HDTenEightyP/NetNews huggingface dataset:
From: asnd@msr.triumf.ca (Donald Arseneau)
Newsgroups: sci.astro,sci.space
Subject: Dyson sphere
Date: 14 Oct 1992 21:48 -0700
Organization: TRIUMF: Tri-University Meson Facility
Distribution: world
NNTP-Posting-Host: msr.triumf.ca
News-Software: VAX/VMS VNEWS 1.41    

In article <1992Oct14.233332.4735@infodev.cam.ac.uk>, sl25@cus.cam.ac.uk (Steve Linton) writes...

% I don't think you want a reflective Dyson sphere, for reasons discussed
% much further back in the NewsGroup (you cook the inner planets). For a
% loss of 50% of your lift you can make do with a black one which also
% enables you to convert all the solar energy into something useful (Dyson's
% original reason for proposing the sphere). 

But the light bounces around to the other side and will still get absorbed 
eventually.  If the sphere is 80% reflective, there will be 4 x 2 = 8
times the pressure as for a black sphere.

But what about the sun in the center?  I think the outer layers would heat 
up a lot. Would that cause a huge solar wind?  Anyone want to speculate?

Donald Arseneau       asnd@reg.triumf.ca
Newsgroups: sci.astro,sci.space
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: Diesen sphere or Strungen Sphere
Date: Wed, 14 Oct 1992 05:20:07 GMT
Organization: U of Toronto Zoology

In article <Bw2zHD.AvI@news.cso.uiuc.edu> jbh55289@uxa.cso.uiuc.edu (Josh 'K' Hopkins) writes:
>A Dyson sphere with a radius of one A.U. (as postulated in the Start Trek 
>episode to which the poster refered - it's also a nice round number) and 1 km
>thick would require about 10e17 cubic km of materials. 
>
>Earth has a volume close to 10e12 cubic km.  Jupiter is about 100 times bigger.

So don't make it 1 km thick.

There really isn't any reason to make the thing any thicker than what you
need to hold atmosphere and provide shielding.  You're not going to get
any useful amount of gravity out of any practical thickness.

In practice, if you look at Dyson's *original* proposal, he wasn't
suggesting a solid one-piece sphere at all, partly because it presents
tremendous structural challenges.  He was proposing a swarm of smaller
bodies, each individually in orbit, which together would intercept almost
all of the output of the star.
-- 
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  henry@zoo.toronto.edu  utzoo!henry
Newsgroups: sci.astro
From: randolph@est.enet.dec.com (Tom Randolph)
Subject: Re: Mars Observer and the "Face"
Organization: Digital Equipment Corporation
Distribution: na
Date: 12 OCT 92 16:19:40    


In article <1992Oct12.124423.1@stsci.edu>, gawne@stsci.edu writes...
>Oh boy.  Along these lines, I've looked thru my Atlas of Mars trying to
>find this "feature" without success.  Perhaps someone can point me to
>a specific page and map?  Or did the face come from the same survey that
>showed us the dinosaurs that resembled iguanas?
> 
>I've always pretty much assumed that the "face" represents a curious
>combination of crater, interior features, and shadows.
> 
>-Bill Gawne,  Space Telescope Science Institute

Viking photo numbers for the two pictures of it are: 35A72  and  70A13.
I have the data that goes with the two photos, and a blown-up .GIF, if anyone's
interested. Er, "Areographically", it's about 1 km in size, in the Cydonia
region. Photographically, Viking only managed images of it about 30x40 pixels
in size. Hence, raging controversy ever since the UFO community latched onto it
(Richard Hoagland in particular, who wrote a whole book: "Monuments of Mars, a
City on the Edge of Forever").

I've also heard that NASA is planning a picture or two of it, but it'd be nice
to hear it from the horse's mouth... Me, I'd photograph the damn thing every
possible orbit... maybe we'd squash a myth once and for all.

-Tom R.   randolph@est.enet.dec.com
From: seymour@ast.saic.com (Ken Seymour)
Newsgroups: sci.astro
Subject: Re: Radio Telescopes
Date: 9 Oct 92 19:17:48 GMT
Organization: SAIC

In article <1992Oct8.105453.10254@bsu-ucs.uucp> 00csriggle@bsu-ucs.uucp writes:
>Hi... Me and some other people are attempting to build a "minor" radio
>telescope. Just wondering if anyone had ideas on whether to get a shortwave
>from someone or to build one ourselves? If it's a good idea to buy one, is
>there a good place to get one?
>
>
>Chad Riggle

You might check rec.radio.shortwave.  They are always discussing
different brands.  There is also a magazine called Popular
Communications that discusses scanners and shortwave radio.  
Naturally, they have lots of mail order adds etc.
Radio Shack sells shortwave radios.  

