Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_2/V16NO217.TXT

Internet Message Format | 1993-07-13 | 30KB

Date: Tue, 23 Feb 93 05:05:44
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #217
To: Space Digest Readers
Precedence: bulk


Space Digest                Tue, 23 Feb 93       Volume 16 : Issue 217

Today's Topics:
                 0891 : Betelgeuse fades!!! (2 msgs)
                        Canadian SSF effort ??
                           Galileo CD-ROMs
                  Getting people into Space Program!
          How many RPM's around his own axle can human take?
                       Instead of Fred.. ETCo?
      International Space Plasma Physics Summer School (update)
                    Mars Rescue Mission, what if!
                  Nobody cares about Fred? (2 msgs)
    Reliable Source says Freedom Dead, Freedom II to be developed
                     Sabatier Reactors. (2 msgs)
   Wouldn't an earth to moon shuttle be better than fred? (2 msgs)

    Welcome to the Space Digest!!  Please send your messages to
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----------------------------------------------------------------------

Date: Mon, 22 Feb 1993 20:03:11 GMT
From: Rob Douglas <[e-mail]>
Subject: 0891 : Betelgeuse fades!!!
Newsgroups: sci.astro,sci.space

In article <[e-mail]>, [e-mail] writes:
|> Betelgeuse has faded by a factor of two!!!
|>
|> Last time this happened was over four years ago.
|>
|>
|> -Tony Ryan,
|> "Astronomy & Space", new UK magazine, P.O.Box 2888, Dublin 1, Ireland.



Question::: What does this mean??  What causes this???

(please answer in as layman-like terms as possible)

thanks

ROB

--
==========================================================================
| Rob Douglas                       |  Space Telescope Science Institute |
| AI Software Engineer              |  3700 San Martin Drive             |
| Advance Planning Systems Branch   |  Baltimore, MD  21218, USA         |
| Internet: [e-mail]      |  [phone]   [338-1592 (fax)] |
==========================================================================

Disclaimer-type-thingie>>>>>  These opinions are mine!  Unless of course
    they fall under the standard intellectual property guidelines.
    But with my intellect, I doubt it.  Besides, if it was useful
    intellectual property, do you think I would type it in here?
--
==========================================================================
| Rob Douglas                       |  Space Telescope Science Institute |
| AI Software Engineer              |  3700 San Martin Drive             |
| Advance Planning Systems Branch   |  Baltimore, MD  21218, USA         |

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

Date: 22 Feb 93 20:30:11 GMT
From: Jeff Bytof <[e-mail]>
Subject: 0891 : Betelgeuse fades!!!
Newsgroups: sci.astro,sci.space

>In article <[e-mail]>, [e-mail] writes:
>|> Betelgeuse has faded by a factor of two!!!
>|>
>|> Last time this happened was over four years ago.
>|> -Tony Ryan,
>|> "Astronomy & Space", new UK magazine, P.O.Box 2888, Dublin 1, Ireland.

>Question::: What does this mean??  What causes this???

Red giants like Betelgeuse are long term variable stars, and some can
vary in brightness by many magnitudes.  The variability is probably
caused by oscillations in the energy production at the core of the store.
Nothing to be alarmed about.

-rabjab

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

Date: 22 Feb 93 19:45:32 GMT
From: "Kieran A. Carroll" <[e-mail]>
Subject: Canadian SSF effort ??
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (John F. Woods) writes:
>[e-mail] (Doug Mohney) writes:
>>In article <[e-mail]>, [e-mail] (Henry Spencer) writes:
>>>Clinton's probably just made some enemies at ESA, JSA, and CSA.  They've
>>>been angry enough when previous changes to Fred were made without any
>>>attempt to consult them, and now this...
>>>Unless this is handled very skillfully indeed, NASA is going to have real
>>>trouble lining up international "partners" for future projects.
>>Yet another "hidden cost" not mentioned by the chainsaw reformists.
>
>On the other hand, if the result is a station that can actually get *built*,
>and if that station can make use of the work done by the international
>partners, they may actually be relieved.  You can *bet* they've been skeptical
>about Freedom ever actually flying.

