HDTenEightyP/NetNews huggingface dataset:
From: baalke@kelvin.jpl.nasa.gov (Ron Baalke)
Newsgroups: sci.astro
Subject: Re: Earth's Orbit if no other planets
Date: 17 Dec 92 00:42:49 GMT
Article-I.D.: elroy.1992Dec16.164700.6478
Reply-To: baalke@kelvin.jpl.nasa.gov
Organization: Jet Propulsion Laboratory
News-Software: VAX/VMS VNEWS 1.3-4

In article <7460061@hpfcso.FC.HP.COM>, duanej@hpfcso.FC.HP.COM (Duane Jacobson) writes...
>>If all the other planets were to suddenly disappear, the Earth's orbit
>>WOULD be very slightly different in the future.  The gravitational
>>attraction of the planets "perturbs" the orbit of the centre of mass
>>of the Earth/Moon system from the keplerian ellipse it would otherwise
>>follow around the sun.  Unless you're interested in predicting precise
> 
>In fact, this is how the existence of Pluto was discovered.  Neptune's
>orbit was perturbed in a way that could most easily be explained by the
>existence of a small planet in a nearby orbit.  So they looked for it and
>found it.

Actually, they were looking for a much larger planet, but instead found
Pluto by accident.  Pluto is much too small to account for the pertubations
seen in Neptune's orbit.  
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | baalke@kelvin.jpl.nasa.gov
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Choose a job you love, and
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | you'll never have to work
|_____|/  |_|/       |_____|/                     | a day in you life. 
Newsgroups: sci.astro
From: cnolan@alex (chris nolan)
Subject: Purchasing a portable telescope
Organization: Trinity University, San Antonio TX, USA
Date: Tue, 15 Dec 1992 17:01:30 GMT

I am currently looking to purchase a telescope that will be quite portable and 
take up a minimum of storage space.  For my price range, I have been 
considering a Celestron C-90 or a Meade 2045D.  I am wondering if anyone who
has experience with either of these two scopes could give me feedback on them,
in particular:
    --does the lack of a standard equatorial mount on the C-90 make it too
difficult for lengthy, if casual, observing?  I don't plan to need any photo
capabilities, but I wonder if a spotting scope design would become tedious in
time.
    --can the tabletop tripod of the Meade be used easily, or does one really
require a field tripod?  Without a tripod, what type of table does one use to
get a stable base?  A folding table sounds a little unwieldy.

Also, I will do quite a bit of viewing from a relatively light-polluted area.
Is the small cat design ok for this type of location, or would I be better
off looking at small refractors?  My main interests are lunar/planetary, though
I enjoy some deep-sky targets as well.


Thanks for any other information about these or other such portable telescopes
you would happen to recommmend.

Chris Nolan
Trinity University 
Newsgroups: sci.astro
From: dwells@fits.cv.nrao.edu (Don Wells)
Subject: Re: Universal time 
Organization: nrao
Date: Thu, 17 Dec 1992 23:47:37 GMT

In article <724620341snz@chrism.demon.co.uk> chris@chrism.demon.co.uk
(Chris Marriott) writes:
   In article <35916@sophia.inria.fr> buffet@gandalf.inria.fr writes:
   GB>does it exist somewhere on the net a universal time server,
   GB>and if yes, how to use it ?
   GB>We do not need high precision. (10 -e02 second will be enough)

 CM> I strongly suspect that getting time to an precision of 0.01s is
 CM> impossible on the Internet, given the fact the packets are
 CM> dynamically routed, and two packets sent out consecutively from
 CM> the host might take totally different routes in their journey to
 CM> you, with non-predictable delays at each routing node.  I think
 CM> you'd be lucky to get the time right to within *one* second!  

Precision distribution of time across the Internet has been an
operational reality for several years, using NTP [Network Time
Protocol]. Master ("stratum 1") servers exist in (all?) regional nets
of the NSFnet and in most regional nets worldwide, probably including
the UK.  It is not unusual to maintain synchronism using NTP with a
tolerance of <0.01s for extended periods in a turbulent wide-area
context. NTP servers compare their local clocks to a *set* of peer
servers, and use an adaptive filter to construct a robust estimate of
the time and frequency offsets of the local clock, and they servo the
clock according to this estimate on a timescale of hours. 