Ramsey Electronics sells kits of 10, 20, 40, and 80 meter low power 
recievers for about $40 (if you buy the plastic enclosure as well).  
I built the 40 meter kit and it works.  Bug me if you want their 
address or phone number.

To get good performance from a shortwave radio, one usually attaches a 
long length of wire (most of which should be outdoors) to either an 
external antenna jack or clipped onto the built-in antenna.
If you know what band you are going to use, you can get better gain by
cutting the length of the wire to lambda/2 and raising it at least
lambda/4 off the ground (where lambda is the wavelength of the band).
Some more complicated antennas would be more directional.

I wonder about using shortwave frequencies for radio astronomy.  World
Wide shortwave works precisely because the ionosphere refracts shortwave
radio waves back to the earth.  On any given night, there is a Maximum
Usable Frequency (MUF).  Radio waves above this frequency are not
refracted enough to return back to earth and go out in space.

The D layer of the ionosphere absorbs radio waves at some frequencies.  
This effect occurs mostly in the daytime and effects waves
with a wavelength > 20 meters or so.  Wavelengths of 10 to 20 meters
should not have this problem.

Radio waves comming in from space with an angle of incidence at or near
zero would not be refracted much and could be received by a shortwave
radio.

You may want to record reports of solar phenomenom to correlate with
your data.  The important quantities I can think of would be solar flux
and sunspot number.

Most space communications takes place at much higher frequencies that
are not effected by the ionosphere so much.

Anyway, enough rambling.
-- 
Ken Seymour
seymour@ast.saic.com
From: harmons@mithril.wv.tek.com (Harmon Sommer)
Newsgroups: sci.astro
Subject: A 100 Billion?
Date: 13 Oct 92 17:49:13 GMT
Reply-To: harmons@mithril.wv.tek.com (Harmon Sommer)

A local newspaper article on SETI mentioned that there are 100 Billion stars
in our solar system. How is this quantity arrived at? 
Newsgroups: sci.astro
From: apoyner@as.arizona.edu (Tony Poyner)
Newsgroups: sci.astro
Subject: Re: THE TRUE CAUSE & ORIGIN OF EARTHQUAKES
Date: 15 Oct 92 16:07:34 GMT
Reply-To: apoyner@as.arizona.edu
Organization: MMT Observatory, Univ.of Arizona

Have you ever NOTICED that the more UNBELIEVABLE or PREPOSTEROUS an
article is, the more USE the author makes of CAPITALIZATION?

---
Tony Poyner                               apoyner@as.arizona.edu
Multiple Mirror Telescope Observatory     Tel   (602) 621-5185
Univ. of Arizona, Tucson, AZ 85721        Fax   (602) 670-5740
Organization: Johannes Kepler University Linz - Computing Center
Date: Tuesday, 13 Oct 1992 10:27:34 CET
From: Herbert Raab <K3032E0@ALIJKU11.BITNET>
Newsgroups: sci.astro
Subject: Re: Fireball, Meteorite
Distribution: na

 <1992Oct12.165433.16365@ncrcae.ColumbiaSC.NCR.COM>

I saw a picture of the car that was hit by the meteorite last Friday in an
Austrian (|) newspaper. They said that the meteor was videotaped by a TV-
station, so the "brigt green meteor" was probably caused by this piece of rock
coming in. Can somebody confirm this?

They also wrote that a meteorologist (|) said the meteor was part of a shower
which is observed each year on October 9. I doubt this, because until now none
of the known meteor-showers delivered a meteorite.

By the way, I believe meteorites feel COLD when they come down, too. I read
about a stony meteorite (which fell in Canada, as far as I can remember) whose
fusion crust was covered with ICE when it was found on a warm summer day,
because the stone was still that cold inside.

