HDTenEightyP/NetNews huggingface dataset:
From: zellner@stsci.edu
Subject: Re: Moon illusion
Organization: Space Telescope Science Institute
Distribution: na
Date: Thu, 19 Nov 1992 14:35:11 GMT


>> ..........   When the moon appears near the horizon
>> its light must traverse a greater amount of earths atmosphere.  The
>> light rays are bent more and thus the atmosphere actually acts like
>> a magnifying lense ....
> 
> Nope.  Sorry.  It's just an illusion.  

Somebody told me that other primates (chimpanzees, etc.) seem to see the 
same illusion.  Something about the way our brains are wired.

> When the moon is on the horizon,
> your brain puts it in relation to the things that are in the line of sight,
> like trees and buildings and it looks big against them.  When the moon is
> overhead, there are no such things and it "looks" smaller.  

Actually I think it must be a little more than that.  In nature we seldom
see things vertically (trees, birds, etc.) more than a few hundred feet 
high.  But on the horizon we can see things (mountains, etc.) that are miles 
away.  Thus when we see a half-degree object overhead, our brains think it's 
close by and hence "small" in actual size.  But when we see it on the horizon, 
we think, "Gosh, that's way off on the horizon, and it still looks that big!  
It must actually be enormous!"

For the same reason the sky doesn't look hemispherical to our perceptions, 
it looks rather bowl-shaped.  Things never look quite right inside a hemi-
spherical planetarium dome.

Ben

Newsgroups: sci.astro
From: palmer@sfu.ca (Leigh Palmer)
Subject: Re: Distance of horizon
Organization: Simon Fraser University
Date: Thu, 19 Nov 1992 02:14:30 GMT

In article <lglhj3INNb0c@appserv.Eng.Sun.COM> fiddler@concertina.Eng.Sun.COM
(steve hix) writes:
>Anyone have handy a function for figuring the distance of the
>horizon from a viewer based on the viewer's height from the
>surface?
                            -1
Try d = R arccos ( 1 + h/R )

    d = horizon distance
    h = height above MSL (assuming horizon is at sea level)
    R = radius of Earth

I tried to find a series expansion for arccos ( 1 + z ) in my tables, but there
ain't one there. I think I see how to figure one out, but I've got to go home
now.

>This has to do with amusing my kids a bit during our next
>science discussion.  Dad's got to stay ahead *some* way... :}

I'm tickled to be able to say I know exactly what you mean. Ain't that a great
problem to have?

Leigh
From: foltz@as.arizona.edu (Craig B. Foltz)
Newsgroups: sci.astro
Subject: Re: Gravitational lenses
Date: 20 Nov 92 13:14:50 GMT
Reply-To: foltz@as.arizona.edu
Organization: MMT Observatory, Univ.of Arizona

In article GILMART@LSTC2VM.stortek.com, GILMART@LSTC2VM.stortek.com (Paul Gilmartin) writes:
>In article <Vm4FuB3w165w@west.darkside.com>
>max@west.darkside.com (Erik Max Francis) writes:
> 
>>millnerrl@vtcc1.cc.vt.edu (CALLABLE_TPU) writes:
>>> an odd stellar object called I believe "The Einstein Cross" that was explaine
>>
>>I've never heard of the Einstein Cross, but I _do_ know of the Einstein
>>Ring.
> 
>The name I vaguely recall is "Huachra's (sp.? Huchra's?) Cross."  Maybe
>you can find it in an index by that name.
>>
There are two objects which fit this description.  The first is 2237+03, which
shows four images of the same object separated by a few arcsec.  This was discovered
by Huchra et al as part of the CfA Redshift Survey.  The 'Einstein Cross' is the 
well-known BAL (broad absorption line) QSO 1413+113, which was shown to have four
images arranged in a cross, with maximum separation of about 1.2 arcsec (I'm
woking from memory here).  I believe that both have been imaged with HST.