The basic mechanism is the exchange of timestamped packets, sometimes
humorously referred to as "chronons". Changes of route will not matter
other than at the moment of transition, but assymetric routes will
cause bias and/or instability in the estimators.  An assymetry is
likely to be detected in the context of a *set* of servers so that the
erroneous measurements can be rejected in the adaptive filters.
Assymetric routes are rare in most parts of the Internet, and are
generally regarded as bogus configurations.
 
NTP works. I strongly recommend it to anyone who is interested in
maintaining good clocks in computers on the Internet. NTP
implementations exist for essentially all popular Unix computers, and
also for the VxWorks real-time OS, the TGV Multinet VMS TCP-IP
package, and IBM's VM/CMS.

Some manufacturer's are beginning to include NTP support in their
standard OS/networking products (e.g., probably the next Solaris
release), and many people believe that NTP will soon achieve de facto
if not de jure standard status in the worldwide computer industry.

The comp.protocols.time.ntp newsgroup discusses NTP.

Take a look at the anonFTP server on louie.udel.edu.
--

Donald C. Wells             Associate Scientist        dwells@nrao.edu
National Radio Astronomy Observatory                   +1-804-296-0277
520 Edgemont Road                                 Fax= +1-804-296-0278
Charlottesville, Virginia 22903-2475 USA            78:31.1W, 38:02.2N 
Newsgroups: sci.astro
From: chris@chrism.demon.co.uk (Chris Marriott)
Subject: Re: Hubble constant 
Distribution: world
Organization: None
Reply-To: chris@chrism.demon.co.uk
X-Mailer: Simple NEWS 1.90 (ka9q DIS 1.19)
Date: Sat, 12 Dec 1992 13:31:27 +0000

In article <2268.857.uupcb@almac.co.uk> donald.mcintyre@almac.co.uk writes:

>
>>I heard recently that there was new evidence just published somewhere
>>pinning the Hubble constant to about 60 km/sec/megaparsecs. Can anyone
>>comment on how this relates to estimates on the time from the Big
>>Bang?
>
>The following articles may be of interest:
>
>The Hubble Constant
>Huchra, John P.
>Science 256 (17 April 1992) 321-325
>
>The Hubble constant takes the low road again
>Travis, John
>Science 257 (3 July 1992) 34
>Research News
>---
> . DeLuxe. 1.25 #12084 . 
>                                             
>

-- 

Presumably a lower Hubble constant makes the universe bigger ('cos red-shifts
correspond to larger distances), hence older?

--------------------------------------------------------------------------
| Chris Marriott                   | chris@chrism.demon.co.uk            |
|                                  | BIX: cmarriott                      |
| (Still awaiting inspiration      | CIX: cmarriott                      |
|  for a witty .sig .... )         | Compuserve: 100113,1140             |
--------------------------------------------------------------------------
 
Newsgroups: sci.astro
From: mcovingt@aisun3.ai.uga.edu (Michael Covington)
Subject: Re: New Solar Eclipse Circulars!
Summary: New eclipse book
Organization: AI Programs, University of Georgia, Athens
Date: Fri, 11 Dec 1992 18:22:05 GMT


What's more, Cambridge University Press is going to publish a book on
eclipse observing, with contributions by me, Jay Pasachoff, and Fred
Espenak.  It will cover the solar and lunar eclipses for the rest of the
century, with emphasis on the 1994 and 1999 solar eclipses in North
America and Europe respectively.

Tentative title: _Cambridge Eclipse Photography Handbook_.

(In 1999, in case you hadn't noticed, there will be a total eclipse whose
line of totality goes through Land's End, Paris, and Munich.)
-- 
:-  Michael A. Covington     internet mcovingt@uga.cc.uga.edu :   Verbum caro
:-  Artificial Intelligence Programs       phone 706 542-0358 :    factum est
:-  The University of Georgia                fax 706 542-0349 :  et habitavit
:-  Athens, Georgia 30602-7415 U.S.A.     amateur radio N4TMI :   in nobis...
Newsgroups: sci.astro
From: rkornilo@nyx.cs.du.edu (Ryan Korniloff)
Subject: Re: Voyager UVS shutdown
Organization: University of Denver, Dept. of Math & Comp. Sci.
Date: Sun, 20 Dec 92 06:14:37 GMT

Yeah, that really is a shame. But let me ask this.. Does this mean that
Voyager has discontinued to look for the helopause? Or does this mean that
only one of the instuments have been shutdown, and there are still others
that are active..