Sad enough, nobody can tell when and where such a space-rock lands. I surely
would sacrify my car to get one more piece... :)

  Greetings
    Herbert Raab
  >>K3032E0 @ EDVZ.UNI-Linz.AC.AT<< >>K3032E0 @ ALIJKU11.BITNET<<
Newsgroups: sci.astro
From: fischer@physun.physics.mcmaster.ca (Phil Fischer)
Subject: Re: UFO EVIDENCE VS. Carl Sagan
Organization: Dept. of Physics & Astronomy, McMaster University
Date: Fri, 16 Oct 1992 01:05:31 GMT

In article <1992Oct14.104249.18835@kth.se> TordM@VanA.PhySto.SE writes:

>In article <1992Oct13.175901.1730@cnsvax.uwec.edu>, mcelwre@cnsvax.uwec.edu
writes:

>
>>               The Roswell Incident illustrates a serious problem here.  
>>          Whenever there IS physical evidence of a UFO Spacecraft, the 
>>          military always confiscates it, using "national security" as 
>>          an excuse, and then ACTS LIKE THE MAFIA toward the finders 
>>          and other witnesses by THREATENING them if they don't keep 
>>          silent!  (They did it to the rancher in the Roswell 
>>          Incident.) 
>
> AND the COUNTRIES that DON'T HAVE any MILITARY ??
>

Just out of curiosity, which are these?

-- 
Phil Fischer                         | Hamilton, Ont.
fischer@crocus.physics.mcmaster.ca   | Canada
Dept. of Physics and Astronomy       | L8S 4M1
McMaster University                  | 416-525-9140 X 4574
From: wats@scicom.AlphaCDC.COM (Bruce Watson)
Newsgroups: sci.astro
Subject: Re: Observing Venus in daylight
Date: 6 Oct 92 18:03:33 GMT
Organization: Alpha Science Computer Network, Denver, Co.

In article <1992Oct6.092157.10785@hsr.no| frank@hsr.no (Frank A Stevenson) writes:
|
|	Venus now as a solar elongation of more than 30 degrees, and a visual
|magnitude of app. -3.3. I have been trying to observe Venus in broad daylight
|with 12x50 binoculars and after sunset. I live 59 degrees north and Venus has an
|altitude of only 3.9 degrees at sunset, and sets 30 minutes after the Sun. I
|think that conditions are unfavourable for observing after sunset.
|
|	I would like to hear from people who have observed Venus in daylight
|under similar conditions in order to find out what I am doing wrong. Have I
|simply overlooked Venus or is the apperature to small. Any help would be
|appreciated.
|
The problem is with this particular elongation. In the northern hemisphere
autumn the ecliptic rises slowly from the sun at sunset in the westerly
direction. As you say, Venus is too close to the horizon and its light
is traversing the thickest, cloudiest, haziest part of the earth's 
atmosphere. Keep trying, but you may have to wait until after the
first of the year when the planet higher in the sky and brighter.

-- 
Bruce Watson (wats@scicom)  Tumbra, Zorkovick; Sparkula zoom krackadomando.  
Newsgroups: sci.astro
From: sallen@nyx.cs.du.edu (Steve Allen)
Subject: CCD Camera ST-4   and the MAc
Organization: Nyx, Public Access Unix @ U. of Denver Math/CS dept.
Date: Thu, 15 Oct 92 18:05:33 GMT

Hi all,
     Ive just started a final year Astronomy project, involving the
setting up and use of the ST-4 CCD camera from S-Big.
 
I am simply calling for advice and tips from any users, especially
those who use the camera in connection with an Apple Mac computer.
 
I am at present trying to sort out the problem of file transfer from their 
unique file format to GIF or FITS.

Thanks alot ,    Please respond to my email address please,

Ant.    pm3ah@sunc.sheffield.ac.uk

Newsgroups: sci.astro,rec.radio.amateur.misc,rec.radio.shortwave
From: oler@rho.uleth.ca (Cary Oler)
Subject: Daily Solar Geophysical Data Broadcast for 11 October
Organization: University of Lethbridge
Date: 12 Oct 92 06:19:41 GMT

