Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_4/V16NO453.TXT

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Date: Tue, 13 Apr 93 05:00:07
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #453
To: Space Digest Readers
Precedence: bulk


Space Digest                Tue, 13 Apr 93       Volume 16 : Issue 453

Today's Topics:
                    Administrivia from Bill Gawne
Acceptable metric conversions (was Re: Pioneer Venus Last Findings) (2 msgs)
              Blow up space station, easy way to do it.
              Clementine Science Team Selected (3 msgs)
                          fairly new program
                             Gemini Suits
        Mir 2's planned orbit [was Re: Degrees vs. experience]
          New aircraft TU-154M for leasing, set spare parts.
                    Potential World-Bearing Stars?
                        Quick reaction shuttle
                Shuttle oxygen (was Budget Astronaut)
                          Shuttle questions
                            Space Spinoffs
                  SSTO vs high performance aircraft
          Two Stage Aircraft (was Why is SSTO  Single Stage)
                 Vulcan?  No, not Spock or Haphaestus
                   Why is SDIO doing "Clementine"?

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

Date: Mon, 12 Apr 1993 18:47:59 GMT
From: William Charles Gawne <[e-mail]>
Subject: Administrivia from Bill Gawne
Newsgroups: sci.space,sci.space.shuttle

Hi there sci.space readership.  Just wanted to announce that I'll be
posting from this address for a while.  Yes, I still work at the same
place and all that, but for a variety of reasons I prefer to post from
this address.

-Bill Gawne

 "Forgive him, he is a barbarian, who thinks the customs of his tribe
  are the laws of the universe."                       - G. J. Caesar

e-mail: [e-mail] (H)  OR  [e-mail] (W)
Any opinions are my own.  Nothing in this post constitutes an official
statement from any person or organization except me.

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

Date: 11 Apr 93 18:49:41 MDT
From: Andrew Folkins <[e-mail]>
Subject: Acceptable metric conversions (was Re: Pioneer Venus Last Findings)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Bill Higgins-- Beam Jockey) writes:
> In article <[e-mail]>, [e-mail] (Andrew Folkins) writes:

[Lots of numerically-silly conversions deleted]

>> Maybe we should send the PR crew back to Introductory Physics and teach them
>> about significant digits, or at least take their calculators away...
>
> Andrew, you have pointed out the problem very well.  Now for your
> homework, imagine you are the boss of Public Affairs for a NASA
> center.  Write guidelines, in 300 words or less, which will guarantee
> that your employees will always produce acceptable English-to-metric
> and metric-to-English conversion figures in their press releases.
>
> Bill Higgins, Beam Jockey

Well, being a "bi-standardized" Canadian who knows perfectly well that 80
degrees Farenheit and 25 degrees Celsius (or 300 K ;-) are close enough,
(but still can't remember the conversions between teaspoon, tablespoon,
ounce, fluid ounce, cup, quart, pint, Imperial gallon, and U.S. gallon) how
about:

"Use an equal number of significant digits in both the original and
converted values, unless the conversion happens to be less than ten and
close to a simple fraction (i.e. one-half or one-quarter).  If you are
specifying a range of values, use the same number of significant digits in
both values. In addition, if the original value is an approximation, use
that same implied accuracy in a conversion."

(Hmm, maybe we should just ship that last sentence off to them.)

Thus, we get:

>>>>25 and 75 feet deep (762 and 2286 centimeters).
   (God grief, I missed that the first time - CENTIMETERS???)
   25 feet -> 7.62 metres -> 7.5 metres -> 8 metres (because it's a range)
   75 feet -> 22.86 metres -> 23 metres

Now, "25 to 75 feet" sure looks like an approximation, so if we want we can
fudge 8-23 metres by about five feet/two metres, and we come up with 10-25
metres. It's a bit high, but in this case we've got a really rough initial
estimate anyway.

