONVERT ELECTRICAL ENERGY TO ORBITAL ENERGY*.
The solar panels could only operate half of the time. They should
double  as "solar sails" from "satellite noon" to "satellite midnight".
From "satellite midnight" to "satellite noon" the space station is
heading into the solar wind. During that time, the panels should be
oriented to present a minimal profile to the sun. I could see micro-
meteorite pitting reducing the efficiency of the solar power unit
over time.
     Given that 99% of the mass of the space station would consist of
several thousand miles of tether, drums to wrap that tether around,
electrical motors to turn the drum, and solar panels to power the
electrical motors, is there going to be any room for people ? Also,
what would the maintenace needs of such a complex setup be ?

-----------------------------------------------------------------------------
[e-mail]    -- or --   [e-mail]
hybrid!torag!w-dnes!waltdnes  <--- The hard way
[e-mail]     <--- Compuserve

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

Date: 9 May 91 04:22:30 GMT
From: prism![e-mail]  (Matthew DeLuca)
Subject: Re: IT'S OVER

In article <[e-mail]> [e-mail] writes:

>During the making of the show, I got into a long discussion with one of
>the consultants regarding the ins and outs of inescapable gravity
>fields, gravity propagation possibly exceeding the speed of light, etc. I
>wound up making a rather large cash bet that, once we are able to detect
>gravity waves, we would discover that they make a far less cluttered
>means of interplanatary communications ( and that we are more likely to
>detect another civilization using gravity wave communications than radio).

One question...does the ability to *detect* gravity waves imply the ability
to *generate* gravity waves?  From what little I know of the field, gravity
waves are thought to be generated primarily by supernovas...am I correct
in this assumtion?  I'm not sure I see how we are going to generate something
like that here on earth; if we have the ability to modulate gravity (which
I assume we would have to do to make use of it as a communications medium,
other than a Morse-like code) we're going to be able to do a heck of a lot
more with it than communicate...

--
Matthew DeLuca
Georgia Institute of Technology      "I'd hire the Dorsai, if I knew their
Office of Information Technology      P.O. box."  - Zebadiah Carter,
Internet: [e-mail]    _The Number of the Beast_

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

Date: 9 May 91 11:01:23 GMT
From: eagle!data.nas.nasa.gov!amelia![e-mail]  (Eugene N. Miya)
Subject: [l/m 7/5] Reminders for Old Farts

Hints for old users (subtle reminders) You'll know these.

Minimize cross references, [Do you REALLY NEED to?]
Edit "Subject:" lines especially if you are taking a tangent.
Send mail instead, avoid posting follow ups. [1 mail message worth 100 posts.]
Internet mail readers: send requests to add/drop to SPACE-REQUEST not SPACE.
Read all available articles before posting a follow-up. [Check all references.]
Cut down attributed articles.  Summarize!
Put a return address in the body (signature) of your message (mail or
article), state institution, etc. don't assume mail works.
Use absolute dates.  Post in a timely way.  Don't post what everyone will
get on TV anyway.
Some editors and window systems do character count line wrapping:
please keep lines under 80 characters for those using ASCII terms (use <CR>).

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

End of SPACE Digest V13 #528
*******************