Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V15_3/V15NO374.ZIP/V15NO374

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Date: Wed,  4 Nov 92 05:00:05
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #374
To: Space Digest Readers
Precedence: bulk


Space Digest                Wed,  4 Nov 92       Volume 15 : Issue 374

Today's Topics:
            Automated space station construction (3 msgs)
                           low earth orbits
                        NASA Coverup (3 msgs)
                      pocket satellite receivers
               Scenario of comet hitting Earth (3 msgs)
      Surveyor landings (was Re: QUESTIONS: Apollo, Earth, Moon)
                Swift-Tuttle Comet a threat to earth?
                        the Happyface on Mars
                  The Meaning of Non-Voting (2 msgs)
                        TUNGUSKA/SWIFT-TUTTLE
                              Why Vote?
                            X-15  pictures

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

Date: 3 Nov 92 03:26:49 GMT
From: David Rowland <[e-mail]>
Subject: Automated space station construction
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:
>In article <[e-mail]> [e-mail] (I am a terminator.) writes:
>>Can robots be launched to build the space station? They can work overtime.
>
>People will depend heavily on robotic assistance for many tasks in space.
>However, an incident at the local Glad bag plant last night applies. A
>new robotic assembly line had just been started in the last month and
>all was going well with bags being produced and boxed. Then last night a
>temperature change caused a slight change in frictional coefficient, sound
>familiar? The robot started launching hot air balloons instead of neatly
>boxed bags. By the time the shift supervisor woke up, two trainees were
>chasing bag balloons all over the plant. They lost an hour's production
>and several thousand dollars worth of bags before the line was stopped
>and the bag blow pressure reduced slightly. The robots just kept mindlessly
>doing what they were told, even when it was disasterously wrong. On the
>old machines, the human operator would have just held the blow pedal down
>for slightly less time and bags would have continued to be produced.
>
>The moral of this story is that robotics is not yet adaptive enough to
>unexpected conditions to operate without waste and possible harm in less
>than critically supervised operations.
>
>Gary

But wouldn't the robots been discussed here be operated remotely by
ground based people.  This way, there is no need to program much AI
into the system.
--
| David Rowland       | The British are using New Zealanders.  They must |
| Datamark Intl Ltd   | really mean business !                           |
| Wellington          |      -  General Rommel During Northern African   |
| NEW ZEALAND         |         Campaign WWII.                           |

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

Date: 3 Nov 92 08:48:54 GMT
From: Carl Hage <[e-mail]>
Subject: Automated space station construction
Newsgroups: sci.space

[e-mail] (Henry Spencer) writes:
: In article <[e-mail]> [e-mail] (I am a terminator.) writes:
: >Can robots be launched to build the space station?
:
: Robotics technology is nowhere near building robots capable of such things.

Is this partly due to a focus on manned space missions? How much research
is done on developing space based robotic/remote-operated technology and
designing space hardware suited for robotics vs research on manned space
technology? Could this be somewhat of a self fulfilling prophesy in that
if we have a manned space capability, e.g. the shuttle, then it's easier
and more reliable to use it, therefore designs are made assuming manned
assembly, therefore robotics technology is nowhere near building robots
capable of such things and then we need manned space capability.

As mentioned in the other related posts, robotics techonology is being
used in the space station. I don't see robotics as an all-or-nothing
technology, and we really have a combination of manned and robotic
technology. The question is, what is the optimal balance between manned
and unmanned space exploration?

What's the point of automating assembly of a manned space station? Wouldn't
that be an unfair labor practice? A good part of the mission is to develop
manned space technology, e.g. assembly.

[e-mail] (Gary Coffman) writes:
: By the time the shift supervisor woke up, two trainees were
: chasing bag balloons all over the plant.

: The moral of this story is that robotics is not yet adaptive enough to
: unexpected conditions to operate without waste and possible harm in less
: than critically supervised operations.

Robotic technology != unattended operation.

 - - - -

Then again, wouldn't it be nice to have an astronaut with a crow bar on
Galileo. However, it would be cheaper and faster to build another probe
rather than add a capsule for a man.