---
Craig Foltz                               cfoltz@as.arizona.edu
Multiple Mirror Telescope Observatory     Tel   (602) 621-1269
Univ. of Arizona, Tucson, AZ 85721        Fax   (602) 670-5740
     "Help me!  I've fallen and I can't reach my mouse!"
Xref: sparky sci.astro:12149 sci.classics:1016
From: mcdowell@head-cfa.harvard.edu (Jonathan McDowell)
Newsgroups: sci.astro,sci.classics
Subject: Re: Know an adjective for black holes?
Date: 18 Nov 92 15:21:16 GMT
Organization: Smithsonian Astrophysical Observatory, Cambridge, MA,  USA

From article <BxvC4z.Mq9@javelin.sim.es.com>, by biesel@javelin.sim.es.com (Heiner Biesel):
[... what's a good adjective for black hole?]

In a paper in MNRAS (I think by Martin Rees about 15 years ago but 
I can't remember the reference) the analog to 'perigee', 'perihelion',
etc. was suggested as 'peribothron' on the grounds that 'Bothros'
was the name of a sort of Ancient Greek 'Black Hole of Calcutta'
and came to mean 'a deep dark pit that you never get out of'.
[I'm trying to cross-post this to sci.classics in case someone there
can tell me whether this is true.]
So perhaps 'bothronic' whould be a good adjective? I liked 'singular',
as suggested by one poster, but it applies to other objects 
(like the Big Bang and some kinds of cosmological topological
defects) so we need something more specific to BH's. 



 .-----------------------------------------------------------------------------.
 |  Jonathan McDowell                 |  phone : (617) 495-7176                |
 |  Harvard-Smithsonian Center for    |                                        |
 |   Astrophysics                     |                                        |
 |  60 Garden St, MS4                 |                                        |
 |  Cambridge MA 02138                |  inter : mcdowell@urania.harvard.edu   |
 |  USA                               |  inter : mcdowell@cfa.harvard.edu      |
 '-----------------------------------------------------------------------------'

   
Newsgroups: sci.astro,su.market,ba.market,ca.forsale,misc.forsale
From: wmesard@cs.stanford.edu (Wayne Mesard)
Subject: FOR SALE: Celestron 8 Telescope
Organization: Distributed Systems Group, Stanford University
Distribution: na
Date: 23 Nov 92 11:14:50

Jus' the facts:

	Features:
	 o  electric clock drive
	 o  2000mm focal length

	Includes:
	 o  tripod
	 o  equatorial wedge
	 o  solar filter
	 o  three eyepieces: 40mm, 25mm and 12mm
	 o  locking storage / transport case

	Asking Price: $750 + any shipping

	For more information contact Wayne Mesard:
	 o  phone: 415/367-7890
	 o  email: WMesard@cs.Stanford.edu

	``The perfect Christmas gift''(tm)
	It can be seen in Redwood City, California (at no obligation).
	Owner's manual can be seen in RWC or at Stanford.

Some more details:

	Model:	Classic 8 (with the orange casing).
	Optics: Magnesium flouride coating.
	Tripod:	Aluminum.
	Finder:	6x - 30mm.
	Drive:	110vAC, 6 watts.
	Age:	It was given to me (new) 12 years ago.  I used it a few dozen
		times when I first got it, rarely since then.  But I just
		checked the optics and stuff and everything's still clean,
		aligned and working swimmingly.

--
Wayne();
WMesard@cs.Stanford.edu
From: jack@cs.com (Jack Hudler)
Newsgroups: sci.astro
Subject: Re: Distance of horizon
Date: 20 Nov 92 13:14:37 GMT
Organization: Computer Support Corporation,  Dallas,Texas

In article <75439@hydra.gatech.EDU> collins@emperor.gatech.edu (Tom Collins) writes:
>In article <1992Nov19.021430.13833@sfu.ca> palmer@sfu.ca (Leigh Palmer) writes:
>>In article <lglhj3INNb0c@appserv.Eng.Sun.COM> fiddler@concertina.Eng.Sun.COM
>>(steve hix) writes:
>>>Anyone have handy a function for figuring the distance of the
>>>horizon from a viewer based on the viewer's height from the
>>>surface?
>>                            -1
>>Try d = R arccos ( 1 + h/R )
>>
>>    d = horizon distance
>>    h = height above MSL (assuming horizon is at sea level)
>>    R = radius of Earth
>
>       2    2        2
>since R  + d  = (R+h)         (Pythagorean theorem)
>
>                2    2
>d = sqrt(  (R+h)  - R  )
>
>This says that the horizon for a six-foot tall person is about
>3 miles away.

