Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V09_5/V9_597.TXT

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Subject: SPACE Digest V9 #597

SPACE Digest                                      Volume 9 : Issue 597

Today's Topics:
              Triton's retrograde orbit
              Re: Neil Armstrong
               Re: latest Quayle gaffe
             Quick and Dirty Won the Race
                 Buzz's jokes
         Re: Period of sidereal day on moon?y
              Re: Beyond Neptune
----------------------------------------------------------------------

Date: Fri, 28 Jul 89 18:02 EST
From: [e-mail]
Subject: Triton's retrograde orbit

Can Triton's orbit be explained via a collision involving Pluto?
(either directly or via some third body).

Thanks,
Bob

[e-mail] (internet)
krovetz@umass (bitnet)

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

Date: 27 Jul 89 09:29:58 GMT
From: mcvax!ukc!reading!cf-cm!cybaswan![e-mail]  (Steve Hosgood)
Subject: Re: Neil Armstrong

In article <[e-mail]> [e-mail] (Fred Sabernick) writes:
>There is a humorous but rather unflattering story about Neil Armstrong in
>Chuck Yeager's autobiography _Yeager_.

That's a good book! Actually, I seem to remember another story in the same
book about how Armstrong ran a jet into a hangar door because he killed
the engine(s) before he stopped rolling after a landing, not realising that the
engine(s) supplied the hydraulic pressure to the brakes!

To be fair, Yeager does commend Armstrong's piloting of Apollo 11.

This is also from memory..
Steve

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

Date: 24 Jul 89 23:16:00 GMT
From: ima!mirror!frog![e-mail]  (John Woods)
Subject: Re: latest Quayle gaffe

In article <[e-mail]>, [e-mail] (Jonathan Patrick Leech) writes:
> In article <[e-mail]> [e-mail] (Tom Neff) writes:
> >By the way this is only barely sci.space, but I assume folks have heard
> >about Danno's latest.
>     Perhaps this is a heretical thought, but it seems to me that
> Quayle is actually doing a *good job* as chairman of the NSC.  Now,
> maybe this is just because it's full of competent people; but even
> then, it shows he's listening to them.

Interestingly enough, it seems that he's doing a good job by _not_ listening
to the National Space Council.  Consider that his recent Mars Mission Three-
Part Plan (Space Station, Lunar trial base, Mars mission itself) was
supposedly cooked up by himself without giving the NSC members a chance to
pee in the plan (in particular, OMB was upset; their Mars mission plan reads
"Throw a paper airplane at Mars (used government stationery, 1 sheet; cost:
$1465, including folding and throwing labor, cost of cost estimate, cost of
cost-of-cost-estimate, and OMB administrative overhead, underhand, and
overarm).")

My fear is that he's just playing part of a "good cop/bad cop" team; the
"good cop" Quayle proposes a disturbingly sensible and long-range space
effort, the "bad cop" Bush says we can't afford it as long as there are
secondhomeless defense-contractor-CEOs, but the "administration" gets
favorable reviews because a sensible idea was spoken without immediate
retraction...
--
John Woods, Charles River Data Systems, Framingham MA, [phone]
...!decvax!frog!john, [e-mail], ...!mit-eddie!jfw, [e-mail]
    People...How you gonna FIGURE 'em?
    Don't bother, S.L.--Just stand back and enjoy the EVOLUTIONARY PROCESS...

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

Date: 27 Jul 89 07:58:31 GMT
From: uhccux!munnari.oz.au!otc!metro!basser![e-mail]  (Raymond Lister)
Subject: Quick and Dirty Won the Race

I thought readers might be interested in the following newspaper article.
Its from the Sydney Morning Herald, July 21st 1989 (Armstrong stepped on
the lunar surface on July 21, Australian time).

The story ran under the title "Quick and Dirty Won the Race". It is
reproduced here without permission.

---

While NASA celebrates the twentieth anniversary of man's first step on the
moon, all true space cadets should wear black armbands.  The Apollo project
was an expensive political gimmick which set back the exploration and
colonisation of space by more than a decade.

There are two ways to travel into space.  The first way is to ride in a
capsule on a ballistic rocket; it's a bit like flying in a cannon ball.  The
second is to use a rocket with wings.  And there are two ways to get back
down from space;  either in a capsule with a heat shield  (it's a bit like a
cannon ball with a parachute) or by gliding down like an aeroplane.

The cannon ball was the preferred means during the space race.  It was
the quick and dirty approach.  The necessary technology had already
been mastered by both the Americans and the Russians for transporting
their weapons of mass destruction.  However, a new vehicle is required
for every flight, so the cost is high.

In the long term, reusable winged craft are more economical for routine
access to space.  But during the sixties, long term economics stood little
chance against the short term political need to win the race to the moon.