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

Date: Tue, 3 Nov 92 14:23:38 EET
From: [e-mail] (F.Baube x554)
Subject: Automated space station construction

mike <[e-mail]> writes:
>
> [Robot] technology is too young to be trusted yet.

Much better to stick with O-rings ?

If the issue is trust [as it is this election day ?],
I thought that after Challenger, they stopped implying that
the shuttle was workaday "transportation", and resumed refer-
ring to it as officially "risky" for the people on board.

(This may be naive but ..) How difficult could it be to take a
collection of JPL and university robot tinkerings and put them
in a shuttle small package and put them thru their paces ??
The ones that look like they can work without babysitting
get subsequent rides on unmanned launchers.

Is every dry run for SSF construction going to involve hundred-
million-dollar gizmos with a MTBF of 0.2 shuttle missions ?

> Then again, some of NASA's funding comes
> from the romance of humans being there, not robots (IMHO).

Aha .. the truth will out.

fred :: [e-mail]

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

Date: Tue, 3 Nov 1992 10:37:04 GMT
From: Hartmut Frommert <[e-mail]>
Subject: low earth orbits
Newsgroups: sci.space

[e-mail] (Adrian Hassall Lewis) writes:

>The question:  Why is 28.5 degrees such a common orbit?

>I can understand the US launching to this inclination as the KSC is at 28.5N,
>but I've read that the ESA also launches to this orbital plane as well.  Isn't
>it most efficent for them to launch to a 1 degree orbit?

It is. But perhaps they count on shuttle rescue in case of upper stage
failure :-)

>Is it something to do
>with GTO? and if so, what?

I can't see what, since also that would be most efficient in the equatorial
plane.
--
 Hartmut Frommert                 <[e-mail]>
 Dept of Physics, Univ of Constance, P.O.Box 55 60, D-W-7750 Konstanz, Germany
                                           -- Eat whale killers, not whales --

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

Date: Tue, 3 Nov 1992 03:38:55 GMT
From: David Rowland <[e-mail]>
Subject: NASA Coverup
Newsgroups: sci.space,alt.conspiracy

In article <[e-mail]> [e-mail] writes:
<Invalid Stuff Deleted>

>   Watergate  and Iranscam are the tips of some very large icebergs. Some of
>   us have a difficult time figuring out why ,now that the "cold  war  "  is
>   supposedly  over, we need to have a National Security Agency in charge of
>   keeping an estimated 8 million secrets from the American public. What ,in
>   principle ,is to be gained by keeping the JFK Assasination  files  closed
>   until  well  into  the  next century, when all the likely participants in
>   this disgusting political takeover will have died of old age?  I  am  not
>   the  first  to  make  such  allegations  about  the moon landing charade,
>   therefore , suppression is attempted but fails.
>

I agree with the statement about the JFK files, however, know the
"cold war" seams to be over, this does not mean we will all live
"happy ever after".  When a super power becomes unstable, this causes
waves throughout the world which can have more need for the NSA then
previously.

I wonder wheither Iraq would have invaded Kuwait or if Yogoslavia
would have broken apart if the USSR had been more stable.
--
| David Rowland       | The British are using New Zealanders.  They must |
| Datamark Intl Ltd   | really mean business !                           |
| Wellington          |      -  General Rommel During Northern African   |
| NEW ZEALAND         |         Campaign WWII.                           |

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

Date: Tue, 3 Nov 1992 13:48:00 GMT
From: Marc W Mcconley <[e-mail]>
Subject: NASA Coverup
Newsgroups: sci.space,alt.conspiracy

In article <[e-mail]> [e-mail] (David Rowland) writes:
>In article <[e-mail]> [e-mail] writes:
><Invalid Stuff Deleted>
>
>>   What ,in
>>   principle ,is to be gained by keeping the JFK Assasination  files  closed
>>   until  well  into  the  next century, when all the likely participants in
>>   this disgusting political takeover will have died of old age?
>
>I agree with the statement about the JFK files, however, know the
>"cold war" seams to be over, this does not mean we will all live
>"happy ever after".