But these equations would give the 'mean' horizion, shouldn't you include
refraction to give the 'apparent' horizion?
-- 
Jack 		Computer Support Corporation		Dallas,Texas 
Hudler		Internet: jack@cs.com
Newsgroups: sci.astro,sci.physics
From: metares@well.sf.ca.us (Tom Van Flandern)
Subject: Gravity waves (Was: Galilean Electrodynamics)
Organization: Whole Earth 'Lectronic Link
Date: Thu, 19 Nov 1992 04:32:53 GMT


     In a reply to Mark Schlegel, gsh7w@fermi.clas.Virginia.EDU (Greg
Hennessy) wrote an especially fair review of the Galilean Electrodynamics
journal, given his differences of opinion with Beckmann.  But he does raise
one issue deserving of further comment:

> Beckmann has stated that his theory does not allow for gravational
> radiation from orbiting neutron stars, but the pulsar PSR 1913+16 is
> losing energy at the exact rate predicted by GR through gravational
> radiation, so for me, is a fatal flaw for Beckmann's theory.

     It would be nice if we could get this question of what the binary
pulsars do and don't show straightened out.  There is no doubt that Taylor
and Damour left the impression in their early papers that the existence of
gravitational radiation had been verified.  But they have been sharply
criticized for this, and their current story is a rather more modest claim.
They now seem to maintain that the orbits of PSR 1913+16 and 1534+12 are
consistent with GR + gravity waves, thereby providing a verification of
sorts.  Moreover, the orbits are inconsistent with many variations of GR.
That's valuable to know.

     But the gravity wave term is not uniquely separable from other
parameters in the solutions (namely, periastron motion and the bending/delay
term).  [See Taylor, J.H., Wolszczan, A., Damour, T., and Weisberg, J.M.,
"Experimental constraints on strong-field relativistic gravity," Nature 355,
132-136 (1992); and Damour, T., "General relativity and experiment: a brief
overview," Class.Quantum Grav. 9, 55-59 (1992).]  This means that GR without
any gravity waves and certain other theories can still be made to fit the
pulsar data equally well by adjusting the masses and elements until the
periastron rotates a bit faster and takes up what appeared like a small
acceleration in the original solution.

     As if this were not reason enough to adopt a wait-and-see stance about
gravity waves, there are now reasons to doubt the theoretical model for
gravitational radiation used by Taylor and Damour in their solutions.  See
the new paper: Yu Xin (A. Yu), "Does Einstein's G.R. theory predict
gravitational radiation of PSR 1913+16?", Astrophys.&SpaceSci. 194, 159-163
(1992).  This author concludes that "the Einstein approximation scheme gives
no gravitational radiation.  ...  The claim that observed data from PSR
1913+16 has verified Einstein's gravitational radiation theory is, therefore,
groundless."

     I realize that Greg was quoting conventional wisdom.  Is it time to
alter the conventional wisdom about gravity waves and binary pulsars?
     -|Tom|-

-- 
Tom Van Flandern / Washington, DC / metares@well.sf.ca.us
Meta Research was founded to foster research into ideas not otherwise
supported because they conflict with mainstream theories in Astronomy.
Newsgroups: sci.astro
From: heiser@fretz.enet.dec.com (Michael A. Heiser)
Subject: Re: Astronomy jpg files posted.
Reply-To: heiser@fretz.enet.dec.com (Michael A. Heiser)
Organization: Digital Equipment Corporation - Phoenix, AZ
Date: Mon, 16 Nov 1992 19:05:44 GMT


Thanks for posting these!  
--

    Mike
    
    "in this day & age...music performed by humans...hum?!" 
       - wilde silas tomkyn
From: evm@opo.vanc.wa.us
Newsgroups: sci.astro
Subject: Re: PK118+2.1 was SAC database
Date: 17 Nov 92 06:46:44 GMT
Article-I.D.: opo.1992Nov16.224644.26
Organization: OuterPlane Observatory, Vancouver, Wa