        -- Ryan Korniloff
        -- rkornilo@nyx.cs.du.edu

Newsgroups: sci.astro
From: rlm@sunlight.Physics.UIowa.Edu (Robert Mutel)
Subject: New Meade Refractors and LX-200
Organization: Department of Physics and Astronomy, University of Iowa
Date: Mon, 14 Dec 1992 21:13:44 GMT

We are considering replacing our Celestron C-8 with another similar aperture
instrument with superior optics . Our experience with Schmitt-Cass telescopes
have been less than satisfactory with CCDs, especially with respect to image
quality, vignetting, and coma. It also needs to be refocussed with filter
changes (achromaticity). On the other hand, we have a 300mm f/2.8 Canon
telephoto lens with excellent optics which works very well with mininal optical
defects.

Has anyone on the net much experience with the new Meade refractors? We are
interested in simply the optical tube assembly, not the complete system. We
are
thinking about either the 6 or 7 inch models. Any comments on optical quality?

For another application we are considering the 10 inch LX200 system. Has anyone
carefully measured the drive characteristics? [e.g. pointing accuracy,
repeatibility, tracking accuracy]. Also, any comments on the optical
quality?

Thanks, 
-- 
Robert Mutel
From: ucap22a@ucl.ac.uk (Mr Alisdair R Davey)
Newsgroups: sci.astro
Subject: Re: Lunar Eclipse not visible in Holland
Date: 11 Dec 92 19:05:01 GMT
Organization: Bloomsbury Computing Consortium, London

Fickle this cloud stuff...I had the good fortune to be at University of
London observatory wednesday evening (Mill Hill, N. London). It cleared
for us at about 20:30 and stayed perfectly clear until about 5 minutes 
after the last contact. The concensus of opinion was that eclipse was
dark ! Dark brown -> dark orange covers the colour range. We had a myriad 
of telescopes pointed at the eclipse from 10 inch meades to the 24 inch
Allen telscope which was doing spectroscopy. We have a fairly good
set of crater timings and photographs etc. An excellent time was had by all.
I have the good fortune to demonstrate at the observatory twice a week,
its not such good fortune for the students cos I tend to spend as much time
as I can looking through the telsecopes rather than letting the students.
Well they don't really appreciate what they are looking at :-)....
A few weeks ago I was very glad of the standard red safety tape everyone
has to be taken through. I had the 18" radcliffe refractor all to myself
for 30 minutes to look at Swift-tuttle...definately one of the perks of the
job !

Alisdair
Newsgroups: sci.astro
From: andromed@cs.dal.ca (Mike Boschat)
Subject: Greetings
Organization: Math, Stats & CS, Dalhousie University, Halifax, NS, Canada
Date: Sun, 20 Dec 1992 15:00:08 GMT


 Hello fellow astronomers/scientists just a short note;


               MERRY XMAS  &  HAPPY NEW YEAR 1993 !!!!


 may we see many astronomical events in 1993......


  

						Clear skies

						Mike Boschat

                                          andromed@sleet.atm.dal.ca
 ---------------------------------------------------------------------------
|                                   |  "Our problems are man-made,          |
|        JOHN F. KENNEDY            | therefore they can be solved by man " |
|                                   |                                       |
|   ASTRONOMICAL  OBSERVATORY       |                 J.F.K.                |
|                                   |                                       |
 ---------------------------------------------------------------------------                                                                     
          
            
            
            
            





  
                
Newsgroups: sci.astro
From: phfrom@nyx.uni-konstanz.de (Hartmut Frommert)
Subject: Re: Hubble constant
Organization: Dept. of Physics, University of Constance
Date: Wed, 16 Dec 1992 09:10:06 GMT

train@ccwf.cc.utexas.edu writes:

>donald.mcintyre@almac.co.uk (Donald Mcintyre) writes:
>>
>>>I heard recently that there was new evidence just published somewhere
>>>pinning the Hubble constant to about 60 km/sec/megaparsecs. Can anyone
>>>comment on how this relates to estimates on the time from the Big
>>>Bang?
>>
>The age of the universe is:

>          t_universe = 1/H

That is in standard cosmology the upper bound of the age of the universe.