Sorry to participate in this awful flame war, but I just think it's funny.
This assumes, of course, that the JFK conspiracy was politically motivated,
when, clearly, it was masterminded by Elvis to get to Marilyn Monroe.

-Marc

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

Date: Tue, 3 Nov 1992 15:04:00 GMT
From: [e-mail]
Subject: NASA Coverup
Newsgroups: sci.space,alt.conspiracy

In article <[e-mail]>, [e-mail] writes...
>
>   snarfy charges,
>
>>>  NASA  physicists.....  YOU  ARE  withholding  the truth from the American
>>>  People...
>
>    In message-ID: <[e-mail]> (Henry Spencer) responds:
>
>>Oh, come now.  A conspiracy that large, held together for that long?  In
>>a government that couldn't suppress Watergate or Iranscam?  Come now.
>>This is laughable.
>
>   You  must  think  that  what  you  see on TV news is the entirety of what
>   really is going on in the world .  Now  some  might  find  such  naivete'
>   laughable, but I actually feel sorry for you.
>
>   Watergate  and Iranscam are the tips of some very large icebergs. Some of
>   us have a difficult time figuring out why ,now that the "cold  war  "  is
>   supposedly  over, we need to have a National Security Agency in charge of
>   keeping an estimated 8 million secrets from the American public. What ,in
>   principle ,is to be gained by keeping the JFK Assasination  files  closed
>   until  well  into  the  next century, when all the likely participants in
>   this disgusting political takeover will have died of old age?  I  am  not
>   the  first  to  make  such  allegations  about  the moon landing charade,
>   therefore , suppression is attempted but fails.
>
>>I also note that the conspiracy must extend to Japan, since their first
>>near-Moon navigation efforts, for Hiten, worked flawlessly.
>
>   The issue is not necessarily whether we landed on the moon , but  how  we
>   did it. The Japanese have this knack for doing anything we can do  ,  and
>   with better quality and precision.
>
>>>If you want  to  argue  about  the  merits  of  my  calculations...
>
>>What merits?  Just for starters, your calculations assume that the Earth
>>and Moon are motionless with respect to each other.
>
>   No  they  don't  .  Abell's lunar gravity figure of 1/6 assumes the earth
>   and moon rotate around a common barycenter. The neutral point  figure  is
>   a direct derivation of that result.
>
>   My  calculations  assume the neutral point to be motionless with respect
>   to the earth and moon . What do your calculations assume?
>
> snarfy
>
A very easy way to blow this one up is to look at the weight of the Apollo
LM and the thrust of the engine. The rocket equation says that there must be
at least a 1.141 thrust to weight ratio. Remember the LM only had one
Ascent stage. Henry can probably provide the numbers. Also remember that the
Astronauts suits and baggage were set up for 1/6 g and not .6 gee. If any of
you out there know Buzz Aldrin, there is no way he would keep something like
this covered up.

So there snarfy.

Dennis, University of Alabama in Huntsville

Also the pertubations of Lunar orbits by the Earth and Sun become significant
at altitudes above 800 km and dominate above 22,000. Look at Bill Sjogrens
papers on Lunar Gravity mapping and Browns Lunar Gravitational theory. Ask
the folks at JPL about Ranger, After Jim Burke got ahold of the program it
worked right.

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

Date: 3 Nov 92 08:48:56 GMT
From: Carl Hage <[e-mail]>
Subject: pocket satellite receivers
Newsgroups: sci.space

[e-mail] (Henry Spencer) writes:
: The noise being injected by DoD (the buzzphrase is selective availability)
: is currently of a relatively simple type that can indeed be removed by
: long-term averaging.

I have a few of questions. Suppose we end up with a president who places
a higher priority on commerce rather than restricting the military buildup
of countries like Iraq, and accurate navigation information is declassified.

  1. Can the "noise" be turned off, or do we need new satellites?
     (With DoD involved, this isn't a stupid question.)
  2. I thought selective availability mean't that noise was injected only
     during a military operation, e.g. the Gulf War. However, it wasn't
     enabled then due to a shortage of military units and many commercial
     receivers were used. Why do I read that commercial units still don't
     have the accuracy that military units have, i.e. how is full precision
     information transmitted?
  3. Would special or extra hardware be required to receive full precision
     information over existing receivers?
  4. Is differential GPS used just to overcome the selective availability
     noise, or are there other sources of error?
  5. What is the precision of commercial vs military GPS with/without
     SA enabled?