The United States worked on rocket planes long before the space race.
In 1947, Chuck Yeager broke the sound barrier in a winged rocket called
the X-1. NASA is still developing X series research aircraft.  The
most famous is the X-15.  On July 19, 1963, the X-15 flew over 100
kilometres above sea level, making pilot Joseph Walker the first man to
travel into space on wings.

In 1981, journalists hailed the space shuttle Columbia as the first craft
to fly twice into space.  In fact, the X-15 achieved this in August 1963.
However, the X-15 was never designed to travel fast enough to reach orbit.
Its successor, the X-20, was intended to do that.

The US Air Force was so committed to rocket planes that it started work on
the X-20 in 1957, almost two years before the X-15's first flight. The X-20
was known as "Dyna-Soar", an abbreviation for "dynamic soaring". It was to be
boosted into orbit on a ballistic missile, but it was to glide back
Earth like an aeroplane.

But events had overtaken the rocket planes. The naive engineers of the
X-15 project could not understand the panic among the public when, on
October 1957, Russia launched Sputnik I. As millions listened to its
radio bleeps, they saw a future with orbiting nuclear weapons, ready to
fall and destroy the free world.

The public was shocked again in 1961 when Yuri Gagarin became the first
human cannon ball into orbit.  To the politicians, the press, and the public,
the Russians seemed to be far ahead.  In fact the Russians had pursued the
ballistic missile approach because winged space craft were far beyond their
capacity.  The United States was a long way ahead, but the technology was
too subtle.

When President Kennedy committed the United States to reaching the moon
before 1970, it was impossible for rocket planes to meet the challenge.  The
moon race killed off further development of winged space craft throughout the
60s.  In 1963, the X-20 project suffered death by a thousand cuts.  The
name "Dyna-Soar" had been prophetic.

The X-15 made its final flight in 1968.  It was still a useful research
vehicle, but NASA retired it for political reasons.  It was felt that
Congress would not fund the next generation hypersonic vehicle until the
X-15 was no more.  Congress didn't fund it anyway.  Today, the most
successful research aircraft ever flown hangs from the ceiling of the
Smithsonian Air and Space museum in Washington.

The US achieved the dubious honour of being first to the moon by
constructing the largest rocket that would ever fly.  The Saturn V stood 110
metres high on the launch pad.

All that remained by the end of the Apollo 11 mission was a command module
the size of a Volkswagon.

Even before Armstrong had taken his "small step", NASA knew it needed to
return to winged vehicles. NASA planned to build a space station and a fully
reusable vehicle was required to shuttle between it and the Kennedy Space
Center.

But Congress had other plans.  After Apollo 11, America  had more important
places to spend its money.  The war in Vietnam was expensive.  Later, the OPEC
oil prices left little slack in the national budget.

NASA reasoned that it would take several years to build the shuttle, and it
would face a battle every Budget.  If the shuttle's only rationale was to
ferry materials to a space station that would not be built until after the
shuttle was operational, how tempting it would be for Congress to cancel the
whole project.  An interim role for the shuttle seemed a prudent political
ploy.

NASA hit upon the idea of orbiting satellites from the shuttle. Since the
reusable shuttle would be cheaper to launch than the old expendable rockets,
NASA argued that there was no need for other rockets.  The shuttle would
become America's sole launch vehicle for both civilian and military satellites.

The assumption that the shuttle would be cheap to operate depended on
the idea of a completely reusable vehicle.  However, increasingly tight
development budgets forced NASA to look at a semi-reusable compromise.

The original shuttle design concept had two winged vehicles. The larger one
was called the booster, and was to carry the smaller orbiter on its back. The
booster would take off vertically, and fly to about 80km above sea level. The
orbiter would then fire its own engines and continue up to orbit.  Meanwhile,
the booster would fall back into the lower atmosphere, where it would start
turbofan engines and fly back to base, like a conventional aeroplane.

The anticipated development budget for this design was only half the
cost of the entire Apollo project, but the US government would not fund
it.  So NASA simplified the design, introducing semi-reusable rockets.

NASA had successfully reduced the cost of developing the shuttle to a price
Congress was willing to accept, but the cost of operating the shuttle went up.

NASA's ploy to use the shuttle to launch all American satellites meant
contending with the demands of the Pentagon.  The thought of an emergency
shuttle landing in a communist country, while carrying a military satellite,
was more than any general could bear.  The military insisted that the shuttle
be highly manoeuvrable, so that it could always land in a friendly country.
This requirement led to the large, heavy delta wings on the shuttle, and the
need for the heat resistant tiles.  Just as the politicians had hijacked
NASA in the sixties, the military hijacked the shuttle in the seventies.

