Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v09_6/v9_610.txt

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Subject: SPACE Digest V9 #610

SPACE Digest                                      Volume 9 : Issue 610

Today's Topics:
            Re: Martian enigmas...
             Re: Henry's (not Weinhards)
          Re: space news from June 26 AW&ST
            Re: neptune encounter
              Re: Beyond Neptune
          Re: Does This Proposal Make Sense
           exploding Saturns, lack thereof
         Re: The Soviet PHOBOS 2 Mars probe.
          Re: Space telescope - why only 1200 hours?
          Re: powering down old experiments
          Re: Space telescope - why only 1200 hours?
             Re: Moon instruments
           Re: Catch-A-Planet (More than a Summary)
              Galileo followons
----------------------------------------------------------------------

Date: 4 Aug 89 04:19:01 GMT
From: jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Martian enigmas...

In article <[e-mail]> [e-mail] writes:
>I'm new to this list.  My question is...Has there been any discussion
>of the Martian "enigmas" photographed by Viking and Mariner?

Hoagland's "enigmas" come up regularly here.  The general (although not
universal) opinion is that he's building a whole lot of speculation on
awfully slender evidence.  You can find similar shapes in landforms on
Earth if you look for a while.  (Surely Italy's resemblance to a boot
is too close to be accidental? :-))
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 4 Aug 89 03:15:02 GMT
From: jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Henry's (not Weinhards)

Eugene Miya wrote:
>>                So Henry has pushed most people's internal
>>button's too far and lost credibility.

Every now and then I wonder if I'm being too hard on NASA, criticizing it
more than it deserves and thus making a fool of myself in front of the
people inside who really know what's going on.

And then I get a letter from someone inside NASA or a NASA contractor,
or somebody who's recently escaped :-), saying roughly "you have no idea
how bad it really is..." and going on with enough detail to be convincing.

So I keep at it.
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 4 Aug 89 03:19:40 GMT
From: jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: space news from June 26 AW&ST

In article <[e-mail]> [e-mail] (Bruno Poterie) writes:
>>   Ariane 5 development program will probably slip several months...
>
>Which firm was building those mixers? I bet that it is a private company.
>If confirmed, this is one more reason to doubt about the validity of the "private"
>approach. If Arianespace had had a contract with the NASA or with another
>government or official agency, it would have been respected...

Ha ha.  Ho ho.  Hee hee.  Remember Ulysses, nee *International* Solar Polar
Mission?  The US government can and does renege on both promises and out-
and-out contracts.  Ask most anybody who had a commercial launch booked on
the Shuttle at the beginning of 1986.  Those people didn't even get their
deposits back, as I recall.  Some of them seriously thought about suing the
US government.

I don't recall the details, but the mixers were undoubtedly being built by
private industry.  However, the diversion was the government's idea.
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 4 Aug 89 03:52:30 GMT
From: jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: neptune encounter

In article <[e-mail]> [e-mail] (J. Michael Butters) writes:
>Way back in December, 1970, National Geographic had an article in their
>monthly magazine entitled "Voyage to the Planets" which discussed the
>missions of the Voyager spacecrafts and their planned trajectories
>to ALL the planets of the solar system.  One of the crafts was to pass
>well under the planet Saturn which would send it at an angle up to the
>planet Pluto.  I never did learn why this plan was rejected and Pluto
>left out of the mission.

The original "Grand Tour" project planned to do it.  It may have been
pencilled in in early Voyager planning.  But there were only two Voyagers
actually funded for launch, and their primary targets were Jupiter and
Saturn, with the Voyager 2 Uranus/Neptune mission finally okayed only in
flight, after it was clear that both Voyagers were working well and the
the Jupiter/Saturn mission was unlikely to suffer.  (The early name for
Voyager was "Mariner Jupiter/Saturn".)  There was a proposal to launch
the third Voyager -- the ground spare -- onto the Jupiter/Saturn/Pluto
trajectory.  Never happened; Voyager 3 is in the Smithsonian, along with
Viking 3.
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 4 Aug 89 04:30:07 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Beyond Neptune

In article <[e-mail]> [e-mail] (Charles Daffinger) writes:
>Alternatively, if Voyager II heads out of the solar system, how much
>longer will we be able to maintain radio contact?  Will the probe be
>sending back information at that time, or will it be simply shut off
>and left to drift?

