Article-I.D.: <1792@aecom.UUCP>
Date: Thu, 11-Jul-85 23:55:41 EDT
Article-I.D.: aecom.1792
Posted: Thu Jul 11 23:55:41 1985
Date-Received: Sat, 13-Jul-85 02:30:28 EDT
Distribution: na
Organization: Albert Einstein Coll. of Med., NY
Lines: 27

Condensed fr. NY Daily News, by Edward Edelson, Science Editor.

	While the publicity builds for Halley's comet, Voyager II is plodding
steadily at 40,000 mph towards another planetary encounter.
	When it reaches it's next target, Uranus, Voyager will be more than
eight years from Earth and more than four years past its last target, Saturn.
	Comparatively little is known of Uranus. What is known that Uranus
is 64X the volume of the Earth, has five moons and a tedious set of dark
rings, discovered only in 1969.
	
	Most of the work will be done in a few hours when Voyager makes
its closest approach at 1 pm next January 24. (Mark your calendar -:))
The data will actually reach Earth 2 hrs 43 min later, from the satellites
25 watt radio transmitter (Only 25 watts - pretty amazing reception, if you
ask me!)
	After that it will reach Neptune on Aug 24, 1989, and then be propelled
downward out of the solar system.  (It's companion, Voyager I was propelled
upward out of solar system immediately after encountering Saturn)
	Signals should come from the satelites as long as their power holds
out, which could be as late as 2005 or 2010. (They run on Nuclear decay, if
I am not mistaken.)


-- 
				Craig Werner
				!philabs!aecom!werner
		"The world is just a straight man for you sometimes"

Article-I.D.: escher.38
Posted: Wed Jul 17 22:32:56 1985
Date-Received: Fri, 19-Jul-85 02:04:28 EDT
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Organization: NASA/JPL, Pasadena, CA
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	A while ago, there were some questions about
Voyager 2s condition and what its chances are of hitting or
being thrown seriously off course by gravity from Uranus's
moons.  I talked it over with one of my friends in
celestial navigation and got this:

	Noone is quite sure of the mechanical condition of
the machine, but they believe it is quite fine.  There is
more worry about radiation damage to the electronics.  It
turns out that most of the electronics slowly recovers from
radiation damage if it is powered down, but there is the
tradeoff that something powered down might never come back.
Also most of the more critical circuitry in attitude
control, etc can't realistically be turned off.  It's to
risky, so they eat the accumulated radiation dameage.

	For the orbital path, the moons of Uranus are quite
small, so there is very little chance of an impact.  Even
an encounter close enough to seriously effect the
trajectory is very unlikely.  For moons of a body not yet
visited, the uncertainty in the orbit is VERY great.
Several orders of magnitude greater than the size of the
bodies, so even if you WANTed to impact one, you'd be hard
pressed.  On its pass through Saturn's system one of the
V's ended up on an impact course with Titan because of
these uncertainties.  They had several days to make the
burn, but there were still plenty of nervous space
scientist types around here at the time.

	There also seems to be plenty of delta-V left worth
of fuel, so any maneuvers to get closer to the moons will
be "no problem".

Article-I.D.: alice.4005
Posted: Thu Jul 18 08:15:43 1985
Date-Received: Fri, 19-Jul-85 02:48:23 EDT
References: <38@escher.UUCP>
Organization: Bell Labs, Murray Hill
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On the subject of Voyager 2's condition, there are two major systems
with problems.  One is the main receiver.  It doesn't work at all.
The backup does work but has problems locking on to Earth-based
signals in certain temperature ranges; JPL people in charge, though,
say they have worked away around this and that it shouldn't pose
a problem.  The other problem is that, during the passby of Saturn,
some damage was sustained in the mechanisms that move the camera
platform, causing it to stick at times.  Again, JPL said that there
should be no problem with this as the platform seems to move just
fine if moved slowly.  Also, they have learned how to point the
cameras by rotating the entire spacecraft.

Article-I.D.: utzoo.5803
Posted: Fri Jul 19 12:12:15 1985
Date-Received: Fri, 19-Jul-85 12:12:15 EDT
References: <1792@aecom.UUCP>, <38@escher.UUCP>
Organization: U of Toronto Zoology
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There is one such uncertainty, associated with the 1989 Neptune encounter
rather than the Uranus encounter:  nobody knows whether Neptune has rings
or not.  There is some evidence that it might.  The trajectory tentatively
planned for the Neptune encounter may have to be revised, because if the
ring reports are true, the trajectory takes Voyager straight into them.