Actually, up here in Canada we've not been particularly
skeptical about whether or not could be built as designed.
Not, at least, based on technical grounds. Rather, there
has been skepticism about the ability of the U.S. Congress
to stick to their resolve (or at least to commitments made
by previous Congresses), and continue to fund the project
through to completion. Who'd have thought that the
Administration would be the one to try to pull the plug?
Although we have seen some of that in our own history---
a nice little fighter plane development program (the Avro Arrow)
was cancelled by a Conservative Prime Minister, soon after
taking office in the early 1960's, a move that was likely
motivated in part by the fact that the program had been started
by the previous (Liberal) government, and so was ideologically
impure. The present situation has a similar feel, as if the
main thing that Clinton has against SSF is that Reagan and
Bush supported it.
--

     Kieran A. Carroll @ U of Toronto Aerospace Institute
     uunet!attcan!utzoo!kcarroll [e-mail]

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

Date: Mon, 22 Feb 1993 19:01:00 GMT
From: "E. V. Bell, II - NSSDC/HSTX/GSFC/NASA - (301" <[e-mail]>
Subject: Galileo CD-ROMs
Newsgroups: sci.space,sci.astro,alt.sci.planetary,alt.cd-rom

In article <[e-mail]>, [e-mail] (Ron Baalke) writes...
>In article <[e-mail]>, [e-mail] (Ed McCreary) writes...
>>>>>>> On 22 Feb 1993 00:13 UT, [e-mail] (Ron Baalke) said:
>>
>>RB>      Five Galileo CD-ROMs (volumes 2 through 6) have been released by the
>>RB>Galileo project.  These CD-ROMs contains the raw images taken by the Galileo
>>RB> spacecraft on its Venus flyby in February 1990 and its first flyby of
>>RB> the Earth and Moon in December 1990.
>>
>>Stupid question, but why vol. 2-6?  Is a volume one going to be released
>>later?
>>
>
>Volume 1 was a test version.  It had a lot of errors in it, and will not
>be released.

    Actually, with apologies to Ron, Volume 1 will be forthcoming.
    From the letter distributed with the CD-ROMs:

    "You'll note that volume 1 is absent from this package. It was
    decided between the GLL Team and the PDS Imaging Node that it
    would be more valuable to have volume 1 produced after the
    Earth II and Ida encounters (next year). Volume 1 will therefore
    contain all cruise phase ancillary information - basically
    what is contained within the package described below, calibration
    data, catalog data and other TBD contents."

    Since the Earth II and Ida encounter will be some time in
    coming (1994 probably), volume 1 will be some time, too.

+------------------------------------------------------------------------------+
|  Dr. Edwin V. Bell, II    |  E-mail:                       |
|  Mail Code 633.9        |    (SPAN) NCF::Bell               |
|  National Space Science    |    or   NSSDC::Bell               |
|    Data Center        |    or  NSSDCA::Bell               |
|  NASA                |    or  NSSDCB::Bell               |
|  Goddard Space Flight Center    |   (Internet) [e-mail]       |
|  Greenbelt, MD   20771    |                           |
|  [phone]        |                           |
+------------------------------------------------------------------------------+

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

Date: 22 Feb 1993 13:26:32 -0500
From: Pat <[e-mail]>
Subject: Getting people into Space Program!
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Chris Jones) writes:
|In article <[e-mail]>, prb@access (Pat) writes:
|>
|>Seriously.  My point was that the X-15 was qualifying astronauts
|>at a rate that I think the SHuttle only passed recently.
|
|I don't think so.  I believe there were 99 X-15 flights TOTAL.  Not all of them
|went high enough to earn the pilot astronauts wings (most did not, I believe --
|if the mission was a "speed" rather than an "altitude" mission, it stayed low).
|Not every high altitude flight took a new astronaut up.  Going out on a limb, I
|bet the shuttle has made more international (i.e. non-US citizens) than the
   Ahem.  NASA has stated that no Citizens of any sort have been made
    on a shuttle flight :-)

    AS far as international astronauts.  sure.  The X-15 was a US
    program, unless a couple of brits or canadians snuck in somehow
    i'd bet they were all americans.  WHat I don't understand
    is why yeager never flew one of these.  I don't recall
    seeing him on the mission list.  Anyone have an answer for
    this?


|X-15 made in total.
|--
|Chris Jones    [e-mail]

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

Date: 22 Feb 93 19:59:19 GMT
From: Dick King <[e-mail]>
Subject: How many RPM's around his own axle can human take?
Newsgroups: sci.space,sci.med

In article <[e-mail]> [e-mail] (Frank Crary) writes:
>
>However, if the person is going to move around (or even turn his
>head), a _much_ slower rotation is required. Exactly how low
>would depend on the individual and how long he has to get used
>to it. (NASA studies suggest that people can adjust to up to
>3rpm within a few days). For an ammusement park, there wouldn't
>be any time to adjust. I don't know how slowly you would have to
>turn, but I suspect it would be under 1rmp.

