HDTenEightyP/NetNews huggingface dataset:
From: dpalmer@csulb.edu (David Palmer)
Newsgroups: sci.astro
Subject: Re: Comments from Meade about SCTs
Date: 21 Jan 93 16:56:50 GMT
Organization: Cal State Long Beach




In article <1993Jan20 221737 C16B9F.ADx@boi.hp.com> jmcvey@boi.hp.com  writes:

>I just called MEADE and talked with them about my 8" SCT.  Here
>are a few things I learned.  I welcome comments as to the validity
>of these things:

>1) It may take two hours for an SCT to reach thermal equilibrium.

Probably. What works for me is to set up outdoors in late afternoon, and
let the scope cool down with the day. I don't do anything critical
(like photography) until later in the night.

>2) You can do critical alignment by keeping the star in focus and
>   centering the airy disk within the diffraction ring pattern.

Do you mean alignment of the secondary mirror? And do you mean DEfocused?
If so, yes. In fact, that's the procedure listed in the Meade LX200 manual.

>3) A mask for the objective with two 2.5" holes on opposite sides
>   of the secondary will help achieve critical focus and will
>   demonstrate spherical aberation if you can't ever get the two
>   images to merge.

Yep, it works. There is a commercial product called, I think, Kwik-Focus,
which is advertised in _S&T_ and _Astronomy_ (*with* a photo of it, which
can be used as a guide to making your own ;-) ), but it's easier and cheaper
to make your own. I made one out of cardboard, and I stick it on with a wad 
of gaffer's tape on the secondary mirror cap. You could also make one out of 
a spare lens cap. Works just fine, though you need to use it on a fairly 
bright star, since it cuts out a lot of light. 
Also makes an adequate neutral density filter if you're observing a really 
bright Moon.



-- 
              Dave Palmer             dpalmer@csulb.edu

********************I finally found the perfect woman,*********************** 
*****************but she was looking for the perfect man*********************
Newsgroups: sci.astro
From: Leigh Palmer <palmer@sfu.ca>
Subject: Re: Toutatis Captured by Radar Images
X-Xxmessage-Id: <A786D033FF011C1D@rs14-annex3.sfu.ca>
X-Xxdate: Sat, 23 Jan 93 18:36:35 GMT
Organization: Simon Fraser University
X-Useragent: Nuntius v1.1.1d16
Date: Sat, 23 Jan 1993 18:36:36 GMT

In article <schumach.727766698@convex.convex.com> Richard A. Schumacher,
schumach@convex.com writes:
>>what it tells us about origins.  The rms velocity between any two
asteroids
>>is about 5 km/s -- somewhat more near the Earth's orbit.  Collisions
>>between such objects would be catastrophically destructive.  So the
joined
>>fragments must have been previously in orbit as satellites of the
asteroid,
>>brought down gradually by tidal forces until a gentle contact occurred.

This inadvertently unattributed quote is from Tom Van Flandern, of course.
I'm taking this slightly indirect means to pose a question regarding it.
Tom,
the 5 km/s rms two-particle velocity is indeed a nice number; I'd never
seen
it before. I'd like to know a little of the detail which went into the
calculation (a citation, perhaps, or will it be in the book?). In
particular, I'd like to know if the mean is for a sample of pairs of belt
asteroids taken at random, or of (potential) asteroid collisions. The
latter sample would 
have an additional selection effect enhancement by a factor of the
closing velocity. A higher rms relative velocity should obtain for the
latter sample than for the former.

>Mmmm, not necessarily. A small body striking a larger one might easily 
>disrupt the larger without dispersing the pieces. No doubt someone has
>already attempted to calculate a distribution of such collisions based
>on the known distribution of asteroid sizes and orbits.
>Remember that so far these contact binaries have been observed only at 
>low resolution. I'll predict that higher resolution images will show 
>most of them to consist of "rubble piles", that is, many pieces of 
>varied sizes, not just two big ones. (If so,
>they ought to named Barksian asteroids, after artist Carl Barks who first
>suggested the idea.) What does your theory predict? 

I also wanted to comment on this suggestion. Who needs an artist? Nature
herself has given us an exemplar - Miranda, the enigmatic inner satellite
of Uranus. These violent collisions may be said to "Mirandize" a minor
planet. (Since that neologism seems to have entered the lexicon already
from a different direction, such collisions could be confused with police
brutality.) 

>(By the way: is the exploded planet idea a consequence of your Meta
Theory?)

Mr. Schumacher, you are guilty of reification in the first degree.
Historical events cannot be consequences of subsequently propounded
theories. If logical convention did not prohibit it then violation of
causality would!
From: esj@harvee.billerica.ma.us (Eric S Johansson)
Newsgroups: sci.astro
Organization: gators 'r us
Subject: 1994 annular eclipse in USA
Summary: looking for path info
Reply-To: esj@harvee.billerica.ma.us
X-Software: HERMES GUS 1.10 Rev. Dec 23 1992
Date: Sun, 24 Jan 1993 21:00:22 -0400
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit

I am looking for path and timing information on the spring 1994 annular eclipse
that passes through the US.  Thanks in advance for any information.

--- eric
-- 
HOME: esj@harvee.billerica.ma.us  HAM  ka1eec
WORK: 617.630.4687 (w)   esj@ruby.polaroid.com
source of the public's fear of the unknown since 1956
Newsgroups: sci.astro
From: jbatka@desire.wright.edu
Newsgroups: sci.astro
Subject: Re: THE DIVINE MASTERS OF THE UNIVERSE
Date: 27 Jan 93 09:04:40 EST
Distribution: world
Organization:  Wright State University 

> In article <1993Jan25.173130.3296@cnsvax.uwec.edu>, mcelwre@cnsvax.uwec.edu writes:
>> Although the following article is on the subject of religious studies, it
>> illustrates some important facts about the Universe:
>>                                            Robert E. McElwaine
>>                                            2nd Initiate in Eckankar

The subject line reminds me of a cartoon popular to pre-adolescent kids
about 5-10 years ago (you know The Masters of the Universe).