Similarly:

>>>>structures (1-60 miles in size (1.6-96 kilometers).
   ~= 2-100 km

>>>>Pioneer provided data from 80 to 210 miles (129 to 336 kilometers)
   ~= 130-340 km

>>>>kilometers) was more than 10 times denser and 2120 F (1,000 degrees Celsius)
   -> 1000C ~= 2000F

One additional point might be to say "25 to 75 feet (approximately 10 to 25
meters)", though using "approximately" all over the place might get a bit
tedious.

I doubt that my answer will cover all situations.  Hopefully, the PR
writers at NASA have the numeracy, common sense and journalistic freedom to
properly write conversions, and not have the process spelled out for them.
I'd hate to think that there's an offical NASA manual on how to write press
releases, and it includes a section saying "metric conversions of English
units shall include at least three non-zero digits."

Hey, does the gift shop at FermiLab sell hadrons?  McElwaine sent me some
COSMOSPHERE blueprints and I need about 5 pounds (2.273 kg) of them for the
main drive.

--
  Andrew Folkins  [e-mail]    [e-mail]
                  ...!cs.UAlberta.CA!ve6mgs!cuenews!andrew

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

Date: 12 Apr 93 14:35:41 -0600
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject: Acceptable metric conversions (was Re: Pioneer Venus Last Findings)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Andrew Folkins) writes:
> In article <[e-mail]>, [e-mail] (Bill Higgins-- Beam Jockey) writes:
>> Andrew, you have pointed out the problem very well.  Now for your
>> homework, imagine you are the boss of Public Affairs for a NASA
>> center.  Write guidelines, in 300 words or less, which will guarantee
>> that your employees will always produce acceptable English-to-metric
>> and metric-to-English conversion figures in their press releases.
[...]
> how about:
>
> "Use an equal number of significant digits in both the original and
> converted values, unless the conversion happens to be less than ten and
> close to a simple fraction (i.e. one-half or one-quarter).  If you are
> specifying a range of values, use the same number of significant digits in
> both values. In addition, if the original value is an approximation, use
> that same implied accuracy in a conversion."
>
> (Hmm, maybe we should just ship that last sentence off to them.)

Thanks; now you are part of the solution instead of just a complainer...

> I'd hate to think that there's an offical NASA manual on how to write press
> releases, and it includes a section saying "metric conversions of English
> units shall include at least three non-zero digits."

But ths suspicion lingers, doesn't it?

> Hey, does the gift shop at FermiLab sell hadrons?  McElwaine sent me some
> COSMOSPHERE blueprints and I need about 5 pounds (2.273 kg) of them for the
> main drive.

We sell coffee mugs, hats, t-shirts, and sweatshirts made from 100%
recycled hadrons (some leptons have been added as a preservative).
The gift operation has the misfeature that it's only open weekdays,
though we probably get more visitors on weekends.

Have you tried Federation surplus?  (See the signature quote.  It's
from last week's episode.)  Baryons are members of the hadron
family...

Bill Higgins, Beam Jockey              | "Captain's Log, Stardate 46682.4.
Fermi National Accelerator Laboratory  | The *Enterprise* is docked at the
Bitnet:           [e-mail]  | Remlar Array, where it will undergo
Internet:       [e-mail]  | a routine procedure to eliminate
SPAN/Hepnet:           43011::HIGGINS  | accumulated baryon particles."
("Baryon Bunnies" under the beds?)     | Hmm, my apartment needs this too.

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

Date: Mon, 12 Apr 1993 14:07:18 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: Blow up space station, easy way to do it.
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:

>> [LLNL inflatable is assembled without spacesuits.]

>Shipping the module with packaged HVAC is a must, but how do they
>handle power,

Batteries and amorphous solar cells. They can operate life support long
enough for assembly.

>and how long is "long enough" given the vagaries of
>launch schedules and assembly difficulties? Having modules that
>can remain partially assembled in orbit for unscheduled months of
>delay is pretty much a must at the present state of the art.


Assembly does not begin until the assembly crew is present. The
station is inflated, begins to rotate, and then assembly begins.

>It's instructive to look at the differences between blimps and
>dirigibles when examining these station ideas.

Absolutely. That's why LLNL had a maker of such vehicles pass
on their design. This company also has made all of NASAs' post-
apollo spacesuits so they have space experience. The company (ILC
Dover) said the design was doable.