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

Date: Tue, 3 Nov 1992 08:19:25 GMT
From: Dave Tholen <[e-mail]>
Subject: Scenario of comet hitting Earth
Newsgroups: alt.sci.planetary,sci.astro,sci.space,talk.origins

Steve Linton writes:

> 2) controlling outgassing at perihelion where huge forces are at work. Does
> anyone know whether P/S-T meets Earth before or after perihelion?

In 2126, after perihelion.

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

Date: 3 Nov 92 09:23:55 GMT
From: John Black <[e-mail]>
Subject: Scenario of comet hitting Earth
Newsgroups: alt.sci.planetary,sci.astro,sci.space

What are the chances of the comet's orbit to be change significantly so that
the close approach or impact doesn't happen. More specifically, what is the
affect of outgassing or gravitaional interaction with a giant planet?


            John Black

PS no-one answered my question about what the "P/" means infront of comet names

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

Date: Tue, 3 Nov 1992 12:46:00 GMT
From: [e-mail]
Subject: Scenario of comet hitting Earth
Newsgroups: alt.sci.planetary,sci.astro,sci.space

In article <[e-mail]>, [e-mail] (John Black) writes:

[stuff deleted]

>             John Black
>
> PS no-one answered my question about what the "P/" means infront of comet names
==============================================================================
Just tried to mail an answer to you, but it bounced, so I'll hope you
see this.  The answer to your query about the "P/" prior to the name
of a comet has been answered in the sci.astro news group.  It means
that the comet is periodic.

Regards

Scott Miller, Program Coordinator
Rauch Memorial Planetarium
University of Louisville
[e-mail]

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

Date: 3 Nov 92 15:06:00 GMT
From: [e-mail]
Subject: Surveyor landings (was Re: QUESTIONS: Apollo, Earth, Moon)
Newsgroups: sci.astro,sci.space

In article <1992Nov2.175554.26242@kbsw1>, [e-mail] (Chris Kostanick 806 1044) writes...
>In article <[e-mail]> [e-mail] writes:
>>further  reduce the descent velocity.  At 4.3 km above the surface, the
>>three thrusters were shut off, and the spacecraft simply dropped the
>>remainder of the way down, landing at a velocity of 11 km/hour.
>>
>
>
>If I understand you correctly, this means that I could drop over
>a mile on the moon and walk away from the landing. (I can walk into
>a wall at better than 6 miles an hour and not get hurt.) This
>opens up the possibility for some _outrageous_ trampoline action
>on the moon. Drop a mile, hit the trampoline and bounce almost a
>mile back up. This sounds like big action fun. We need to go back
>to the moon NOW.
>
>
>--
>Chris Kostanick
>"Outside of a dog, a book is a man's best friend. Inside of a dog
>it's too dark to read." - Groucho Marx

Oh well Ron shoulda dropped the "k" in "km" then it works just fine. Hey
its only decimal points!!

Kinda like Clintons tax and spend plans.

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

Date: 3 Nov 92 13:58:47 GMT
From: Gerald Cecil <[e-mail]>
Subject: Swift-Tuttle Comet a threat to earth?
Newsgroups: sci.space

The need to emplace a transponder on Swift-Tuttle should finally
provide the motivation/lead time to build a viable, deep space ion
drive!  This is just the sort of thing you could give to the weapons
establishment to tinker with.  They may have other things to do:

Today's NY Times quotes Dr. J. Solem, physicist at Los Alamos,
who suggests (no details) that 10-100 Megatons would be needed to impulsively
deflect Swift-Tuttle out just beyond Saturn's orbit in 2122 (T -4 yrs).
This is a realistic detection limit assuming no large-aperture space or
lunar telescopes.  Another opportunity would come ~15 days before closest
approach, when he claims that you'd need 1-10 Gigatons.  The largest
nuclear detonation is estimated to have been 60 Megatons.
---
Gerald Cecil [e-mail]  919-962-7169
Physics & Astronomy, U of North Carolina, Chapel Hill, NC 27599-3255 USA