In article <1992Nov13.170449.6401@linus.mitre.org>, chaloux@mandolin.mitre.org (Dave Chaloux) writes:
...
> 
> Now my question.
> 
> It has an entry for PK118+2.1 at 00 07.3, + 64 58 15. It lists this as
> having the alternate designation Sh 1-118. It is 12.9 Mag and 120" in
> size. This is exactly the kind of object I would like to hunt down.
> Unfortunately, it gives the constellation as CAM and any quick check
> of a star atlas will tell you that is the wrong constellation for the
> coordinates. (CAS is correct). I checked my Uranometria at those coordinates
> and it is not plotted there. I also checked at 07 hours which would be in
> CAM and it wasn't there either.
> 
> Could someone with the appropriate references look this up and let me
> know what the story on this guy is. I am hoping CAM should be CAS and that
> Uranometria simply didn't plot it.
> 
> Thanks in advance and Clear Skies (and I think I might actually have them
> tonight. Its been awhile here.)
-- 

	I have a first edition of Uranometria that has PK118+2.1 plotted just 
at the coordinates you gave. It is on chart 15. I did a little more looking in 
my modest personal library and found that PK118+2.1 is listed  misclassified
as a planetary nebula so has been removed from the PK. Could this be why it is
not plotted in your (later) Uranometria?

	Of interest is the plate on page 11 (NGC 7762 and 7822 field) in Hans
Vehrenberg's Atlas of Deep-Sky Splendors. Using a 36cm schmidt camera for this
field he captured PK118+2.1 with ease. He was unaware of the designation of
this nebula but noted it in the text. It looks a lot like IC5146 does so I
wonder if they are like objects. It looks to 15' in diameter from the plate.

	Being well situated for observation this fall let me know if you are
able to see it and with what instrument. I'll try for it when we get some
clear weather here in the wet NW. CAS rides high from darkfall on.

Please post any further information on this object!

	Regards, Ethan

........        ........        ........
OPO Observatory
17104 ne 35th Cir	Ethan VanMatre          
Vancouver, Wa 98682	evm@opo.vanc.wa.us
Newsgroups: sci.astro
From: zrepachol@cc.curtin.edu.au
Subject: Cost of telescope time... was he-men....
Organization: Curtin University of Technology
Date: Tue, 17 Nov 1992 11:49:23 GMT

In article <1992Nov12.181116.2860@athena.mit.edu>, hbh@athena.mit.edu (Heidi Hammel) writes:
...
> astronomer -- is the cost of telescope time for large facilities.  At
> thousands of $$$ per night of taxpayer money (in the case of the NASA
> IRTF, for example), it only makes sense to make the best use of the
> time, and a warm astronomer can function more effectively and efficiently
> than a freezing astronomer.   IMHO, of course.
> 

Hum, I have long wondered about this 'cost', so I will now ask.
How much would 12 hrs of IRTF cost? What would the cost be if everone stayed
home for the night?

~Paul
From: thfore@vader.cc.emory.edu
Newsgroups: sci.astro
Subject: Coputers and the Hubble
Date: 18 Nov 1992 17:34:15 -0600
Organization: UTexas Mail-to-News Gateway
NNTP-Posting-Host: cs.utexas.edu

The article about the Hubble in a recent issue of Sky and Telescope  
never got technical about the computers used at the Space Telescope  
Science Institute to drive HST ( such as image processing and  
enhancement, etc). Does anyone know about this?

And now on a much , much lighter note.......
a friend of mine wants to know if the tech. assistant from STScI that  
was pictured in the article (Keith Noll) is married, engaged or  
otherwise attached. Anyone know him?


---------------------------------------------------------------------
Howard Fore                                 thfore@vader.cc.emory.edu
"At Apple, Quality is job 1.1.1!" - anonymous Apple systems engineer
From: qsi@contrast.wlink.nl (Peter Kocourek)
Newsgroups: sci.astro
Subject: Re: NASA Duplicity?
Date: Sat, 21 Nov 1992 01:42:52

In a message of <19 Nov 92  19:40:00>, SCOTT I CHASE writes:

 > From: sichase@csa1.lbl.gov (SCOTT I CHASE)
 > 
 > To clarify a bit:
 > 
 > There is quite a difference between choosing an appropriate vertical
 > scale to display your data (which is what NASA and the rest of the
 > world does) and changing the facts, which I think is what the poster
 > was worried about.  NASA has never quoted a height that is 25 times
 > larger than the actual measured height of a Venusian feature in order
 > to make the evening news. 

Exactly. It all started with a message, along the lines of "How can we ever
again trust NASA if they tell all these lies?" I thought it'd be better to
check the facts with the folks who know more about it than I do. :-) Anyway,
I've had also a number replies by e-mail, and I'll summarize in a few days'
time.