Going to a more conservative trajectory would be a pity, because the Neptune
encounter (unlike the Uranus one) is not constrained by the need to reach
the next planet, and the planned path includes a very close flyby of Triton.
-- 
				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,linus,decvax}!utzoo!henry

Article-I.D.: utzoo.5804
Posted: Fri Jul 19 12:16:36 1985
Date-Received: Fri, 19-Jul-85 12:16:36 EDT
References: <38@escher.UUCP>, <4005@alice.UUCP>
Organization: U of Toronto Zoology
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The problem with the scan platform on Voyager 2 is particularly annoying
for the Uranus encounter, because Voyager is going through the Uranus
system at almost a right angle to the plane of Uranus's moons.  This means
a fairly brief close-encounter phase with interesting objects in several
well-separated directions.  One can safely predict considerable tearing of
hair over the final pointing schedule, given the need to move the platform
slowly if at all.
-- 
				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,linus,decvax}!utzoo!henry

Article-I.D.: bmcg.1746
Posted: Wed Jul 17 11:53:05 1985
Date-Received: Fri, 19-Jul-85 20:15:55 EDT
References: <1792@aecom.UUCP>
Distribution: na
Organization: Burroughs Corp. ASG, San Diego, CA.
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> 	While the publicity builds for Halley's comet, Voyager II is plodding
> steadily at 40,000 mph towards another planetary encounter.
> 	After that it will reach Neptune on Aug 24, 1989, and then be propelled
> downward out of the solar system.  (It's companion, Voyager I was propelled
> upward out of solar system immediately after encountering Saturn)
>>
>> Is Voyager I or II the space craft that the plaque was installed indicating
>> Man, Woman, Earth's position in our solar system, etc?? I forgot.
>>
>> Also, after it leaves our solar system, what type of data will it 
>> transmit back?
>> If it is just going to ramble I can't see justifing to expense but
>> they must have some goal for it don't you think.
>> My opinion is to have it do a wide circle and go back toward Earth.
>> By the time it came back we would have the space shuttle perfected
>> enough to retrieve it. An awful lot of info can be recovered from a
>> returned intersystem vehicle.
>>
>> Anybody care to comment
>>
>>                               --bobn--
>>                                sdcsvax!bmcg!bobn
>>

Article-I.D.: ames.1049
Posted: Sun Jul 21 13:35:43 1985
Date-Received: Tue, 23-Jul-85 19:49:45 EDT
References: <1792@aecom.UUCP> <1746@bmcg.UUCP>
Distribution: na
Organization: NASA-Ames Research Center, Mtn. View, CA
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Xref: tektronix net.space:04033 

> >> Is Voyager I or II the space craft that the plaque was installed indicating
> >> Man, Woman, Earth's position in our solar system, etc?? I forgot.
> >>
> >> Also, after it leaves our solar system, what type of data will it 
> >>                               --bobn--
> >>                                sdcsvax!bmcg!bobn

Pioneer 10/11 have a controversial plack design by Carl Sagan's second
wife showing a pair of naked humans and a crude star map of our galatic
position.  My favorite space-political cartoon by Paul Conrad has two clothed
aliens looking on saying: The people of earth are just like us, except
they're not clothed."

Voyagers 1/2 have record "Sounds of the Planet Earth" which was mentioned
in Star Trek I and Starman with digitized pictures and sounds of earth
as well a map, and a design to build a 'player.'  This was designed by Carl
and his then to be third wife and some one else.  A book was published
entitled
Murmers of Earth, I believe.

--eugene miya
  NASA Ames Research Center
  {hplabs,ihnp4,dual,hao,decwrl,allegra}!ames!aurora!eugene

Article-I.D.: ames.1052
Posted: Mon Jul 22 16:06:37 1985
Date-Received: Tue, 23-Jul-85 19:50:39 EDT
References: <1792@aecom.UUCP> <1746@bmcg.UUCP> <1049@ames.UUCP>
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Organization: NASA-Ames Research Center, Mtn. View, CA
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> > >> Also, after it leaves our solar system, what type of data will it 
> > >>                               --bobn--
> > >>                                sdcsvax!bmcg!bobn

I forgot to answer this:
It will collect data on the nature of interstellar space, the boundary
of the solar system with that space where the solar winds die out.
It will look at phasma and electromagnetics.  This is currently being
done with Pioneer and Voyager I.