There is a common amusement park ride in which the rider stands inside a 5-10m
diameter cylinder, back to the cylinder's inside wall, facing the axis.  The
axis is spun up to 5 or 10 RPM, and then it is tilted to near-horizontal.  The
rider is pressed against the inside wall of the cylinder by centrifugal force
of 2-3G, and is in no danger of falling, although the safety belt is wimpy at
best.

People commonly move their heads around -- at least i do.  You need to watch
yourself a bit when the axis is horizontal, because when you are at the top of
the now-tilted cylinder the centrifugal force is partially cancelled by gravity
but when you are at the bottom the centrifugal force is augmented, so you can
bump the back of your head a bit if you don't keep it under tight control.

Riders get a bit dizzy on this ride and others, but this is a lot more
acceptable -- even desirable -- in amusement park rides than in space stations.


-dk

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

Date: 22 Feb 93 18:22:14 GMT
From: Charles Chung <[e-mail]>
Subject: Instead of Fred.. ETCo?
Newsgroups: sci.space

OK, so Fred is once again on the Oprah Winfrey Diet Plan...


NASA's once again been asked to go back to the drawing boards, and I
can pretty much predict what's going to happen again during next
year's budget battle.  <sheesh>

What if NASA contracted the External Tanks Corporation for a space
station.  It won't do everything Fred will do.  But, my question is,
what can it do?  Will it suffice?  Let's just talk about its
technical merits, and just see if it's a possibility worth
considering.

-Chuck
---
*******************************************************************

    Chuck Chung                [phone] (O)
    Duke University Dept. of Physics    [phone] (H)
    Durham, N.C.      27706            [e-mail]

    "If pro is the opposite of con,
        then what is the opposite of progress?"

*******************************************************************

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

Date: Mon, 22 Feb 1993 11:02:34 GMT
From: Bo Thide' <[e-mail]>
Subject: International Space Plasma Physics Summer School (update)
Newsgroups: sci.astro,sci.electronics,sci.physics,sci.physics.fusion,sci.space,sci.research

                  Second announcement

          International Summer School on Space Plasma Physics

                  Organised by
       Radiophysical Research Institute, NIRFI, Nizhniy Novgorod, Russia
                      and
       Swedish Institute of Space Physics, IRFU, Uppsala, Sweden
                   to be held

    Onboard the Cruise Ship "Turgenyev" on the Volga River, 1-10 June, 1993

The purpose of the school is to give an introduction to the problems
of linear and non-linear space plasma physics, ionospheric modification,
the use of the ionosphere as a space plasma laboratory, as well as to
discuss current topics in astrophysics and ionospheric, solar, and
stellar plasma physics.

             List of lecturers and lectures

o Prof C E Alissandrakis, Greece, Emissions from Solar Flares.

o Prof A O Benz, Switzerland, Plasma Diagnostic of the Solar Corona
  using Decametric Radio Waves.

o Prof T Chang , USA, Electromagnetic Tornadoes in Space---Ion Cyclotron
  Resonance Heating of Ionospheric Ions; Lower hybrid collapse, caviton
  turbulence, and charged particle energization.

o Dr F C Drago, Italy, Radio Emission of Active Regions of the Sun and Stars.

o Prof G Dulk, USA, Radio Methods For Investigating the Solar Wind Between
  Sun and Earth.

o Prof Lev Erukhimov, Russia, Space Plasma Laboratories.

o Dr J Foster, USA, Scattering in the Ionosphere.

o Dr C Hanuise, France, Coherent Scattering in the Ionosphere.

o Prof M Hayakawa, Japan, Terrestrial Electromagnetic Noise Environment.

o Prof A Hewish, UK, Mapping Interplanetary Weather Patterns.

o Prof Yu Kravtsov, Russia, Polarisation and Wave Propagation Effects in
  Inhomogeneous Plasma.

o Prof J Kuijpers, Holland, Magnetic Flares In Accretion Disks.

o Dr Y Leblanc, France, Jupiter's Radio Emissions and Parameters the Plasma.

o Prof M Nambu, Japan, Plasma Maser Effects.

o Prof V Petviashvili, Russia, Vortexes in Space.

o Prof V Radhakrishnan, India, Pulsars--The Strangest Radiators in the Sky.