YHS:QSI!

Newsgroups: sci.astro
From: cflatter@nrao.edu (Chris Flatters)
Subject: Re: st6 images wanted
Reply-To: cflatter@nrao.edu
Organization: NRAO
Date: Thu, 19 Nov 1992 22:53:16 GMT

In article 6479@organpipe.uug.arizona.edu, newberry@kepler.as.arizona.edu (Mike Newberry) writes:
>Skip the first 2880 bytes of the file, as this contains the file information
>"header" in FITS format. Starting at byte offset 2880 will be found binary,
>uncompressed, unpadded pixel data. The pixels are unsigned 16-bit integers,
                                                   ^^^^^^^^^^^^^^^^^^^^^^^^
>so watch out if unsigned integers might choke your software--these images do
>have values above 32767. To turn this binary raster file into a 2-dimensional
>image, note that there are 375 2-byte pixels in each row. There are 242 rows.

If this description is accurate the files do not conform to accepted FITS
standards.  Either 16-bit integers are twos complement or SIMPLE = F.

	Chris Flatters
	cflatter@nrao.edu


Newsgroups: sci.astro
From: mike@elec.canterbury.ac.nz (Cosmik Debris)
Subject: Re: Know an adjective for black holes?
Organization: Electrical Engineering, University of Canterbury, New Zealand
Date: Mon, 16 Nov 1992 01:16:40 GMT

In article <13NOV199219034877@erich.triumf.ca>, asnd@erich.triumf.ca (Donald Arseneau) writes:
> In article <SRCTRAN.92Nov11233822@world.std.com>, srctran@world.std.com (Gregory Aharonian) writes...
> % >   To refer to the Earth, I can use  "terrestrial".
> % >   To refer to the stars, I can use  "stellar".
> % >   To refer to galaxies,  I can use  "galactic".
> % >   To refer to black holes,  what can I use?
> 
> Singular!
holier than thou.
-- 
Cosmik Debris -- "I owe money, therefor I am"
From: jack@cs.com (Jack Hudler)
Newsgroups: sci.astro
Subject: Re: Planetarium
Date: 21 Nov 92 15:42:43 GMT
Organization: Computer Support Corporation,  Dallas,Texas

In article <1992Nov20.133557.1947@ccsvax.sfasu.edu> z_johnsta@ccsvax.sfasu.edu writes:
>     I work in the planetarium here at SFA, and I was wondering if anyone had
>ever used the A-Bus from Alpha Micro (or Alpha-something, I don't remember
>what...) to control slide projectors in a planetarium or similar environment. I
>know the thing has several types of D-A converter cards, Relay cards, and
>Stepper Motor controller cards, so it should't be hard to do.  I am interested
>in any experiences any of you have had with the A-Bus in particular, but I am
>also open to suggestions regarding other products as well. 

ALpha Products A-BUS line is a pretty simple setup, even when you get into
the stepper motor stuff. Its simple to program for and even simpler to 
repair the boards, with not very many chips present on most boards you can
easly diagnose which chip failed.
And its perfect for your project and a planetarium budget, just make
sure they know that you are going to add Software Engineer to your 
title and the time that goes with it.

-- 
Jack 		Lone Star Observatory			Dallas,Texas 
Hudler		Internet: jack@cs.com
Newsgroups: sci.astro,sci.space
From: wa2ise@cbnewsb.cb.att.com (robert.f.casey)
Subject: Re: Hubble's mirror
Organization: AT&T
Date: Wed, 18 Nov 1992 04:20:21 GMT

In article <18865@ksr.com> jfw@ksr.com (John F. Woods) writes:
>All the managers who approved ignoring those tests (who were probably rewarded
>with bonuses for bringing the mirror in on-time) ought to be billed the repair
>costs.  (and whoever thought to add random spacing washers to a piece of
>*precision* equipment, instead of asking why it didn't fit like it was supposed
>to, ...