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

Date: Tue, 3 Nov 1992 14:35:47 GMT
From: Ed McCreary <[e-mail]>
Subject: the Happyface on Mars
Newsgroups: sci.astro,sci.space

In article <[e-mail]> Kevin William Ryan <[e-mail]> writes:
>>Well, I'm happy, I received my Mars CDROMs in just the other
>>day.  I like to find the images that show the "Happyface" on
>>mars and the Kermit the Frog.  If anyone has either the Lat/Long.
>>or the image id of the pics, I'd appreciate hearing from you.
>
>    The picture id's of the mars face images are 35a72 and 70a13. They
>look best after median filtering and contrast enhancement. Enjoy...
>
>    Sorry, I don't know what the id of the Kermit pic is.
>

thanks, but I've had those for a while and I don't think they're on
the CDROMs.  What I'm looking for is one image which looks like
a happy face or smiley face.  It's a circle with two eyes and a mouth.
The other is what appears to be a series of ancient river beds in
the shape of Kermit the Frog.


--
In the midst of the word he was trying to say,|[e-mail]
     In the midst of his laughter and glee,   |Me, speak for Compaq?
He had softly and suddenly vanished away---   |Yeah, right.
     For the Snark *was* a Boojum, you see.   |#include <stddisclaimer.h>

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

Date: Tue, 3 Nov 92 15:25:09 EET
From: [e-mail] (F.Baube x554)
Subject: The Meaning of Non-Voting

somebody wrote:

> >Clearly, an individual's vote doesn't matter at all as evidenced
> >by the way the election turns out whether they vote or not.
> >Voting is a symbolic, not a functional, act.

There was a discussion of this some time ago on anarchy-list.
The conclusion (IMHO only) was that not-voting has symbolic
meaning ONLY if it there is a clearly organized voting boycott,
as has been happening in Eastern Europe from time to time.

If you don't vote today, the State Managers and their media lackies
can and will mark you down in the Too Content to Bother to Vote column.

If you don't like the Repocrats or Demopublicans, vote for a 3rd party.

fred :: [e-mail]

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

Date: Tue, 3 Nov 92 10:43:43 est
From: [e-mail]
Subject: The Meaning of Non-Voting

Do you have a right to vote in Finland? I certainly can't vote here.
Even if I wanted to. It's unusual for me to care, but I actually hope
Clinton wins. This country could really need a public health
insurance... And he's for a maglev train system criss-crossing
America, too.

How are things in Suomi and your neck of the woods these days?

-Jan.

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

Date: Tue, 3 Nov 1992 13:42:40 GMT
From: [e-mail]
Subject: TUNGUSKA/SWIFT-TUTTLE
Newsgroups: sci.astro,sci.space

The following are comments from Duncan Steel on some recent postings
on sci.astro and sci.space. Please address responses to his email
address. I am posting this for him as he does not have direct access
to UseNet.
Peter Brown
=======================================================================

SOME COMMENTS ON RECENT DISPARATE POSTINGS W.R.T. TUNGUSKA AND P/SWIFT-TUTTLE


(1) Tunguska object being stoney: The work referred to is by Chris Chyba
   (now at NASA-Goddard SFC), Paul Thomas (U. Wisconsin-Eau Claire) and
   Kevin Zahnle (NASA-Ames RC).  They have a paper prepared which shows that
   the Tunguska event is consistent with the entry of a stoney asteroidal
   object about 50 m in size (i.e. there is NO NEED for a fluffy underdense
   object like a "comet" fragment - as if we know anyway what a comet is
   like; hell we don't even know P/Halley's density to within a factor of 3).
   I imagine that they would have given a paper on this at the DPS in Munich.