o Prof H O Rucker, Austria, Planetary Radio Emissions.

o Dr R Schlickeiser, Germany, The Theory of Cosmic Ray Transport and
  Acceleration and Astrophysical Applications.

o Dr K Stasiewicz, Sweden, Auroral Kilometric Radiation.

o Dr A V Stepanov, Ukraine, On the Penetration of Fast Particle Beams into
  Solar and Stellar Atmospheres.

o Dr B Thide, Sweden, Controlled Generation of Radio Emission in the Near-Earth
  Plasma by Wave Injection from the Ground.

o Prof V Trakhtengertz, Russia, Alfven Masers.

o Dr Yu M Yampolsky, Ukraine, Artificial Ionospheric Turbulence Investigations
  Using the Phased Array UTR-2.

o Dr V Zaytsev, Russia, Solar plasma.

o Prof V V Zheleznyakov, Russia, Cyclotron Resonance in Astrophysics.

General and topical lectures will be mixed with seminars and poster
sessions.  The lecture notes and reports of new results will be
published in "Radiophysics and Quantum Electronics".

Applications for attendance must be submitted before 15 March, 1993 to

Bo Thide
Swedish Institute of Space Physics
Uppsala Division
S-75591 Uppsala, Sweden
Fax: [+46] 18-403100
E-mail: [e-mail]

There will be an excursion to Vasil'sursk where the NIRFI radio
observatory ``Sura'' is located.  The cultural program of the school
includes sightseeing in interesting old Russian towns on the upper
Volga, art exhibitions, and other activities.

The total cost for full board an lodging on the ship for the school is
estimated at between US$300 and US$500, depending on type of cabin (first
class single, first class double, second class single, second class
double).





--
   ^   Bo Thide'----------------------------------------------Science Director
  |I|        Swedish Institute of Space Physics, S-755 91 Uppsala, Sweden
  |R|    Phone: [phone].  Fax: [phone].  IP: 130.238.30.23
 /|F|\          INTERNET: [e-mail]      UUCP: ...!mcvax!sunic!irfu!bt
 ~~U~~ ----------------------------------------------------------------sm5dfw-

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

Date: 22 Feb 1993 13:51:56 -0500
From: Pat <[e-mail]>
Subject: Mars Rescue Mission, what if!
Newsgroups: sci.space

Seriously, even at 200 million for an Energiya, I doubt that
anyone wants to spend that kind of money.  Most explorers know
that there is little chance of help on serious missions.
Lots of military operations are done on a no pick-ups basis.

Unless dozens of lifes are at stake, i can't see spending
100 million, 200 million on getting a monkey wrench shipped.

Lots of exploreers die, and they get their name stuck on a
street, an ocean or a mountain.

pat

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

Date: Mon, 22 Feb 1993 17:49:17 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: Nobody cares about Fred?
Newsgroups: sci.space

In <[e-mail]> [e-mail] (Allen W. Sherzer) writes:

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

>>actually the biggest paradox here is McDac.  AS Prime contractor on DC-X,Y.
>>THey seem to be doing a hell of a job on building a cheap,sturdy, reliable
>>LEO transfer vehicle. Oh, I forgot to mention flexible.

>>AS a major sub to Freedom, they are participating in a technological
>>boondoggle...

>I don't think it is a paradox. McDac is a large company and each
>project is for different managers with different expectations and styles.

>The lesson is to run projects like DC and not like Freedom.

Yes, but that is a lesson that was learned a long time ago at the
Lockheed Skunk Works, but which is almost impossible to follow when
dealing with the government (and bureaucratic NASA in particular).
The biggest difference between DC and Freedom is in who is on the
government side of the fence.

[I used to keep a copy of the Basic Operating Rules of the Lockheed
Skunk Works on the wall in my office, with several of the 'rules'
underlined.  It never seemed to catch on, though.  :-)]


--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

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

Date: Mon, 22 Feb 1993 18:01:59 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: Nobody cares about Fred?
Newsgroups: sci.space

In <[e-mail]> [e-mail] (Thomas Clarke) writes:

>In article <[e-mail]>
>[e-mail] writes:
>>  There is a great
>> deal of difference in just being up there to fly the flag and going up there
>> to do real work and real research.

>What is "real reasearch"?  I recall that during last summer's FRED budget
>battles, several scientific societies (after much soul searching, no
>doubt) recommended that FRED be cancelled since it did not provide the
>sort of capabilities they needed for their research.