--eugene miya
  NASA Ames Research Center
  {hplabs,ihnp4,dual,hao,decwrl,allegra}!ames!aurora!eugene

Article-I.D.: ames.1051
Posted: Mon Jul 22 16:02:03 1985
Date-Received: Thu, 25-Jul-85 07:34:08 EDT
References: <1792@aecom.UUCP>, <38@escher.UUCP> <5803@utzoo.UUCP>
Organization: NASA-Ames Research Center, Mtn. View, CA
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> There is one such uncertainty, associated with the 1989 Neptune encounter
> rather than the Uranus encounter:  nobody knows whether Neptune has rings
> or not.  There is some evidence that it might.  The trajectory tentatively
> planned for the Neptune encounter may have to be revised, because if the
> ring reports are true, the trajectory takes Voyager straight into them.
> 
> Going to a more conservative trajectory would be a pity, because the Neptune
> encounter (unlike the Uranus one) is not constrained by the need to reach
> the next planet, and the planned path includes a very close flyby of Triton.
> -- 
> 				Henry Spencer @ U of Toronto Zoology
> 				{allegra,ihnp4,linus,decvax}!utzoo!henry

There are many uncertainies.  Most are not visible to the naked eye:
radiation belts, large magnetic anomalies from satellites, gravitational
anomalies, intermediate swarms of astroids at a distance we cannot detect.
Some experiements such as the radio astronomy experiments must take place
on the lee side of the planet in order to get some idea which the upper
atmospheres are like.  Too bad the original Grand Tour mission was not
approved.

--eugene miya
  NASA Ames Research Center
  {hplabs,ihnp4,dual,hao,decwrl,allegra}!ames!aurora!eugene
  @ames-vmsb.ARPA:emiya@jup.DECNET

Article-I.D.: kontron.408
Posted: Wed Jul 24 19:37:53 1985
Date-Received: Fri, 26-Jul-85 11:59:32 EDT
References: <1792@aecom.UUCP> <1746@bmcg.UUCP> <1049@ames.UUCP> <1052@ames.UUCP>
Distribution: na
Organization: Kontron Electronics, Irvine, CA
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Xref: tektronix net.space:04048 

> > > >> Also, after it leaves our solar system, what type of data will it 
> > > >>                               --bobn--
> > > >>                                sdcsvax!bmcg!bobn
> 
> I forgot to answer this:
> It will collect data on the nature of interstellar space, the boundary
> of the solar system with that space where the solar winds die out.
> It will look at phasma and electromagnetics.  This is currently being
> done with Pioneer and Voyager I.
> 
> --eugene miya
>   NASA Ames Research Center
>   {hplabs,ihnp4,dual,hao,decwrl,allegra}!ames!aurora!eugene

The more important question (at least to me) is, where is it going to?
I worked on Voyager back around 1976, and I asked one of the researchers
once, "What star is going closest to?  And how close will it get?"  I
got a "We'll get back to" type of response.

So again, nine years later, "Where's it going?"

Article-I.D.: utastro.430
Posted: Sat Jul 27 10:34:39 1985
Date-Received: Sun, 28-Jul-85 05:43:46 EDT
References: <1792@aecom.UUCP> <1746@bmcg.UUCP> <1049@ames.UUCP> <1052@ames.UUCP> <408@kontron.UUCP>
Distribution: na
Organization: U. Texas, Astronomy, Austin, TX
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> 
> The more important question (at least to me) is, where is it going to?
> I worked on Voyager back around 1976, and I asked one of the researchers
> once, "What star is going closest to?  And how close will it get?"  I
> got a "We'll get back to" type of response.
> 
> So again, nine years later, "Where's it going?"

Nowhere.  It is not pointing anywhere near the nearest stars.  By the time
it gets very far all the stars will have moved.  We have no idea where it
might end up, but odds are that it will never pass close to another
planetary system.
-- 

"Don't argue with a fool.      Ethan Vishniac
 Borrow his money."            {charm,ut-sally,ut-ngp,noao}!utastro!ethan
                               Department of Astronomy
                               University of Texas

Article-I.D.: aurora.379
Posted: Tue Jul 30 19:06:40 1985
Date-Received: Fri, 2-Aug-85 10:49:07 EDT
References: <1792@aecom.UUCP> <1746@bmcg.UUCP>
Distribution: na
Organization: NASA Ames Research Center, Mtn. View, CA
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Xref: tektronix net.space:04094 

Regarding Voyager 2 which is heading for Uranus...
> >>
> >> Also, after it leaves our solar system, what type of data will it 
> >> transmit back?
Possibly solar wind data, I'm not sure though.