There was a paper in JBIS a few years ago, by some of the Voyager people
at JPL, addressing this.  There are several limits involved:  attitude-
control fuel, communications bandwidth, and electrical power.  It turns
out that the limit is electrical power.  The isotopes in Voyager's power
packs are decaying steadily, and the power output is dropping accordingly.
Sometime around 2010, as I recall, there is no longer enough power to
run the "housekeeping" systems plus the four experiments that yield useful
data in deep space, and it will be necessary to start shutting things down.
A few years later, there isn't enough to run even the housekeeping systems
alone, and that's it.  Barring problems, control fuel will easily last
that long, and communications would not be a problem until rather later.
Whether the electronics will keep going that long is somewhat of an
open question -- both Voyagers have had non-fatal electronic failures
already -- but there is no definite reason to think they won't.

Whether the Voyagers will be shut down before then to save money on
control and monitoring efforts here on Earth is a separate question.
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 4 Aug 89 05:07:06 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Does This Proposal Make Sense

In article <[e-mail]> [e-mail] (Karl Redell ) writes:
>...Only a government can tax millions of people
>to generate the billions of dollars required.  Designing and building
>a satellite, which can be done in any university physics lab, should
>not be confused with building a launch vehicle.  If you have seen one
>close up, you will realise that a launch vehicle can not be turned
>out by your machinist working after hours.

Gee, that would surprise Gary Hudson or the late George Koopman.  Or
Wernher von Braun, for that matter, if he were still around to be asked.
(Remember that the VfR was flying liquid-fuel rockets fairly reliably to
altitudes of 1-2 km in 1932, five years after it was founded by nine
men in a restaurant, without a penny of government money and with only
inconsequential assistance from outside, with 1930 technology.  Things
might have gotten interesting if Germany had kept its head above water
politically for a few more years.)

Yes, I have seen launch vehicles close up.  I have also seen the equipment
that von Braun used to launch Explorer 1 close up; I could easily build
something better in my own little electronics shop, with thirty years of
better technology to build on.

It may not have come to your attention, but the sexiest new launcher, due
to fly most any time now, is a purely private venture that is costing OSC
and Hercules a total of about $70M.  (They have some government customers,
and said customers are supplying the launch aircraft for carrying Pegasus
up to altitude for their launches, but Pegasus itself is all-private.)
Now, $70M isn't exactly an after-hours budget, but Pegasus is a fairly
conservative (in most ways...) project being done in fairly conservative
ways by traditional aerospace contractors.

>... It is just not possible, unless you
>have worked in the space industry, to realise how much time, effort,
>coordination, raw materials, testing, etc. go into the manufacture
>of something even as relatively simple as an ICBM.

What has that to do with launchers?  Confusing MilSpec ICBMs with
civilian space launchers easily adds an order of magnitude to the budget;
some would say two or three.  Launchers should be *simpler* than ICBMs,
not more complex.
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 4 Aug 89 05:18:36 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: exploding Saturns, lack thereof

In article <[e-mail]> [e-mail] (Brian P. Dickson) writes:
>In the motion picture _Koyaniskaaski_ (sp?), there is a five minute
>sequence at the end, where what appears to be a Saturn V is launched,
>and in one continuous shot, explodes, with the camera following one
>of the enormous engines for a very long time. Does anyone (Henry?) know
>which vehicle this was, and why it detonated? ...

It wasn't and it didn't.  No Saturn Vs exploded.  In fact, my memory and
a quick look at the references concur:  no Saturns of any flavor (I, IB,
or V) exploded, although some flights did have significant problems.

A possible confusing factor is that Saturn V staging was *very*
spectacular and the first staging event happened early enough that it
was readily visible from the ground.  It looked heart-stopping when you
saw it live for the first time, with a huge sheet of flame erupting outward
sideways from the rocket, followed by the first stage falling behind
and the relatively inconspicuous second stage (oxyhydrogen engines don't
make much of a visible flame) continuing upward.
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 4 Aug 89 02:54:52 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: The Soviet PHOBOS 2 Mars probe.

In article <[e-mail]> [e-mail] (CUP/ASG, MLO5-2/G1 6A, 223-3283) writes:
>    ... a technical error with the craft itself is believed to have
>    been the problem...

In fairness, it should be pointed out that (a) Phobos 2 had done point-
shoot-repoint-transmit maneuvers before, successfully, (b) there are
indications that it may have been *spinning* after whatever it was
happened, and (c) unlike Phobos 1, nobody has been able to point to
a specific error to explain the Phobos 2 loss.  The suggestion of a
collision with debris in Phobos's orbit, or P2's own maneuvering stage,
may seem a bit convenient for the engineers, but it does explain these
difficulties.  We may never know for sure.
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 4 Aug 89 02:59:10 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Space telescope - why only 1200 hours?