  Allen

--
+---------------------------------------------------------------------------+
| Lady Astor:   "Sir, if you were my husband I would poison your coffee!"   |
| W. Churchill: "Madam, if you were my wife, I would drink it."             |
+----------------------65 DAYS TO FIRST FLIGHT OF DCX-----------------------+

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

Date: 12 Apr 1993 13:58:16 GMT
From: John F Carr <[e-mail]>
Subject: Clementine Science Team Selected
Newsgroups: sci.space,sci.astro

In article <[e-mail]>
    [e-mail] (Matthew DeLuca) writes:

>>    Clementine, sponsored by the Strategic Defense Initiative Office
>>(SDIO), will launch a small spacecraft in January 1994 to orbit the moon for
>>several months, then de-orbit the moon in early May 1994.
>
>Um, where do they plan to land the moon? :-)

Since it's an SDI project, obviously they plan to land it on foreign
missile silos, but I think it would be less destructive if they just
aimed the moon to intercept the ICBMs in flight.

To support this project the next nuclear proliferation treaty will
require 2 years advance notice of all hostile missile launches so
that the USA has time to move the moon onto an interception course.

--
    John Carr ([e-mail])

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

Date: Mon, 12 Apr 1993 14:48:34 GMT
From: "Doug S. Caprette Bldg. 28 W191 x3892" <[e-mail]>
Subject: Clementine Science Team Selected
Newsgroups: sci.space,sci.astro

In article <[e-mail]> [e-mail] (Matthew DeLuca) writes:
>In article <[e-mail]> [e-mail] (Ron Baalke) writes:
>
>>    Clementine, sponsored by the Strategic Defense Initiative Office
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>(SDIO), will launch a small spacecraft in January 1994 to orbit the moon for
>>several months, then de-orbit the moon in early May 1994.
>

Why is a civilian project being spoinsored by a military agency?

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

Date: Mon, 12 Apr 1993 19:31:23 GMT
From: Henry Spencer <[e-mail]>
Subject: Clementine Science Team Selected
Newsgroups: sci.space,sci.astro

In article <[e-mail]> [e-mail] (Doug S. Caprette Bldg. 28 W191 x3892) writes:
>>>    Clementine, sponsored by the Strategic Defense Initiative Office
>                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>>(SDIO), will launch a small spacecraft in January 1994 to orbit the moon for
>>>several months, then de-orbit the moon in early May 1994.
>
>Why is a civilian project being spoinsored by a military agency?

Why do you assume it's a civilian project?  It's not.  Clementine is
a military technology-test mission that happens to be pointing its
sensors at unclassified targets of civilian interest.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

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

Date: 12 Apr 1993 15:34:49 GMT
From: Steve Spicklemire <[e-mail]>
Subject: fairly new program
Newsgroups: sci.space

Hi,
    We are starting a new initiatitive at the University and I have a
couple of questions!

(1) We want to buy a reasonably good (fairly portable, e.g., by three
students and a pick-up) reflector for student use. We have about $4k and
are interested in any recommendations you experienced folk might have.

(2) We have about $6k to update our machine shop. I'm looking for
brand-names, mail order info etc. for a table-top sized lathe (new or
used) a drill-press/mill (heavy duty drill press with a three way
precision table), and some sheet metal tools. Any suggestions where to
look for this kind of stuff?


Thanks!
-steve

--------------------------< cut here >----------------------------
Steve Spicklemire [phone]             [e-mail]
Physics and Earth-Space Science                     NeXTmail Welcome!
1400 East Hanna Avenue, 46227

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

Date: 12 Apr 93 09:58:54 EDT
From: Chris Jones <[e-mail]>
Subject: Gemini Suits
Newsgroups: sci.space

In article <[e-mail]>, flb@flb ("F.Baube[tm]") writes:
>From: Pat <[e-mail]>
>> Subject: Budget Astronaut (was: Idle Question)
>>
>> The gemini suit must have been tolerable,  i think on emission
>> went 2 weeks,  but were they in suits the whole time?
>
>As I recall, they were for the first few missions,
>that weren't of such long duration, but that after
>a few missins without problems, they took the luxury
>of doffing their suits for periods of time.  I think
>that going without suits was a first, at least for
>Americans; there was discussion on the Tube of what
>would happen and what the astronauts would do in
>the event of a sudden loss of cabin pressure.