> >> My opinion is to have it do a wide circle and go back toward Earth.
Not enough propellant by several orders of magnitude.  Sorry.

Article-I.D.: ames.1065
Posted: Wed Jul 31 20:53:47 1985
Date-Received: Fri, 2-Aug-85 13:16:53 EDT
References: <1792@aecom.UUCP> <1746@bmcg.UUCP> <1049@ames.UUCP> <1052@ames.UUCP> <408@kontron.UUCP> <430@utastro.UUCP>
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Organization: NASA-Ames Research Center, Mtn. View, CA
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> > 
> > The more important question (at least to me) is, where is it going to?
> > I worked on Voyager back around 1976, and I asked one of the researchers
> > once, "What star is going closest to?  And how close will it get?"  I
> > got a "We'll get back to" type of response.
> > 
> > So again, nine years later, "Where's it going?"
> 
> Nowhere.  It is not pointing anywhere near the nearest stars.  By the time
> it gets very far all the stars will have moved.  We have no idea where it
> might end up, but odds are that it will never pass close to another
> planetary system.
> -- 
> 

Ah, found it!
Sorry Ethan, this is not entirely true.  While it is true that there is no
deliberate target, someone at JPL [sorry, forgot to copy his name down,
he deserves the credit] calculated the motions of local stars to 100,000
years.  Both Voyagers will pass to around 1 Light-year (approx) of the
star AC +79 3888 in about 40,000 years.  AC +79 3888 is currently 17
light years away and is expected to be about 3 light years away by that time.
[The velocity is left as an excercise to elementary school students...]. ;-)
After Neptune encounter of V 2, a decision will be made whether to use the
remaining manuveuring fuel to improve the current trajectory for a
closer encounter with AC +79 3888.

--eugene miya
  NASA Ames Research Center
  {hplabs,ihnp4,dual,hao,decwrl,allegra}!ames!aurora!eugene
  emiya@ames-vmsb

Article-I.D.: utastro.463
Posted: Thu Aug  1 11:06:38 1985
Date-Received: Sat, 3-Aug-85 04:17:27 EDT
References: <1792@aecom.UUCP> <1746@bmcg.UUCP> <1049@ames.UUCP> <1052@ames.UUCP> <408@kontron.UUCP> <430@utastro.UUCP> <1065@ames.UUCP>
Distribution: na
Organization: U. Texas, Astronomy, Austin, TX
Lines: 29

> > > 
> > > So again, nine years later, "Where's it going?"
> > 
> > Nowhere.  It is not pointing anywhere near the nearest stars.  By the time
> > it gets very far all the stars will have moved.  We have no idea where it
> > might end up, but odds are that it will never pass close to another
> > planetary system.
> 
> Sorry Ethan, this is not entirely true.  While it is true that there is no
> deliberate target, someone at JPL [sorry, forgot to copy his name down,
> he deserves the credit] calculated the motions of local stars to 100,000
> years.  Both Voyagers will pass to around 1 Light-year (approx) of the
> star AC +79 3888 in about 40,000 years.  AC +79 3888 is currently 17
> light years away and is expected to be about 3 light years away by that time.
> [The velocity is left as an excercise to elementary school students...]. ;-)
> After Neptune encounter of V 2, a decision will be made whether to use the
> remaining manuveuring fuel to improve the current trajectory for a
> closer encounter with AC +79 3888.
> 
> --eugene miya

Hmmmmmm..........................  Anyone out there who thinks one light year
counts as close can call me a liar.
-- 

"Don't argue with a fool.      Ethan Vishniac
 Borrow his money."            {charm,ut-sally,ut-ngp,noao}!utastro!ethan
                               Department of Astronomy
                               University of Texas