!!BEGIN!! (1.0) S.T.D. Solar Geophysical Data Broadcast for DAY 285, 10/11/92
10.7 FLUX=110.5  90-AVG=120        SSN=090      BKI=3324 3332  BAI=014
BGND-XRAY=B2.7     FLU1=8.5E+05  FLU10=1.0E+04  PKI=2214 4443  PAI=016
  BOU-DEV=021,020,012,056,038,027,029,015   DEV-AVG=027 NT     SWF=00:000
 XRAY-MAX= C8.3   @ 0209UT    XRAY-MIN= B2.4   @ 1452UT   XRAY-AVG= B5.3
NEUTN-MAX= +002%  @ 1410UT   NEUTN-MIN= -002%  @ 2355UT  NEUTN-AVG= -0.2%
  PCA-MAX= -2.9DB @ 0520UT     PCA-MIN= -3.6DB @ 1435UT    PCA-AVG= -3.1DB
BOUTF-MAX=55430NT @ 2205UT   BOUTF-MIN=55385NT @ 1910UT  BOUTF-AVG=55416NT
GOES7-MAX=P:+088NT@ 1736UT   GOES7-MIN=N:-009NT@ 1122UT  G7-AVG=+069,+037,+007
GOES6-MAX=P:+093NT@ 2229UT   GOES6-MIN=E:-021NT@ 1607UT  G6-AVG=+078,-010,+031
 FLUXFCST=STD:110,110,105;SESC:110,110,105 BAI/PAI-FCST=010,015,015/015,015,025
    KFCST=1224 5221 2345 5432  27DAY-AP=009,010   27DAY-KP=2323 2232 3333 2221
 WARNINGS=*SWF
   ALERTS=**SWEEP:II=3@0211UTC
!!END-DATA!!
From: ryba@ll.mit.edu (Marty Ryba)
Newsgroups: sci.astro
Subject: Re: Meteoryite hits car in New York state
Date: 14 Oct 92 18:06:13 GMT
Reply-To: ryba@ll.mit.edu (Marty Ryba)
Organization: Group 101, MIT Lincoln Lab.
Originator: ryba@ll.mit.edu (Marty Ryba)


In article <92288.29126.L629159@LMSC5.IS.LMSC.LOCKHEED.COM>, L629159@LMSC5.IS.LMSC.LOCKHEED.COM writes:
|> 1. Assume the meteorite described in this thread is
|> approximately spherical with a diameter of 30 cm, and
|> that it has a mass of 13000 gm (given in original
|> post).
|> 
|> 2. Compute density.
|> 
|> 3. Laugh
|>
|> Al Moore

  Why?  I got a density of 0.92 g/cc, which is slightly below water density.
Considering your size estimate can easily be off by a factor of 2, which
translates into a factor of *eight* in density, I see no problem.

d = 30cm => r = 15 cm (did you forget this step??)
4/3*pi*r^3 = 14 x 10^3 cc
m = 13000 g

density = 13000 / 14000 = 0.92

-- 
Dr. Marty Ryba                     |	Generation X:
Group 101 - Air Defense Techniques |
MIT Lincoln Laboratory             |  Too young to be cynical,
ryba@ll.mit.edu                    |		too old to be optimistic.
Newsgroups: sci.astro,rec.radio.amateur.misc,rec.radio.shortwave
From: oler@rho.uleth.ca (Cary Oler)
Subject: Daily Solar Geophysical Data Broadcast for 07 October
Organization: University of Lethbridge
Date:  8 Oct 92 19:50:26 GMT

!!BEGIN!! (1.0) S.T.D. Solar Geophysical Data Broadcast for DAY 281, 10/07/92
10.7 FLUX=136    90-AVG=122        SSN=161      BKI=1334 2212  BAI=010
BGND-XRAY=B6.1     FLU1=7.0E+05  FLU10=1.3E+04  PKI=2344 2212  PAI=011
  BOU-DEV=005,032,034,062,010,019,008,012   DEV-AVG=022 NT     SWF=04:014
 XRAY-MAX= M3.1   @ 0507UT    XRAY-MIN= B4.4   @ 1434UT   XRAY-AVG= C1.2
NEUTN-MAX= +003%  @ 2320UT   NEUTN-MIN= -004%  @ 0115UT  NEUTN-AVG= -0.4%
  PCA-MAX= -1.4DB @ 1245UT     PCA-MIN= -3.6DB @ 1945UT    PCA-AVG= -3.1DB
BOUTF-MAX=55429NT @ 1347UT   BOUTF-MIN=55395NT @ 1759UT  BOUTF-AVG=55419NT
GOES7-MAX=P:+114NT@ 1938UT   GOES7-MIN=N:-021NT@ 0848UT  G7-AVG=+076,+038,+007
GOES6-MAX=P:+121NT@ 1938UT   GOES6-MIN=E:-023NT@ 1629UT  G6-AVG=+083,-012,+029
 FLUXFCST=STD:135,130,130;SESC:135,135,130 BAI/PAI-FCST=010,010,010/012,020,020
    KFCST=1234 4322 1234 4222  27DAY-AP=090,035   27DAY-KP=5787 5655 6564 4433
 WARNINGS=
   ALERTS=
!!END-DATA!!
From: j.jahn@abbs.hanse.de (Jost Jahn)
Newsgroups: sci.astro
Subject: Sunspots at 14.10.1992.
Reply-To: j.jahn@abbs.hanse.de
Date: 14 Oct 92 20:03:00 MET
Distribution: sci
Organization: ABBS AstroMail, D-W 2121 Dahlenburg / Germany
X-Version: ZerUU V6.45c