(2) Frequency of Tunguska-type impacts.  The thing which MAY be wrong with
   most of the discussions is that it is generally assumed that such objects
   hit Earth randomly in time.  This is daft in that we know that a good
   fraction - perhaps even the majority - of the mass influx of smaller
   meteoroids hit the Earth in showers (meteor showers).  These occur as
   the Earth passes through the the meteoroid stream produced by an
   asteroid/comet.  They recur each year since the smaller particles produced
   by the cometary decay are spread around its orbit by ejection speeds from
   the comet nucleus, radiative forces etc.  However, there is a concenration
   close to the cometary nucleus (cf. cyclic meteor storms such as Leonids,
   Draconids, Perseids in 1992 - and in 1993/94?).  The large particles are
   also grouped close to the nucleus since ejection velocities are small,
   and radiative forces insignificant.  What if a giant comet fragments,
   leaving some km-sized lumps but many more smaller ones (50-100m)? These
   will be mostly in a clump.  At such time as the orbital precession/
   evolution gives a node at 1 AU, a shower of large lumps may occur: but
   not every year, only when the clump is at the right (wrong?) point in
   the orbit, like the Leonids recurring every 33 yr (the orbital period
   of the parent comet).  Anyhow, the above would lead to the following
   occurring: a few random incoming Tunguska-type objects every so often
   (every few centuries), but every millenium or so (time depending upon
   exact orbit because of precession rate) there will be a phase of a
   century or so in which every few years/few decades there is a large number
   of Tunguska-type events spread over a week or so, and this dominates the
   long-term (sporadic) influx.  This I call "Coherent Catastrophism", and
   catastrophic it would be.  Indeed, I believe, it "has been", judging
   from the historical record, since this is what is going on at the moment,
   with us now (late 20th Century) being in a hiatus between mass influxes.
   I would refer one and all again to V.Clube and B.Napier, "The Cosmic
   Winter", Blackwells, Oxford & NY, 1990, for the historical stuff.  For
   the nitty-gritty w.r.t. the meteoroids (small ones in showers observed
   now) see Steel, Asher & Clube, Mon Not Roy Astron Soc, 251, 632, 1991.
   Since then we have looked at the asteroids which we believe to be members
   of the complex (see Steel, The Observatory, 112, 120, June 1992) and
   shown that at the >95% confidence level there are 8/9 objects in the
   inventory of known Apollo asteroids which are members of this complex
   (Asher, Clube & Steel, presented at Meteoroids and their parent bodies,
   Slovakia, July 1992 and Mon Not Roy Astron Soc, submitted).  This would
   imply that there are many more smaller objects (50-100m?) which have
   orbits which do not have a node at 1 AU at present, but will precess
   so as to do so before too long!  Outliers in that respect include the
   Tunguska object itself, the 1975 lunar impactors (also detected on
   Earth as ionospheric disturbances: Kaufmann et al, Science in 1989 I
   think), and 1991 BA (that 5-10m near-miss asteroid/meteoroid).  As I
   have said before, I do not know when the world will end but I would
   bet that it'll be in the last week of June one year.  You all might
   like to note that the above ideas on Coherent Catastrophism were
   totally excluded from the NASA report on how to search for Earth-crossing
   objects (Report of the Near-Earth-Object Detection Workshop, ed.
   D. Morrison) despite my best efforts as one on the committee members
   to have it included.