Article-I.D.: utastro.464
Posted: Thu Aug  1 11:19:15 1985
Date-Received: Sat, 3-Aug-85 04:17:55 EDT
References: <1792@aecom.UUCP> <1746@bmcg.UUCP> <1049@ames.UUCP>
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Organization: U. Texas, Astronomy, Austin, TX
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> > 
> > Sorry Ethan, this is not entirely true.  While it is true that there is no
> > deliberate target, someone at JPL [sorry, forgot to copy his name down,
> > he deserves the credit] calculated the motions of local stars to 100,000
> > years.  Both Voyagers will pass to around 1 Light-year (approx) of the
> > star AC +79 3888 in about 40,000 years.  AC +79 3888 is currently 17
> > light years away and is expected to be about 3 light years away by that time.
> > [The velocity is left as an excercise to elementary school students...]. ;-)
> > After Neptune encounter of V 2, a decision will be made whether to use the
> > remaining manuveuring fuel to improve the current trajectory for a
> > closer encounter with AC +79 3888.
> > 
> > --eugene miya

Actually, something about this puzzles me.  Assuming that the space velocity
of AC +79 3888 is only known to within 1 km/sec I get that even we aimed
something at that star we would expect to miss by 13% of a light year.
This is about a trillion kilometers (about 8000 AU).  Admittedly there
may be no other use for the manuveuring fuel than aiming at AC +79 3888,
but no one could reasonably expect anyone there to notice it as it goes
by.  I'm not much on velocity determinations, but isn't this basically
right?
-- 

"Don't argue with a fool.      Ethan Vishniac
 Borrow his money."            {charm,ut-sally,ut-ngp,noao}!utastro!ethan
                               Department of Astronomy
                               University of Texas

Article-I.D.: alberta.602
Posted: Fri Aug  2 19:58:08 1985
Date-Received: Sun, 4-Aug-85 08:44:18 EDT
References: <1792@aecom.UUCP> <1746@bmcg.UUCP> <1049@ames.UUCP> <1052@ames.UUCP> <408@kontron.UUCP> <430@utastro.UUCP> <1065@ames.UUCP>
Reply-To: andrew@pembina.UUCP (Andrew Folkins)
Distribution: na
Organization: U. of Alberta, Edmonton, AB
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Summary: 

In article <1065@ames.UUCP> eugene@ames.UUCP (Eugene Miya) writes:
>        Both Voyagers will pass to around 1 Light-year (approx) of the
>star AC +79 3888 in about 40,000 years.  

I have this feeling that both spacecraft will be in the Smithsonian long
before then . . .

-- 
Andrew Folkins               YABS : If you think education is expensive, 
ihnp4!alberta!andrew                consider the price of ignorance.

Article-I.D.: ssc-vax.82
Posted: Fri Aug  2 15:08:52 1985
Date-Received: Mon, 5-Aug-85 17:53:36 EDT
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> > 
> > So again, nine years later, "Where's it going?"
> 
> Nowhere.  It is not pointing anywhere near the nearest stars.  By the time
> it gets very far all the stars will have moved.  We have no idea where it
> might end up, but odds are that it will never pass close to another
> "Don't argue with a fool.      Ethan Vishniac
>  Borrow his money."            {charm,ut-sally,ut-ngp,noao}!utastro!ethan
>                                Department of Astronomy
>                                University of Texas

     I believe you are correct that it will never pass close to another
planetary system but for a different reason.  Long before it will get
anywhere significant at all in interstellar terms, someone will go and retrieve
it to put it in the Smithsonian.

     Dani Eder
     Boeing Aerospace Company.
	Advanced Space Transportation Organization
 

Article-I.D.: ukma.2031
Posted: Tue Aug  6 15:32:20 1985
Date-Received: Thu, 8-Aug-85 19:41:33 EDT
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Reply-To: sean@ukma.UUCP (Sean Casey)
Distribution: na
Organization: The White Tower @ The Univ. of KY
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Xref: tektronix net.space:04151 

In article <82@ssc-vax.UUCP> eder@ssc-vax.UUCP (Dani Eder) writes:
>     I believe you are correct that it will never pass close to another
>planetary system but for a different reason.  Long before it will get
>anywhere significant at all in interstellar terms, someone will go and retrieve
>it to put it in the Smithsonian.

I hope so.  I really do.

					"You can't track in Hyperspace."
							- H. Solo
-- 

-  Sean Casey				UUCP:	sean@ukma.UUCP   or
-  Department of Mathematics			{cbosgd,anlams,hasmed}!ukma!sean
-  University of Kentucky		ARPA:	ukma!sean@ANL-MCS.ARPA	

Article-I.D.: hrpd3.282
Posted: Tue Aug  6 10:09:49 1985
Date-Received: Mon, 12-Aug-85 00:10:25 EDT
Organization: Bell Labs, Holmdel NJ
Lines: 12


I have a question .....
	If something the size of a voyager, presumably not radiating
much radio energy, were to enter our solar system from an alien
culture, is the possibility of us detecting it more than miniscule ?