Yes, and interestingly enough, many of those scientists are in fields
where they want unmanned probes and such, instead.  This pitting of
manned vs unmanned spaceflight is nothing new.  Space proponents need
to wake up and realize that *everyone's* ox gets gored when any major
space program is cut.

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

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

Date: 22 Feb 1993 13:43:24 -0500
From: Pat <[e-mail]>
Subject: Reliable Source says Freedom Dead, Freedom II to be developed
Newsgroups: sci.space

My feeling was something with a truss, in a higher more inclined orbit.
then modify the ETs  so they have hatches and "wet" structure.
Then just hang those onto the Truss, and bring equipment up in the shuttle
bay.  this was an original SKYLAB concept.

THe way I see it, is you get a quick volume, cheap  and NASA only has
to worry about the trusses and tanks and maintenance.  any experiments
can bring up their gear and the mission specialists can
install it.   If a submarine can be serviced entirely through
little hatches, i am sure a station could be too.

pat

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

Date: 22 Feb 93 09:11:30 GMT
From: Pat <[e-mail]>
Subject: Sabatier Reactors.
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (WELLS) writes:
{stuff deleted}

|>>type activities.  Refueling satellites is a very reasonable
|>>mission,  and it seems beyond the shuttles capacity.
|>>
|>>I would view this example as a reasoonable argument that the
|>>shuttle is a lousy workshop.
|
|
|Good suggestion...a few years late, but still a good suggestion. There
|have been several fluid transfer experiments flown on the shuttle. Very
|useful technology has resulted. One that comes to mind is the ORS,
|Orbital Refueling System. In this experiment, hydrazine
|Perhaps a little objective research is in order before we burn the books
|of knowledge that the shuttle program has written. Gosh, the very
|example cited here to condemn the shuttle as a "lousy workshop" is in
|reality a great example of why the shuttle program is a real bargain.
|Could the ORS experiment and demonstration have meant as much, and cost
|as little if performed another way? I think not.

But what is the point if those some technologies are never used.
I am glad ORS was done, and safer  and the MMU is refueled.
But look at NASA's own planning.  The Now dead SSF was going to
have no on-orbit refueling.  How is that useful?
The Centaur which could have benefitted from on-orbit refueling
never had a test program to achieve this mission.
What kind of bargain is it, when ORS is done, quite well from your
description, and then not placed into the technology bed for the
largest program in NASA history.

IT would be like Gemini testing Orbital rendevous and docking
and Apollo saying no docking is too risky and dangerous.
We'll use giant NOVA rockets instead.  at 100 billion dollars.

If you prove a technology and technique, use it.  if not, it's as
bad as never having done the test.

|The most expensive technology is forgotten or shelved technology. One
|can say that the shuttle is now expensive to run and made of outdated
|technology. Uhh,,,,yea, I guess thats right. In the same light I can
|scoff at my neighbor and his four year old antique home computer, while
|I hold out for more power and lower cost. But you and I should think
|carefully about how much benefit was obtained and is still coming from
|that old bucket while snipers sit on the sidelines with only inaccurate
|criticism in hand. Unlike the computer case though, as Gary C. pointed
|out, "The Shuttle is a marvelous workshop *solely* because it is the
|*only* heavy lift workshop *flying* regularly to various orbits..."..

Isn't this last statement the damnest criticism of NASA i can think of.
20 years after apollo,  and where are we?  8 flights/year ina workshop
whose owners are afraid of gassing your car.


|*Someone else* may buy those computers to drive up capabilities and
|drive down costs for you, but in the space biz, we're it. You wait, you
|lose.

  Kinda the way galileo waited?  or HST waited . or Skylab waited?
  lots of missions wait for shuttle.

|I'm sure you had a better idea when the shuttle was being developed;
|Heck, we all did, lots of 'em. But there is only one shuttle and it is
|the best that we could make it. I'm all for moving on to something
|better. You do it by building on what is past, taking advantage of what
|you have. The word "useless" has no place in the process.
|            NOTHING IS USELESS

  Nothing is useless.  My criticism is aimed at driving more
basic engineering testing using the shuttle  and towards an analysis
of the management culture that took us down this blind alley.
If we learn from the mistakes of the past we are better for it.


|Case in point, even your criticism is useful. It shows me that what a
|person doesn't know can hurt everybody. I urge critics to ask questions
|and become informed first and then shoot only if necessary. Chances are
|you don't have to shoot and everybody is the wiser for the questions
answered.