The 10 Gemini missions consisted of one 5 hour flight, one 8 hour flight (I
think--Gemini 8), one one day flight, three three day flights, two 4 day
flights, one 8 day flight, and one 14 day flight.  I think the astronauts may
have removed their helmets on several of the missions, but the only flight on
which they removed their suits was Gemini 7, the 14 day mission.  That was also
the only flight on which they flew special, light-weight suits, presumably
designed for ease of doffing and donning.  They were weird looking -- the
helmet looked like an inflated cloth bag with a plastic visor in the front.

The missions' length ramped up rather quickly, actually.  Gemini 4 (the second
manned flight) was 4 days, Gemini 5 was 8 days, and Gemini 7 (which followed
Gemini 5 -- Gemini 6 came during this mission) was 14 days.  After
demonstrating that manned flights longer than the planned lengths of the lunar
landing missions were possible, the program concentrated on rendezvous and
docking flights, which were of shorter duration.

--
Chris Jones    [e-mail]

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

Date: 12 Apr 93 09:43:28 EDT
From: Chris Jones <[e-mail]>
Subject: Mir 2's planned orbit [was Re: Degrees vs. experience]
Newsgroups: sci.space

In article <1q7v8f$[e-mail]>, prb@access (Pat) writes:
>
>Dont the russians have a third launch facility, at kapustin yar??????
>what republic is that in?   is it also unable to do proton work?

They did -- it's been reported closed.  It is (was) in Russia.  Let alone
Proton work, I don't think it ever launched anything like an "A" class rocket
(Sputnik, Vostok, Soyuz, Molniya).  I recall it was used for the Cosmos
launchers.

>What's the status of cape york,  is that going up still?

Was it ever going up?  I wasn't aware it had gotten past the talking stage.

>CY  should be able to hit 51 degrees  just as easily, or am i betraying
>a shocking ignorance of  orbital mechanics.

Certainly Kapustin Yar could have put satellites into a 51 degree orbit.  I'm
not aware of what was in the area, but a desire to avoid dropping spent stages
into populated areas may have constrained the usable orbits.
--
Chris Jones    [e-mail]

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

Date: Mon, 12 Apr 1993 14:56:59 GMT
From: "David J. Morton" <[e-mail]>
Subject: New aircraft TU-154M for leasing, set spare parts.
Newsgroups: misc.forsale,misc.invest,misc.jobs.contract,rec.aviation,sci.space

In article <[e-mail]>, [e-mail] (Larion Tyshler) writes:
>In article <[e-mail]> [e-mail] (gozdz,antoni s) writes:
>>In article <[e-mail]> [e-mail] writes:
>>>Category: Offers to leasing
>>>Headline: New Aircraft TU-154M
>>>
>>>
>>
>>Mr. Director Agabalaevich:
>>
>>No bombs included?! what a rip-off... I'll pass this one.
>>
>>--T.
>>
>>BTW, are these guys out of their [....] minds, or was
>>our propaganda so effective that they believe some
>>netters could actually buy such stuff and land in
>>their driveway? Too much soda pop, too quick...
>
>
>You *WANT* bombs?  Just ask!
>
  BOMBS?
Go look up Tu 154M, it should be in most AIRLINER hand-books.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Sgt. D.J. Morton            Environmental Resource Sciences
Hastings and Prince Edward Regiment    Trent University
                    Peterborough, Ontario
                    K9J 7B8  Canada

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

Date: Mon, 12 Apr 1993 19:52:23 GMT
From: Daniel Appelquist <[e-mail]>
Subject: Potential World-Bearing Stars?
Newsgroups: sci.space

I'm on a fact-finding mission, trying to find out if there exists a list of
potentially world-bearing stars within 100 light years of the Sun...
Is anyone currently working on this sort of thing?  Thanks...