I just wonder it would burn up in the sun unnoticed. If this happens,
it would make all Carl Sagan's artistic work of a man and a woman
rather pointless, and just a waste of NASA's budget.

			Ken Cochran    vax135!hr1ar!ken

Article-I.D.: baylor.375
Posted: Mon Aug 12 18:01:17 1985
Date-Received: Wed, 14-Aug-85 07:29:11 EDT
References: <1792@aecom.UUCP> <1746@bmcg.UUCP> <1049@ames.UUCP>
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Organization: Ancient Illuminated Seers of Bavaria
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> In article <82@ssc-vax.UUCP> eder@ssc-vax.UUCP (Dani Eder) writes:
> >     I believe you are correct that it will never pass close to another
> >planetary system but for a different reason.  Long before it will get
> >anywhere significant at all in interstellar terms, someone will go and retrieve
> >it to put it in the Smithsonian.
> 
> I hope so.  I really do.

I second that emotion.
-- 
	Peter da Silva (the mad Australian)
		UUCP: ...!shell!neuro1!{hyd-ptd,baylor,datafac}!peter
		MCI: PDASILVA; CIS: 70216,1076

Article-I.D.: aurora.382
Posted: Thu Aug 15 17:53:38 1985
Date-Received: Mon, 19-Aug-85 22:16:35 EDT
References: <282@hrpd3.UUCP>
Organization: NASA Ames Research Center, Mtn. View, CA
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> 
> I have a question .....
> 	If something the size of a voyager, presumably not radiating
> much radio energy, were to enter our solar system from an alien
> culture, is the possibility of us detecting it more than miniscule ?
> 
> I just wonder it would burn up in the sun unnoticed. If this happens,
> it would make all Carl Sagan's artistic work of a man and a woman
> rather pointless, and just a waste of NASA's budget.
> 

Not a waste at all.  As was recognized at the time, the chance of 
extraterestrials seing the work is miminal, but the work has been viewed
by thousands, if not millions, of us earthlings.

Article-I.D.: ihnp3.140
Posted: Fri Aug 16 18:14:29 1985
Date-Received: Tue, 20-Aug-85 21:14:08 EDT
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Reply-To: dhp@ihnp3.UUCP (45262-Douglas H. Price)
Distribution: na
Organization: AT&T Bell Laboratories
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Keywords: solar system close approach
Summary: AC +79 3888, how close?

That brings up an interesting point.  How close (and when) will star AC +79 3888
be at its closest approach to the solar system?  Which stars (that are currently
being tracked) will approach closer than 3 light years in the next 100,000 years?


-- 
						Douglas H. Price
						Analysts International Corp.
						@ AT&T Bell Laboratories
						..!ihnp4!ihnp3!dhp

Article-I.D.: psivax.671
Posted: Wed Aug 21 16:17:26 1985
Date-Received: Sun, 25-Aug-85 01:37:38 EDT
References: <1792@aecom.UUCP> <1746@bmcg.UUCP> <1049@ames.UUCP>
Reply-To: friesen@psivax.UUCP (Stanley Friesen)
Distribution: na
Organization: Pacesetter Systems Inc., Sylmar, CA
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Summary: 

In article <464@utastro.UUCP> ethan@utastro.UUCP (Ethan Vishniac) writes:
>
>Actually, something about this puzzles me.  Assuming that the space velocity
>of AC +79 3888 is only known to within 1 km/sec I get that even we aimed
>something at that star we would expect to miss by 13% of a light year.
>This is about a trillion kilometers (about 8000 AU).  Admittedly there
>may be no other use for the manuveuring fuel than aiming at AC +79 3888,
>but no one could reasonably expect anyone there to notice it as it goes
>by.  I'm not much on velocity determinations, but isn't this basically
>right?
>-- 
	Well, there is another reason why no-one is likely to notice
them. If I remember my stellar naming conventions and relative
magnitudes correctly, that star is likely to be a *very* dim type 'M'
dwarf. A planet would have to be closer to it than Mercury is th the
Sun to even have a hope of liquid water, let alone a reasinable
atmosphere, so - *no* life at all to notice anything. Sigh, wouldn't
Tau Ceti have been better? :-)

	Well, I guess it *could* be a low end type 'K' - still not
much hope for life though.
-- 

				Sarima (Stanley Friesen)

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