   My point was that no on-orbit cryo fueling has been tested or is
planned to be tested.  THis is a useful technology  and would make
lemonade from lemons.  I would suggest that you look into pushing
this sort of research from within.



>There is a lot of research out there being conducted on shoestring
>budgets that is enabling very much needed capabilities. I for one, would
>like to hear more that anyone can add to the REAL picture of space
>servicing. (Perhaps a new thread with this title.)
>

Well, i imagine one needs the management culture willing to
attempt it.

 No doubt money is short in important areas,  but it's also poorly
allocated in others.  NASA should return to their basic mission of
testing technologies and advancing research and not driving a bus
or running a business.  they aren't that good at it.

pat

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

Date: 22 Feb 1993 13:35:21 -0500
From: Pat <[e-mail]>
Subject: Sabatier Reactors.
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (fred j mccall 575-3539) writes:
|>>
|
|
|>If people are going to defend the shuttle as this marvelous
|>workshop,  then i suggest we see it do some real workshop
|>type activities.  Refueling satellites is a very reasonable
|>mission,  and it seems beyond the shuttles capacity.
|
|>I would view this example as a reasoonable argument that the
|>shuttle is a lousy workshop.
|
|Perhaps you should consider viewing it as a reasonable argument that
|there aren't any satellites to speak of that are equipped for 'in
|space' refueling, instead?  It has nothing to do with the Shuttle's
|suitability or non-suitability as a workshop.
|

Fred.
    Perhaps you should read all of the thread before posting.
No,  no satellittes are equipped for in-orbit refueling, because
NASA won't do it.   Why add a point of failure toa system if
you can't get gas.  The centaurs could have been equipped for
this sort of work,  but no-one at NASA has the guts to do this.
If you have a  workshop but the mechanic is afraid to open the
hood, you have a problem.   I am sure the galileo project office
would have been quite happy to have a direct trajectory to jupiter.

I am sure a lot of other missions would have been happy to use the centaur.
But NASA won't fly a fueled centaur, and won't fuel an empty
centaur in orbit.  So we end up with a problem.

If we had a centaur on galileo,  we probably could have then had
the shuttle crew, EVA to fix the stuck antenna.  instead, antenna
deploy had to be put off until after the venus encounter.

pat

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

Date: 22 Feb 93 18:29:43 GMT
From: Charles Chung <[e-mail]>
Subject: Wouldn't an earth to moon shuttle be better than fred?
Newsgroups: sci.space

In article <[e-mail]>
[e-mail] (Frank Crary) writes:
> The costs of a  station (as well as the delays and risks) far
> outweigh the extra efficiency made possible by a
> station.

Is this true for Fred in particular or for any space station?  Fred
is by no means optimised as a staging point.  Come to think of it, I
can't think of anything that Fred's optimised for.. except for maybe
porkbarreling.  <sigh>

-Chuck

---
*******************************************************************

    Chuck Chung                [phone] (O)
    Duke University Dept. of Physics    [phone] (H)
    Durham, N.C.      27706            [e-mail]

    "If pro is the opposite of con,
        then what is the opposite of progress?"

*******************************************************************

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

Date: Mon, 22 Feb 1993 15:46:11 GMT
From: "Bruce T. Harvey" <idsssd!bruce>
Subject: Wouldn't an earth to moon shuttle be better than fred?
Newsgroups: sci.space

in article <[e-mail]>, [e-mail] says:
> By the way Aerobraking is a wonderful way to match velocity between a
> returning lunar mission and the space station. Then after offloading you
> then could either refuel and resend to the moon, or via a tether de-orbit
> the returning lunar stage without using precious Space Station fuel or
> having to do fuel transfers.

If you have a purely non-atmospheric vehicle between station and moon,
wouldn't it be adding a GREAT deal of mass to this vehicle to enable it to
not only withstand the Aerobraking stresses but also (if I understand
correctly) the temperatures involved with atmospheric interaction?  Granted
that without aerobraking you'd need more fuel and some rather nifty velocity
changing but wouldn't that be preferable to the probable reduction in
carrying capacity TO the moon (supplies and such on which the moon base or
whatever would probably be dependant for a llooonnnggg time to come)?  Ok,
you could increase fuel spent going to, but then you're not only adding fuel
(as in the non-aerobraking) but also fuel and structural changes ... more
expensive in the long run as well as the short run.

Just a thought.
--
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End of Space Digest Volume 16 : Issue 217
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