Sunspots at 14.10.1992., 0 h UT.

No.    Pos.  Cl.  Ar.  Mag. SF  F  M  X
---------------------------------------
7306 08S 59W Cao   60   b
7307 18S 14W Bxo   10   b
7309 16S 25W Cro   10   b
7310 09N 53E Bxo   10   b    4
7311 17S 60E Axx   10   a    1


No optical or x-ray flares yesterday observed.


 
--
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From: rabjab@golem.ucsd.edu (Jeff Bytof)
Newsgroups: sci.astro
Subject: Re: Mars Observer and the "Face"
Date: 14 Oct 92 18:32:06 GMT
Organization: ucsd
NNTP-Posting-Host: lutherlab.ucsd.edu


>What is the estimated resolution of the MO hires camera?  At first I was
>suprised that they could image a Lander but thinking about it now, Orbiter
>imaged a Surveyor on the Moon so I expect MO would do equally as well.

The expected best resolution for the high-res camera is 1.4 meters.

------------------------
rabjab@golem.ucsd.edu
From: alfa@csource.oz.au (glenn durden)
Newsgroups: sci.astro
Subject: Re: Comet Swift-Tuttle..diameter ???
Date: Fri, 09 Oct 92 16:17:54 +1000
Reply-To: alfa@csource.oz.au
Organization: Unique Computing Pty Ltd, Melbourne, Australia

andromed@cs.dal.ca (Mike Boschat) writes:

>
>  Can anyone who saw Swift-Tuttle recently  like last night or a day or so
> before tell me its diameter in arc minutes ? I know its about 8.6 as of the 7
> but could not locate it..
>  thanks in advance...


Better still, can someone post an ephemeris for Swift-Tuttle, for the folks
(like me) who havnt seen it yet.
P.S.  Dont point me to an American astronomy magazine either, they take a
little time to work their way to the other side of the planet.

.........................................................
glenn durden
alfa@csource.oz.au  Unique Computing Pty Ltd, Melbourne, Australia
The opinions expressed above are that of the author only.
From: syee@Bonnie.ICS.UCI.EDU
Subject: (none)
Newsgroups: sci.astro
Date: 9 Oct 92 04:38:43 GMT


Subject: Re: Clinton and Space Funding

In article <Bv90sJ.C3F@mentor.cc.purdue.edu> hrubin@pop.stat.purdue.edu (Herman Rubin) writes:
>
>There is another, and extremely important, reason for colonization, namely,
>escape from an oppressive government.  The Spanish colonies were moderately
>successful only where they were eminently profitable; the missions in
>California must be considered a failure.  The French colonies in Canada
>and Louisiana were not particularly successful.  On the other hand, the
>English colonies to escape oppression were generally quite successful,
>even bringing in others.  A major part of the US immigration in the 19th
>century was to escape oppression.


I have one simple question.
If you're trying to "...escape from an oppressive government.", how are you
going to escape from this "oppressive government" when they're funding this
project?

Keep searching until a group of private corporations get together and fund a
majority of this project.


					syee@ics.uci.edu


Newsgroups: sci.astro
From: pgf@delcano.mit.edu (Peter G. Ford)
Subject: Re: orbital tilts info
Reply-To: pgf@space.mit.edu
Organization: MIT Center for Space Research
Date: Fri, 16 Oct 1992 21:56:20 GMT

In article <1992Oct15.150918.1@cs1.lamar.edu>, carlis_jc@cs1.lamar.edu writes:
> Could someone out there provide me with an info source for orbital tilts of 
> natural satilites within the solar system? Thank you.