With a cosmological constant, also that statement is no longer true, all
you can say then is that the age of the universe is of the order of 1/H.
--
 Hartmut Frommert                 <phfrom@nyx.uni-konstanz.de>
 Dept of Physics, Univ of Constance, P.O.Box 55 60, D-W-7750 Konstanz, Germany
                                           -- Eat whale killers, not whales --
Newsgroups: sci.astro
From: mario@cs.man.ac.uk (Mario Wolczko)
Newsgroups: sci.astro
Subject: info sought on Lick observatory "amateur" night
Date: 19 Dec 92 16:27:06 GMT
Organization: Dept Computer Science, University of Manchester, U.K.


  A couple of years ago I had the opportunity to take the "tour" of
  the Lick 36" refractor on Mount Hamilton.  Unfortunately, I was
  unable to be there on a Friday night; I was told the 36" was open to
  amateurs on Fridays.  Is that still true?  I may get another
  opportunity in mid-January.  Has anybody been up there on an open
  night?  Do you get a brief look at some bright object chosen for you
  or an extended view of something more challenging, perhaps of your
  own choosing?  Did you need to book in advance? 

  More practically, is the road likely to be open in January, or
  snowbound?  The drive up was splendid on a sunny September afternoon
  -- I imagine a midwinter night is more challenging!

Thanks
Mario Wolczko

   ______      Dept. of Computer Science   Internet:      mario@cs.man.ac.uk
 /~      ~\    The University              uucp:    mcsun!uknet!man.cs!mario
(    __    )   Manchester M13 9PL          JANET:         mario@uk.ac.man.cs
 `-':  :`-'    U.K.                        Tel: +44-61-275 6146  (FAX: 6236)
____;  ;_____________the mushroom project___________________________________
From: K3032E0@ALIJKU11.BITNET (Herbert Raab)
Newsgroups: sci.astro
Subject: Rediscovery of P/Swift-Tuttle
Date: 19 Dec 92 05:40:50 GMT
Organization: Johannes Kepler University Linz - Computing Center

I was quite surprised that "P/Swift-Tuttle" was rediscovered by an amateur-
astronomer using "ordinary" binoculars. As far as I know, lots of professional
and serious amateur astronomers searches for this object, using large Schmidt-
cameras or high-tech-CCD-equipment. The comet was not THAT far off the
predicted path (17 day late, and the orbit was said to be uncertain by
roughly 2 months) and bright enough to be spotted visually.

I even know of no pre-discovery observations published so far in the IAU-
Circulars or the last batch of MPC's.
So, what happend?

By the way: As far as I am concerned, the "real" discoverer is B.G.Marsden,
who did the astonishing calculations on the comets orbit.
GREAT work|||

 Keep on watching'
 (and calculating, of course)

     Herbert Raab  >>>K3032E0@EDVZ.Uni-Linz.Ac.AT<<<
Newsgroups: sci.astro
From: lowry@src.honeywell.com (Dave Lowry)
Subject: Re: Subject: Newport Glass horror story (long) (was Re: ATM Materials)
Organization: Honeywell Systems & Research Center
Distribution: na
Date: Mon, 14 Dec 1992 16:54:32 GMT

> curtjb@halcyon.com (Curt Brown) writes:
>>combs@vaxr.llnl.gov writes:
>
>>A word of warning about Newport Glass -  I ordered some supplies from them
>>COD.
>>
>         < *** details of a horrible six-month ordeal removed *** >
>
>I sure wish I'd been able to read this post before I ordered from Newport.  A
...
>stock.  Sorry for the long post... Deal with this outfit at your own risk.

Ditto.  After numerous long distance calls and broken promises to call
me back, I simply gave up.  Fortunately, my credit card was never charged.
Newsgroups: sci.astro
From: neely@iowasp.physics.uiowa.edu
Subject: Daytime naked eye planet viewing
Organization: Department of Physics and Astronomy, University of Iowa
Date: Mon, 14 Dec 1992 20:57:07 GMT


I guess I wasn't clear in my last posting about seeing the
Sun, Venus, Jupiter and then the moon.  I saw all of these with
the naked eye and I did NOT need a telescope to view them.