Dan
--
Daniel K. Appelquist|QUANTA is the electronically published and distributed
[e-mail]       |magazine of science fiction  and  fantasy.   For  more
703-758-2712        |information, send  mail to  [e-mail] or,
703-758-0233 (Fax)  |for back issues, ftp export.acs.cmu.edu, id:anonymous.

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

Date: Mon, 12 Apr 1993 20:32:49 GMT
From: Josh Hopkins <[e-mail]>
Subject: Quick reaction shuttle
Newsgroups: sci.space

[e-mail] (Pat) writes:

>(Josh Hopkins) writes:
>|(Pat) writes:
>|
>|>Keep her in the VAB  tipped up with a canadaarm, and ready to go,
>|>or  in the OPF  ready for a cargo mission.
>|
>|Pat, you can't _do_ that.  If you could fly shuttles as "rapid reaction"
>|vehicles, or fly them economically with half the payload capacity we wouldn't
>|need new launchers. Okay, that's a little too generous, but I think you get the
>|drift.  Doing what you want to do is fundamentally impractical with the hardware
>|you're talking about.

>Why not.

>THe reason, shuttle missions take so long, is the manifest is full.

Huh?

>The Intelsat rescue,  took  some 2 odd years, because they
>needed a shuttle available,  and even that took a lot of
>schedule juggling.

There certianly is some truth to that.  However, keep in mind that there's more
to orbital operations that tossing up some guys with space suits and a robot
arm.  The Intelsat mission (or the Hubble mission) required significant amounts
of training and some new hardware.  The astronauts are not going to just go
up and improvise.

How difficult can it be to keep a
>shuttle stacked,  and waiting for the occasional light weight
>mission?

Try impossible.  Or at least, not practical for the amount of money we're
willing to spend.  For one thing, you'd be tying up a launch pad or VAB spot.
For another, the shuttle doesn't have an infinite shelf life.  You can't keep
the fuel in it forever (or the food for that matter).  For another, there are
things to do before launch besides counting backwards.  The arrangements must
be made for landing, the weather must be predicted and you must schedule a
slot in the cape launching schedule to make sure that Columbia and some Delta
aren't trying to share the same airspace at the same time.

If you could find an important mission that didn't require any new hardware or
training, and had to be performed within, say a year, but not within three
weeks of the word go, you might have a point.  However, I don't think there
are many.

>Look,  shuttles are already basically un-economical.  the fly because
>they have a guaranteed customer.  Sure,  OV-100  would only
>carry 20 Klbs, to orbit,  but for something like the Intelsat
>rescue,  why would it need any more.

>Or some of these  stranded comsats.  GD  stranded some bird in
>a low orbit, because of a wiring error a few years back.
>All it needed was someone to go up  and change a plug.

Pat, that was Intelsat.  If you examine the mission summary, you'll see that
there was more to the mission than changing a plug.


--
Josh Hopkins                                          [e-mail]
          "Tout ce qu'un homme est capable d'imaginer, d'autres hommes
                     seront capable de le realiser"
             -Jules Verne

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

Date: Mon, 12 Apr 1993 20:42:12 GMT
From: Josh Hopkins <[e-mail]>
Subject: Shuttle oxygen (was Budget Astronaut)
Newsgroups: sci.space

[e-mail] (Henry Spencer) writes:

>There is an emergency oxygen system that is capable of maintaining a
>breathable atmosphere in the cabin for long enough to come down, even
>if there is something like a 5cm hole in the wall that nobody tries
>to plug.

Wow.

Double wow.  Can you land a shuttle with a 5cm hole in the wall?
--
Josh Hopkins                                          [e-mail]
          "Tout ce qu'un homme est capable d'imaginer, d'autres hommes
                     seront capable de le realiser"
             -Jules Verne

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

Date: Mon, 12 Apr 1993 14:56:45 GMT
From: Paul Dokas <[e-mail]>
Subject: Shuttle questions
Newsgroups: sci.space

I was watching NASA Select on TV this morning (isn't cable wonderful :-/ )
and a couple of questions came to mind.