The standard reference for this sort of thing is the "Nautical Almanac",
published jointly each year by the US Naval Observatory and by the Royal
Greenwich Observatory. Look in Section F, "Satellites: Orbital Data", and
the column "Orbital Inclination to Planetary Equator (degrees)". This
covers the major satellites. The smaller ones are described later in the
same section.
From: olle@astro.uu.se (Olof Morell)
Newsgroups: sci.astro
Subject: Days of the Week   Was: exit <sic!>
Date: 12 Oct 1992 15:11:28 GMT
Organization: Uppsala University
Distribution: world
NNTP-Posting-Host: solaris.astro.uu.se

In article <1992Oct9.082758.1628@cnsvax.uwec.edu>, elliottb@cnsvax.uwec.edu writes:

A couple of corrections:

|> The days of the week get their names from the sun, moon, and planets.
|> Sunday = sun
|> Monday = moon
|> Tuesday = mars

Tuesday = Tyr's dag Asa god of ??? (don't remember)

|> Wednesday = mercury
|> Thursday = jupiter

Thursday = Tor's day, Asa god of thunder

|> Friday = venus

Friday = Frej's day, Asa god of fertility (only?)

|> Saturday = saturn

The latin names (French, Spanish) refers to Jove and Mars,
but the english names comes from the nordic, viking, tradition.

*** Olle ***
----------------------------------------------------------------------
E-mail - Olle.Morell@astro.uu.se

Snail Mail - Astronomical Observatory, Box 515, 751 20 Uppsala, Sweden
From: liu@cs.umd.edu (Yuan Liu)
Newsgroups: sci.astro
Subject: Re: Bright Green Fireball
Date: 12 Oct 92 18:50:12 GMT
Reply-To: liu@cs.umd.edu
Distribution: na
Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742

In article <1992Oct12.165433.16365@ncrcae.ColumbiaSC.NCR.COM> greg@korg3.columbiasc.ncr.com (Greg Porr) writes:
# In article <1992Oct12.085326.1@scivax.stsci.edu> gliba@scivax.stsci.edu writes:
# >   A bright green fireball was seen over several states on friday night.
# 

I saw it here in College Park, Maryland.  Although it was cloudy at the time
(7:50 pm), I could still see a bright object moving behind the cloud at a speed
much faster than you'd expect of an airplane.  I could only see the thing
through breaks in the cloud so I didn't see much of the trail, but the
object itself is very bright.  The only thing I can compare to is the
headlights on a low flying airplane when it's coming straight towards you.
It went from the southwestern sky towards the north or northeast at an
elevation of about 35 to 45 degree.  About half way through the sky, it broke
up into several parallel streaks of diminishing light trails and then the show
was over.

This is the first time ever that I see a display like this.  Needless to say I
was quite excited.

Yuan Liu
liu@cs.umd.edu
Newsgroups: sci.astro
From: palmer@sfu.ca (Leigh Palmer)
Subject: Re: rumor concerning Saturn's rings
Organization: Simon Fraser University
Date: Wed, 14 Oct 1992 03:23:28 GMT

In article <1992Oct13.083218.1@stsci.edu> gawne@stsci.edu writes:

>Galileo reported seeing something extending away from Saturn that he
>described as being like ears.  Apparently Huygens was the first person
>to make the mental leap required to recognize that he was looking at 
>a ring around a planet.
>
>As for naked eye visibility of the rings?  I doubt it.  The human eye
>can't resolve Jupiter's moons, and the angular resolution needed for that
>task is a factor of three or so less than the angular resolution necessary
>to resolve Saturn's rings from the planet.  The fundamental limit is an
>aperture (pupil) size of 7mm at the most.  Even Galileo's little telescope
>more than doubled the aperture.

I'm puzzled by the claim that the eye can't "resolve" Jupiter's moons. At 
least some of the galilean moons are resolved by the educated naked eye.
I don't understand what the factor of three refers to; the Jovian system
appears many more than three times as wide as Saturn and his rings.

If one knows that there are rings around Saturn then one will see rings 
with a telescope like Galileo's, even at 20 power. Galileo didn't know
there were rings; that's why he couldn't see them. That's what I mean by
an "educated" eye.

Leigh