Whoever did the above adding washers to the test jig probably felt a lot of
time pressure from management to get it done NOW! and don't waste time
about it.  He also probably figured the designer made an error overlooking
a small mounting detail, and he could "correct" it easy enough with the
washers, and deliver it as done.  And his boss won't be on his ass.
Hell, in my job, I have to deal with a lot of bad documentation, missing
info, lack of proper training, time pressure, bad bosses, not enough time,
and other problems (excuses my boss calles them).  Odds are, given time
pressure and bad management, I might have hacked the above mirror tester
to get it done myself.  And probably I would have figured I had to make
the "correction" with the washers.  And not be able to ask the designer
about it ("he's in a meeting all day", "he's out of town", or some such,
or "can't you figure it out yourself, you idiot").
From: palmer@cco.caltech.edu (David M. Palmer)
Newsgroups: sci.astro
Subject: Re: Supernova (Was Re: P/Swift-Tuttle at last!)
Date: 20 Nov 1992 03:57:03 GMT
Organization: California Institute of Technology, Pasadena
NNTP-Posting-Host: alumni.caltech.edu

ins894r@aurora.cc.monash.edu.au (Aaron Wigley [Wigs]) writes:
> o The event happened in the region off-centre of the (from Memory, I may
>   be wrong) Large Magellenic Cloud. The Time was about 2115 local time,
>   (I cannot remember if Daylight saving time was in effect then - it would
>   depend on the date I will look up), on a Thursday night. Local time
>   is 10 hours ahead of UMT. 

The supernova went off Feb 23 1987, (by the time of the neutrino burst),
which was a Monday, and was discovered on the 24th, by Ian Shelton about
33 hours later.  If you read about it in the next day's paper, then you
probably saw it on Thurs Feb 26 1987.

-- 
		David Palmer		 palmer@alumni.caltech.edu
Newsgroups: sci.astro
From: beaucham@astro.phy.ulaval.ca (Dominique Beauchamp)
Subject: Re: Real Men Astronomers [Was Re: e-mail activated telescope?]
Followup-To: beaucham@phy.ulaval.ca
Organization: Universite Laval, Ste-Foy, Qc, Canada
Distribution: sci.astro
Date: Tue, 17 Nov 1992 15:35:27 GMT

In article <1992Nov11.151702.4566@midway.uchicago.edu> rfl@oddjob.uchicago.edu (Bob Loewenstein) writes:
>
>Of course, -30 to -35C (-35F) is not as bad as -75C (-100F) at
>mid-winter at the South Pole.

I agree!  

"South pole" observers and pinguins are real men!

Bye

Dominique Beauchamp
From: qsi@contrast.wlink.nl (Peter Kocourek)
Newsgroups: sci.astro
Subject: NASA Duplicity?
Date: 18 Nov 92 21:29:30 GMT

Hi,

 in a recent discussion on a bulletin board here, someone alleged that NASA
 cannot be trusted, because, as he said, it had deliberately deceived the
 public on a number of occasions. Personally, I am rather skeptical of his
 claims (no sources given), so I'd like more knowledgeable folks out here
 to comment on (and preferably, shoot down) these allegations.

 Firstly, it was alleged that NASA increased the size of a mountain on
 Venus (no name given) by a factor of 25, to make it more spectacular,
 and make the evening news.
 
 Secondly, NASA was alleged to have to have manipulated the results of
 surveys of the hole in the ozone layer, saying it was larger than its
 measurements showed.
 
 Thirdly, the well-known COBE graphic, that appeared in all newspapers,
 showing anisotropies in the cosmic background radiation, is alleged to
 have been only a graphic of test results, not of the actual measurements
 themselves.
 
 Am I dealing here with a professional NASA-basher, or is there any truth
 to the above allegations? All comments are welcomed, either as e-mail,
 or as replies in this newsgroup.
 
 Thank you.
 
 
 YHS:QSI!
Newsgroups: sci.astro
From: tholen@galileo.ifa.hawaii.edu (Dave Tholen)
Subject: Re: Okay, what are the new odds? (was Re: Swift_tuttle's orbit)
Organization: Institute for Astronomy, Hawaii
Date: Tue, 17 Nov 1992 04:04:49 GMT

Bill Higgins writes:

> Also, could you explain what your outgassing coefficients A1 and A2
> are to those of us who are not comet specialists?

Radial and tangential, respectively.  There's also an A3 which is normal
to the orbit plane.  Rarely solved for, but it's been done for P/Clark,
P/Swift-Gehrels, and Wilson (1986l), plus a few others for which more
recent orbit determinations have omitted it.

Then there's the old B1 and B2...