First, what they were doing this morning was preparing to close off one
of the O2 containers (number 4 I believe) because it was almost empty.
My question is, just how much gas (O2 or otherwise) is needed to support
a shuttle on a ~7 day mission?

After this, I began to wonder *how* the ground controller knew that
O2 container #4 was almost empty.  The obvious conclusion is that the
computer at his station told him so.  This leads to my next question:
how much data is being transmitted between the shuttle and the ground
controllers (in bytes per second)?  I know that the answer might be,
"It depends upon what is going on.  Sometimes there's a lot, sometimes
there's none."  So, what's the maximum amount of data that can be
exchanged between the shuttle and the ground?

Just curious
-paul

--
#include <std.disclaimer>
#define FULL_NAME                          "Paul Dokas"
#define EMAIL                              "[e-mail]"
/*            Just remember, you *WILL* die someday.             */

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

Date: Mon, 12 Apr 93 12:36:31 EDT
From: Tom <[e-mail]>
Subject: Space Spinoffs

[Michael asked what space spinoffs existed]

I suggested;
>>Again, it was inteneded, so it might not count as a spin-off, but how
>>about satellite based communication, like TV, Cellular phones, or Lorans?

>I don't think that TV is something that helps humanity.  And when I'm driving
>home seeing people talking on their phones instead of watching where they
>are going, I think that's anonther bad thing.

There are serious advantages, though, that may outweigh your disadvantages.
India has found a powerful educational media in TV, as have many around
the world, though India is quite activist with it.  Cellular phones,
besides turning driving time into productive time for many, can also
help with emergency situations.  Cellular phones are responsible also for
some bad driving arrests, as people call the cops to complain of
bad drivers, including license plates.  Rude truckers especially feel
this effect, from what I've heard around the Chicago area.

>What about the booming market for moon rocks?  I bought one when I was 7
>at the planetarium.

I'd count it as a spinoff, though it might get classified in the
nebulous, widespread 'educational' spinoff.  You were at a planetarium,
after all (Or were you there to see the Pink Floyd Laser Light Show? :-)

-Tommy Mac
-------------------------------------------------------------------------
Tom McWilliams 517-355-2178 wk   \\ As the radius of vision increases,
[e-mail] 336-9591 hm \\ the circumference of mystery grows.
-------------------------------------------------------------------------

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

Date: Mon, 12 Apr 1993 20:38:48 GMT
From: Josh Hopkins <[e-mail]>
Subject: SSTO vs high performance aircraft
Newsgroups: sci.space

[e-mail] (Phil G. Fraering) writes:

>[e-mail] (Josh Hopkins) writes:

>>[e-mail] (Bruce Dunn) writes:

>...
>>>The Voyager
>>>aircraft, which went around the world non-stop, was more or less the aircraft
>>>equivalent of an SSTO; something like 80 or 90% of the takeoff mass was fuel,
>>>and its payload - two people- was tiny (I don't have the actual numbers
>>>handy).  While it worked, a two stage system (or inflight refueling, which is
>>>in effect a two stage system), might be much more cost effective for airplane
>>>trips of this length.

>>As you pointed out, the reason we are trying SSTO technology is similar to the
>>reasons for flying Voyager (the aircraft).  The technology seems to be
>>available.  If it really does work, it _will_ be better than a multiple stage
>>rocket, so it makes sense to try and build one.

>>Of course, there is much more demand for a cheap
>>vehicle that can fly to orbit than there is for a vehicle that can fly non-stop
>>around the world.

>But there does seem to be a great demand for high-altitude drones with
>flight characteristics like Voyager (i.e. stay up for a week or so;
>relatively high lift at low speeds, etc...). If I'm not mistaken all
>of these things are one stage; I'm sure most of them are.

Actually, I'm aware of one such system that's _three_ stages. Seemed rather
complicated to me.  Long flight times can of course be achieved with payloads
larger that RPV class without resorting to staging.  There was a proposal for
a B36 with a nuclear reactor which would have been able to stay aloft almost
indefinately.