In article <[e-mail]> [e-mail] (Tom Neff) writes:
>HST is a very heavy payload designed to be serviced by the Shuttle, which
>cannot visit orbits higher than about 300nm under any circumstances.  Hence
>it lives in LEO.  Welcome to the joys of "manned presence in space."

Name an unmanned system, except Energia, that could do better for a payload
that big.
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 4 Aug 89 03:36:09 GMT
From: jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: powering down old experiments

In article <[e-mail]> [e-mail] (Lee Mellinger) writes:
>None of the Mariner or Viking spacecraft were turned off to save
>money...

However, there was at one point a serious risk that the surviving Viking
lander (which was number 1, not 2) would be turned off to save money.
Fortunately it didn't happen, partly thanks to the Viking Fund's efforts
at private fundraising (which were significant more for showing public
support than for the actual cash raised, although it was noticeable).
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 4 Aug 89 02:58:07 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Space telescope - why only 1200 hours?

In article <[e-mail]> [e-mail] (Brian Yamauchi) writes:
>Why does it really need to be LEO?  Why not put it in a higher orbit?

Because no launcher on Earth, except Energia, could get it any higher.
The HST is *heavy*.

There is also a strong desire to put it somewhere where it can be serviced,
so that new instruments can be installed on it eventually.  Development of
second-generation instruments is already well underway.
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 4 Aug 89 04:46:32 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Moon instruments

In article <[e-mail]> [e-mail] (David Palmer) writes:
>... and the 'passive seismometer'.
>What do they mean by passive?  All the passive techniques I can think of
>for seismometry are relatively insensitive.  Does passive just mean
>'solar powered' or something like that?

"Passive" seismometry is just listening, as opposed to making something
go bang and listening for the echos from down below.  All the Apollo
seismometers were primary passive, but the later ones got active on
occasion :-) when Saturn V third stages and leftover LM ascent stages
were deliberately crashed on the Moon.  They also gave us a lot of data
on the abundance, or rather lack thereof, of large meteorites -- the
Moon is seismically a rather quiet place, and the Apollo equipment was
eventually considered capable of hearing a basketball-sized meteorite
hitting anywhere on the Moon.
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 4 Aug 89 04:40:51 GMT
From: jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Catch-A-Planet (More than a Summary)

In article <[e-mail]> [e-mail] writes:
>3. Do we ALREADY have the techniques to detect other planets?
>Anita Cochran (sp?) said we are very close to it, at least
>from spectroscopy. Can anyone provide more updates?

The ultra-precise Doppler-shift technique invented a few years ago by the
British Columbia astronomers [apologies; I don't remember exact names and
locations] can fairly easily measure the motions of stars caused by large
planets.  It measures velocity [!] along the Earth-star axis rather than
position perpendicular to that axis, and is precise enough to get results
that most everyone believes (unlike perpendicular-position measurements,
which push things very hard and have many subtle sources of error).  The
biggest problem so far is that such planets will have orbital periods at
least a few years long, and one would like to observe several orbits to
be sure, and there hasn't been that much time yet!  There are a *lot* of
tentatively-positive results already.

Also, don't forget that at least one of the stellar dust disks inferred
from IRAS data has been "seen" optically using CCD detectors and good image-
processing methods.  If you're willing to go with a decidedly broad
definition of "planet", that settles it.
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 4 Aug 89 04:15:42 GMT
From: jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Galileo followons

In article <[e-mail]> [e-mail] (Jonathan Patrick Leech) writes:
>>... For that matter, Galileo has been
>>almost-ready-to-fly for a decade now -- where is *its* followup?  (Answer:
>>there isn't one.)
>
>    How can you design a followup to a mission that hasn't flown yet?
>It would be silly to build something else and launch it before Galileo
>tells us the next questions to ask.

Such silliness went on quite extensively, and quite successfully, in the
Apollo era.  There are *lots* of questions about the Jovian system that
Galileo isn't going to even address, never mind answer.  There are
people who would sacrifice semi-essential parts of their anatomy :-) to
see a modified Viking lander set down on Io or Europa.  Given a choice
of launching such a thing to accompany Galileo, with imperfect knowledge
of the environment it will find and the possibility of wasted effort,
or waiting until Galileo results are complete nearly a decade from now,
guess which they'd choose?
--
1961-1969: 8 years of Apollo.  |     Henry Spencer at U of Toronto Zoology
1969-1989: 20 years of nothing.| uunet!attcan!utzoo!henry [e-mail]

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

End of SPACE Digest V9 #610
*******************