(3)  There has been a lot of bull written in these columns about
   P/Swift-Tuttle and whether it will hit the Earth and what the
   consequences might be.  Here is what led to the news stories.
   In IAU Circ 5636 dated October 15th Brian Marsden pointed out that
   with present orbital solutions and their acknowldeged uncertainties
   an impact on 2126 August 14th is/was possible.  Whenever something
   topical comes up I do some radio interviews with Australian Broadcasting
   Corp stations here, to keep the Australian public abreast of what is
   going on: good for astronomy, good for space, good for science all
   round.  I also informed a few newspapers here.  To that extent the
   Australian public knew all about this story a week or more ahead of
   the populace elsewhere, and with that in mind I would encourage others
   spread all over to do something to keep the public informed about what
   is happening; hell, they (mostly) pay for our salaries, equipment,
   education.  Getting back to Oz, I did my first radio interviews on
   Oct 16th (Darwin & Adelaide), then every other capital city on Oct
   19-21.  The first story in print was, I believe, in The Australian
   newspaper dated Oct 20.  That weekend there was a 3-day conference
   (National Space Development Conference) in Sydney and I gave a talk
   on our program here searching for near-Earth asteroids, NASA plans,
   international plans, SDI involvement, etc.  The case of P/Swift-Tuttle
   was/is an excellent example: a possible impactor, > 100 yrs notice,
   requires observations over the next 5/6 yr from the southern hemisphere
   for better knowledge of whether an impact is likely. (Despite that, it
   turns out that we have no funding as from December so that our program
   will be closed down, resulting in no southern hemisphere searches; I
   would also point out that the US searches have depended upon us for
   follow-up of objects moving south but we will be unable to do this from
   now on.  This is due to the idiocy of the Australian government; we
   have had great support from our north American co-workers in trying to get
   funding here).  Anyhow, back to the talk in Sydney.  The local Reuters
   correspondent was there and after discussions with me on the topic he
   put out a wire story which led to the furore.  Indeed he says that no
   story that he has previously filed has got as wide a response.  So far
   as I know the story he put out was accurate (saying that the CHANCE of
   an impact existed) except that he got the year wrong: 2116 instead of
   2126.  You would not believe where the story was carried: for example
   front page of THE TIMES (London) with an editorial, and a reply by
   Marsden (Oct 30), page 3 of THE SUN (London) with a semi-naked lady,
   front page of a paper in Fort McMurray (Canada) sharing top spot with a
   story about a moose.  I fielded phone calls from all over the world:
   most of them based upon errors and misconceptions. "Such is life" (the
   last words of Australian anti-hero Ned Kelly).

(4) Impact velocity by P/Swift-Tuttle: this is known accurately.  If the
   comet does not hit this next time but it does at some time in the
   future then whenever that occurs the speed would be between 60 and 61
   km/sec (see my paper MNRAS, 227, 501, 1987) unless its orbit (a,e,i)
   changes appreciably.  The 60-61 km/sec ariation is due to
   the eccentricity of the Earth's orbit and hence terrestrial speed.
   For 2126 August 14 the speed can be found exactly, but I haven't done
   it; it's not important since the mass is so poorly estimated.

(5) Using an assumed sphere of diameter 5 km, density 1 gm/cm3, I get
   an energy of above 20 million Megatonnes, or around 1 billion times
   Hiroshima.



Duncan Steel,
Anglo-Australian Observatory,
Coonabarabran, NSW 2357.

"[e-mail]"

=====================================================================


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

Date: 3 Nov 92 15:15:26 GMT
From: Steve Adams <[e-mail]>
Subject: Why Vote?
Newsgroups: talk.abortion,soc.motss,sci.space

[e-mail] (Ray Fischer) writes:

>[e-mail] (David Knapp) writes ...
>>Clearly, an individual's vote doesn't matter at all as evidenced by the
>>way the election turns out whether they vote or not. Voting is a symbolic,
>>not a functional, act.
>
>If you're a Republican: Yes, you are correct.  Don't bother.
>If you're a Democrat:   Bullshit.  Get your lazy ass in there and VOTE.
                                               ^
                                               |

A Freudian slip, Ray? ;-)----------------------|

>:-)
:-) :-)

All of you, Republicans, Democrats, Independants, Libertarians, etc get off
your butts and vote!

 -Steve
--
  The opinions expressed above are those of the author and not SPSS, Inc.
                         -------------------
   [e-mail]                                  Phone: [phone]
   Steve Adams        "Space-age cybernomad"       Fax:   [phone]

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

Date: 3 Nov 1992 15:03:04 GMT
From: Claudio Egalon <[e-mail]>
Subject: X-15  pictures
Newsgroups: sci.space

I would like to know where I could get hold of X-15 pictures for
possible publication. I am also interested, specifically, in a picture of
one of the first flights of the X-15 that was flown by Scott Crossfield in
which the (space)craft crashed and was broken in its very middle
(Crossfield survived). I have never seen a picture of the X-15 after this
accident and I am curious how it looked like.

[e-mail]

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End of Space Digest Volume 15 : Issue 374
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