When I saw this sight, I called over some other people to see if they
could see it too, and everybody the I pointed it out to could see
the two planets and our moon and sun.  I have never since seen
anything like it, although it is easy to find Venus during the
daytime if you know where it is.  With modern ephemeris programs
on personal computers, you should be able to get the altitude and
azimuth of Venus for a specific date and time and then then the
wheather is good, go out and find it.  I have seen Venus many times
from Iowa City, Iowa which is about 700 ft elevation above sea level
so people at higher elevations should be able to see Venus also.

Venus doesn't have to be at maximum brightness to see it naked
eye in the daytime, either, although it helps if it is.

Clear Skies

			-Matt Neely

Newsgroups: sci.astro,rec.radio.shortwave
From: oler@rho.uleth.ca (Cary Oler)
Subject: Daily Solar Geophysical Data Broadcast for 17 December
Organization: University of Lethbridge
Date: 18 Dec 92 10:01:29 GMT

!!BEGIN!! (1.0) S.T.D. Solar Geophysical Data Broadcast for DAY 352, 12/17/92
10.7 FLUX=150.3  90-AVG=136        SSN=157      BKI=0133 3542  BAI=016
BGND-XRAY=B6.2     FLU1=8.4E+05  FLU10=9.9E+03  PKI=0033 4543  PAI=017
  BOU-DEV=003,005,026,021,028,087,056,013   DEV-AVG=029 NT     SWF=00:000
 XRAY-MAX= C7.0   @ 1132UT    XRAY-MIN= B5.7   @ 1040UT   XRAY-AVG= B7.5
NEUTN-MAX= +004%  @ 1610UT   NEUTN-MIN= -002%  @ 2320UT  NEUTN-AVG= +0.4%
  PCA-MAX= +0.1DB @ 2000UT     PCA-MIN= -0.3DB @ 1245UT    PCA-AVG= -0.0DB
BOUTF-MAX=55428NT @ 1531UT   BOUTF-MIN=55379NT @ 1952UT  BOUTF-AVG=55411NT
GOES7-MAX=P:+159NT@ 1855UT   GOES7-MIN=E:-020NT@ 1809UT  G7-AVG=+077,+020,+012
GOES6-MAX=P:+179NT@ 1857UT   GOES6-MIN=E:-028NT@ 0811UT  G6-AVG=+096,-007,+027
 FLUXFCST=STD:145,140,135;SESC:145,140,135 BAI/PAI-FCST=020,020,015/020,025,015
    KFCST=3443 3334 3454 3344  27DAY-AP=004,008   27DAY-KP=1101 1112 4320 0011
 WARNINGS=*SWF
   ALERTS=**MAGSI:19NT@0615UTC;**MAGPAUSE:GOES-6@1745-1746UTC
!!END-DATA!!
From: Gregg.Pasterick@f118.n109.z1.fidonet.org (Gregg Pasterick)
Sender: Uucp@blkcat.UUCP
Newsgroups: sci.astro
Subject: Geminid Data
Date: Mon, 14 Dec 1992 15:34:56 -0500

I am interested in any observational data of the Geminid Meteor Shower 
for a newsletter and slowly growing data base.  Anyone interested in 
sharing data, please respond to this message.
Gregg Pasterick

Newsgroups: sci.astro,rec.radio.shortwave
From: oler@rho.uleth.ca (Cary Oler)
Subject: Daily Solar Geophysical Data Broadcast for 15 December
Organization: University of Lethbridge
Date: 16 Dec 92 09:04:42 GMT