When development problems arose during the moon race, money was available
to fix it.  However, Congress had capped NASA's shuttle budget. If more
money was needed to solve a problem, then NASA had to wait until it was
available in the following year's budget.  So, while the shuttle's
development budget stayed low within any one year, delay after delay
fashioned the cumulative budget into NASA's only skyrocket.

Today, America's shuttle fleet achieves nothing like the launch economies
that NASA had originally hoped for.

The space shuttle is no cheaper than expendable rockets for launching
satellites.  It may even be too expensive for servicing NASA's planned space
station.

NASA has to try to run a costly long term research project, when its budget
is subject to annual political review.  With the benefit of hindsight NASA
should never have attempted to build the compromise semi-reusable shuttle;
it should have stuck with expendable rockets.  This would have left enough
money for a modest but useful semi-permanent space station. In short, NASA
should have opted for the sort of space program the Russians run.

Believers in the one true winged path into space convinced President Reagan
to fund the X-30 National Aerospace Plane.  It will be completely reusable;
it won't require booster rockets; it will scoop up air to burn its hydrogen
slush fuel, resorting to rockets only for the last small push into space.

But America now faces its greatest budgetary problems in history. Congress
looks set to kill the X-30, like the X-20 twenty six years ago.  Until
winged travel into space becomes a reality, we will not return to the moon.

Raymond Lister
Basser Department of Computer Science
University of Sydney
NSW  2006
AUSTRALIA

[e-mail]@uunet.uu.net

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

Date:     Fri, 28 Jul 89 16:17 EST
From: <[e-mail]>
Subject:  Buzz's jokes

     A friend of mine saw the lunar landing on A&E and thought he heard Buzz
Aldrin say something as he was closing the outside hatch of the LM.  What
exactly did Buzz say?  Was it something like

     "and I'll try not to lock it." or "You got the keys?" ?

So, who taped the episode and can give me the answer.  E-mail me, by the time
I get the BITNET Digests, the leaves will be falling.  :-)

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
|  Arnold Gill                      |
|  Queen's University at Kingston   |
|  BITNET:  gill@qucdnast           |
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

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

Date: 28 Jul 89 22:39:51 GMT
From: attcan!utgpu!watmath!julian!uwovax![e-mail]  (Ken Hunt')
Subject: Re: Period of sidereal day on moon?y

In article <[e-mail]>, [e-mail] (Ted A. Campbell) writes:
> What is the period of a sidereal day on the moon?

    Hmmm. That's a toughie!

    I can tell you that it is going to be about the length of a lunar
    month, 29.5306 days. The moon has what is called a captured rotation
    Therefore it turns on its axis once every orbit. This is why we always
    see the same side. As for a sidereal day, there are going to be
    corrections for the obrit of the earth and such.

    I am not sure if that helped.
                -- Ken
--
!-----------------------------------------------------------------------!
! Ken Hunt,  Dept. of Astronomy, Dept. of Applied Math,                 !
!    University of Western Ontario, London, Ontario, Canada          !
! [e-mail]                                 [e-mail] !
! ----------------------------------------------------------------------!
! "In questions of science the authority of a thousand is not worth     !
!       the humble reasoning of a single individual." -Galileo Galilei- !
! ----------------------------------------------------------------------!
!      Signature subject to change without prior notification          !
!~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!

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

Date: 29 Jul 89 03:17:31 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utfyzx!sq![e-mail]  (Mark Brader)
Subject: Re: Beyond Neptune

> Ok, here's a far-fetched question..
> My understanding is that after the Voyager II Neptune fly-by, Voyager
> will head out of the solar system.  What possibilities are there for a
> slingshot around Neptune ... towards Pluto ... or back [inwards]?

None.  Slingshot maneuvers causing more than a slight alteration in the
vehicle's path are possible only when the escape speed of the planet --
actually the escape speed from the altitude of the closest permitted
approach is what matters -- is about as large as the vehicle's orbital
speed, or larger.  (Notice the many words in that sentence conveying the
idea that it is an approximation; still it will do for intuitive purposes.)

Now, the slingshot maneuvers that Voyager II has already undergone have
each added to its orbital speed.  It made it to Neptune in less than half
the time that a minimum-energy path would have involved.  So it's moving
much too fast now for Neptune to deflect it much at all.

In fact, this was also more or less true in the encounter with Uranus,
I think.  It was only the fact that the outer planets are roughly aligned
just now that made this "Grand Tour" trip possible at all.  And we're very
lucky that Voyager II made it, because it wasn't actually designed for the
trip, and we can all expect to be dead and buried before such an alignment
occurs again.


--
Mark Brader        We say, "But it wasn't designed to do that!";
Toronto            our managers say, "Our customers want this!";
utzoo!sq!msb        we say, "Small is beautiful!"; and they say,
[e-mail]        "Money is beautiful!"        -- Andrew Tannenbaum

This article is in the public domain.

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

End of SPACE Digest V9 #597
*******************