--
Josh Hopkins                                          [e-mail]
          "Tout ce qu'un homme est capable d'imaginer, d'autres hommes
                     seront capable de le realiser"
             -Jules Verne

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

Date: Mon, 12 Apr 1993 20:29:13 GMT
From: Thomas Clarke <[e-mail]>
Subject: Two Stage Aircraft (was Why is SSTO  Single Stage)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman)
writes:
> once you do, every field will have F1 stages sitting around waiting
> for an incoming DC-1/2 to relaunch.

This reminds me of the (only?) operational two stage aircraft:
the glider and its tow plane.

--
Thomas Clarke
Institute for Simulation and Training, University of Central FL
12424 Research Parkway, Suite 300, Orlando, FL 32826
[phone], FAX: [phone], [e-mail]

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

Date: Mon, 12 Apr 93 12:45:49 EDT
From: Tom <[e-mail]>
Subject: Vulcan?  No, not Spock or Haphaestus

>>Does anyone have any info on the apparent sightings of Vulcan?

>From memory Vulcan was an attempt to account for the precession
>of the axes of the orbit of Mercury in the late 19th century. The
>effect has now been full explained thanks to the Theory of
>Relativity. In fact Mercury's orbit was one of the first
>confermation of relativity. Vulcan was supposed to have been
>observed by a somewhat dubious 'gentleman' astronomer who kept
>his notes on a plank of wood, and used plane as an eraser.

Another legend with the name Vulcan was the planet, much like Earth,
in the same orbit, but on the other side of the Sun.  I don't know
the origin or age of this legend, though.  Maybe someone else can fill
in the people and time this legend comes from.

-Tommy Mac
-------------------------------------------------------------------------
Tom McWilliams 517-355-2178 wk   \\ As the radius of vision increases,
[e-mail] 336-9591 hm \\ the circumference of mystery grows.
-------------------------------------------------------------------------

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

Date: Mon, 12 Apr 1993 19:28:37 GMT
From: Henry Spencer <[e-mail]>
Subject: Why is SDIO doing "Clementine"?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Rudy J. Cazabon) writes:
>I have a question.  Why was SDIO given the necessary funding levels
>to conduct the "Clementine" fly-by of the Moon?

They were given the money for a sensor and navigation test.  A quick look
at the possibilities indicated that a Moon/asteroid mission was not much
harder than an Earth-orbit mission, would test the equipment as well if
not better, and would benefit both science and public relations.  So they
decided to do it that way.  (This is my reading of the situation, anyway.)

Note that Clementine 1 is *not* an optimized science mission by any
stretch of the imagination; only small details of the mission have been
tuned for best science return.  No proposal aimed primarily at science
would have left out a gamma-ray spectrometer, but that wasn't among the
technologies SDIO had money to test.

>I wonder if the funds and resources that SDIO has received for this mission,
>at least for the lunar and asteroidal fly-bys, would have been better
>spent by NASA in its attempt to fund the Lunar Resource Mapper and
>a proposed JPL micro-craft to go to an asteroid...

If we're fantasizing about ways that money could have been better spent,
I'd give it to Lunar Exploration Inc. for their Lunar Prospector mission.
That would give comparable science return much sooner than any NASA effort,
and rather better science return not much later than Clementine.  That sort
of approach would be far superior to giving it to NASA.

If we're discussing reality, bear in mind that:

(a) It is vanishingly unlikely that NASA could build and launch a
mission for what SDIO is spending on Clementine 1, never mind getting
it ready for launch next year.  SDIO has a huge advantage in being a
young agency not encumbered by too much red tape and bureaucratic fat.

(b) Congress has consistently balked at giving NASA *any money at all*
for lunar missions lately.  If you took that money away from SDIO, it
would not go to fund equivalent NASA efforts.

I would also note that the technologies SDIO is testing on this mission
have real potential for application to NASA missions.  Certainly the
Pluto Fast Flyby people are paying very careful attention.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

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End of Space Digest Volume 16 : Issue 453
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