!!BEGIN!! (1.0) S.T.D. Solar Geophysical Data Broadcast for DAY 350, 12/15/92
10.7 FLUX=155.5  90-AVG=135        SSN=179      BKI=3223 2223  BAI=010
BGND-XRAY=B5.5     FLU1=6.8E+05  FLU10=1.1E+04  PKI=3213 2223  PAI=009
  BOU-DEV=022,012,012,022,016,013,015,020   DEV-AVG=016 NT     SWF=00:000
 XRAY-MAX= C6.9   @ 0113UT    XRAY-MIN= B4.7   @ 2005UT   XRAY-AVG= B8.7
NEUTN-MAX= +003%  @ 2110UT   NEUTN-MIN= -002%  @ 0600UT  NEUTN-AVG= +0.4%
  PCA-MAX= +0.1DB @ 2350UT     PCA-MIN= -0.3DB @ 1335UT    PCA-AVG= -0.0DB
BOUTF-MAX=55425NT @ 0456UT   BOUTF-MIN=55398NT @ 2114UT  BOUTF-AVG=55416NT
GOES7-MAX=P:+115NT@ 1744UT   GOES7-MIN=N:+002NT@ 0307UT  G7-AVG=+074,+025,+010
GOES6-MAX=P:+134NT@ 1745UT   GOES6-MIN=E:-022NT@ 0733UT  G6-AVG=+093,-006,+031
 FLUXFCST=STD:155,155,150;SESC:155,155,150 BAI/PAI-FCST=007,007,010/010,010,012
    KFCST=2223 3222 2223 3222  27DAY-AP=005,006   27DAY-KP=2111 3221 1212 3211
 WARNINGS=*SWF
   ALERTS=**245STRM:0000-2359UTC
!!END-DATA!!
From: bweiner@ruhets.rutgers.edu (Benjamin Weiner)
Newsgroups: sci.astro
Subject: Re: The Hole Story
Date: 14 Dec 92 00:27:17 GMT
Organization: Rutgers Univ., New Brunswick, N.J.

chris@chrism.demon.co.uk (Chris Marriott) writes:
>Wouldn't communicate be (at least theoretically) possible using Hawking
>radiation - ie, high-energy photons annahilating to an electron/positron
>pair, one inside and one outside the event horizon?  

Anything involving Hawking radiation should be taken with a large grain
of salt, since it's an intrinsically semiclassical calculation.  But the
heuristic picture of it is particle-antiparticle pairs created outside
the horizon, where one falls in and the other escapes.  So if you had
photons outside the horizon creating e+e- pairs, the e+ or e- could
escape - but the photons had to start outside to begin with.

> If you had, say, a
>strong gamma-ray source with you inside the event horizon, wouldn't this
>result in a flux of electrons and/or positrons *outside* the event horizon?

No.  At least not within the framework of Hawking radiation.
From: buffet@gandalf.inria.fr (Georges Buffet)
Newsgroups: sci.astro
Subject: Universal time
Date: 10 Dec 92 14:01:31 GMT
Organization: INRIA, Sophia-Antipolis (Fr)

does it exist somewhere on the net a universal time server,
and if yes, how to use it ?
We do not need high precision. (10 -e02 second will be enough)

thanks in advance

-- 
Georges Buffet:                            |
  Chercheur CNRS, Institut de Geodynamique | phone (33) 93 95 42 60
  Avenue Albert Einstein   Sophia-Antipolis|
  06565 Valbonne Cedex -- FRANCE           |
                ou
  Projet PASTIS,  INRIA - Sophia Antipolis,| e_mail:buffet@parsifal.inria.fr
         2004, route des Lucioles,         |  phone: (33) 93 65 78 54
         06565 Valbonne Cedex -- FRANCE    |    Fax: (33) 93 65 77 43
From: jsmill01@ulkyvx.louisville.edu
Newsgroups: sci.astro
Subject: Re: Earth's Orbit if no other planets
Date: 16 Dec 92 17:27:04 GMT
Organization: University of Louisville

In article <7460061@hpfcso.FC.HP.COM>, duanej@hpfcso.FC.HP.COM (Duane Jacobson) writes:

[stuff deleted]

> 
> In fact, this is how the existence of Pluto was discovered.  Neptune's
> orbit was perturbed in a way that could most easily be explained by the
> existence of a small planet in a nearby orbit.  So they looked for it and
> found it.

I don't think so.  I believe that the scenario was more like Uranus 
had perturbations in its orbit that still could not be explained by 
just the presence of Neptune.  Having success with finding Neptune, 
the same method was tried again, this time in vain.  Pluto was found 
after a long photographic search along the ecliptic.  And if recent 
finding are valid, the perturbations ascribed to Uranus may not really 
have been as large as had been thought, which means, given its mass, 
finding Pluto was more a fluke, albeit on that yielded an interesting 
find.

Scott Miller, Program Coordinator
Rauch Memorial Planetarium
University of Louisville
jsmill01@ulkyvx.louisville.edu