My only question is, how can someone that actually believes this garbage
function in American society?

My only concern is, what if some of what he is saying is actually true?
I only hope that The Supreme Being (tm), if there is one, doesn't have that
sick of a mind.

I think it was Einstein that said that God must have a sense of humor.

I hope so,

-- 

   Jim Batka  | Always remember ...                        | Buckaroo
   Modemman   |    No matter where you go, there you are!  |   Banzai
--------------+--------------------------------------------+--------------
It is very    | Work Email:  BATKAJ@CCMAIL.DAYTON.SAIC.COM | Elvis is
often easier  | Home Email:  JBATKA@DESIRE.WRIGHT.EDU      |   DEAD!
to get for-   +--------------------------------------------+--------------
giveness then | 64 years is 33,661,440 minutes ...         | Beatles:
permission!   |    and a minute is a LONG time!            |   Yellow Submarine
Newsgroups: sci.astro
From: dbriggs@rp.CSIRO.AU (Daniel Briggs)
Subject: Re: astronomers vs researchers (was: Re: research vs commercial grade)
Organization: CSIRO Division of Radiophysics/Australia Telescope National Facility
Date: Wed, 27 Jan 1993 06:58:25 GMT

In article <93025.192111LABBEY@GITVM1.BITNET> <LABBEY@GITVM1.BITNET> writes:
>The unfortunate fact is that the word "research" is only used (in astronomy)
>by the purveyors of inexpensive telescopes.

I dunno about you, but I'm doing "research".  So are most of my
colleagues.  The distinction between observation and experiment is
semantically useful, but in practice I've never personally seen a
whole lot of difference.  Unless they are trying to make a fine
distinction, most people use a pretty broad definition of the word
research.

-- 
| Daniel Briggs  (dbriggs@atnf.csiro.au)                 |  USPA B-14993
| Australia Telescope National Facility                  |      DoD #387
Support the League for Programming Freedom   (info from lpf@uunet.uu.net)
From: max@west.darkside.com (Erik Max Francis)
Newsgroups: sci.astro
Subject: Re: Accretion Question
Date: 24 Jan 93 20:15:18 GMT
Organization: The Dark Side of the Moon +1 408 245 SPAM

moroney@world.std.com (Michael Moroney) writes:

> An exception may be our own moon, one theory was a Mars-sized thing hit the
> proto-Earth and blasted a whole bunch of material into Earth orbit, and this
> became the Moon (through a similar process).  This brings up teh question
> why there aren't more large satellites of the inner planets, the only others
> are the two probably captured asteroids around Mars.

I've heard of this proposal.  Computer simulations (several that I hvae 
seen) also seem to back it up, which indicate that it's certainly 
possible, though that may not be the way it happened.

I don't think that there's much of a likelihood that _all_ of the inner 
system planets would have been disrupted in this way.  For one thing, not 
every trajectory between two large bodies will create a captured moon -- 
very few, in fact.

Second, I wouldn't think that such an event was terribly likely -- that 
is, a _big_ object falling into the inner solar system.  (I think there 
was a proposal a while ago that Venus came from outsystem, disrupted 
planets, changed axial tilts, etc., and settled into orbit, which would 
explain its strange rotational period.  I don't know how much credit this 
idea was given, though.)


Erik Max Francis  -)(-  ..!apple!uuwest!max  -)(-  max@west.darkside.com   __
USMail: 1070 Oakmont Dr. #1; San Jose, CA  95117  ICBM: 37 20 N 121 53 W  /  \
Like strategic games of interstellar conquest? . . . Ask about UNIVERSE!  \__/
-)(- Omnia quia sunt, lumina sunt; all things that are, are lights. -)(-
Newsgroups: sci.astro
From: gak@wrs.com (Richard Stueven)
Subject: Re: New planet
Reply-To: gak@wrs.com
Organization: Wind River Systems, Inc.
Date: Tue, 26 Jan 1993 21:08:55 GMT

In article 24349@organpipe.uug.arizona.edu, jscotti@lpl.arizona.edu (Jim Scotti x2717) writes:
>
>  This has been covered before in this newsgroup.  This object is
>definitely NOT a _planet_, but rather a minor planet or possibly even
>a comet. 

Months and months ago, there was quite a debate here over what exactly
qualifies a celestial body to be called a "planet" as opposed to an
"asteroid" or a "failed star" or a number of other names.  I really
don't want to open that can of worms again, but did we ever decide?
(After all, what Usenet says goes, right?  :-)

thx
gak
107/H/3&4

---
Richard Stueven        gak@wrs.com         attmail!gakhaus!gak        107/H/3&4

	That whenever any form of government becomes destructive to these ends,
	it is the right of the people to alter or to abolish it, and to
	institute new government, laying its foundation on such principles and
	organizing its powers in such form, as to them shall seem most likely
	to effect their safety and happiness.

Newsgroups: sci.astro
From: jeffp@netcom.com (Jeff)
Subject: Edmund AstroScan FOR SALE
Organization: BeHereNow
Distribution: usa
Date: Sat, 23 Jan 1993 03:08:45 GMT


Edmund Astroscan 4" Reflecting Rich-Field Telescope.
Includes Base, Tripod Mount, 28mm RKE, Lens Cap, 2.5x
barlow, sighter, eyecup, strap, original packing styro.

$275 includes shipping.

Jeff-
408 946-6743
.
From: jrbd@craycos.com (James Davies)
Newsgroups: sci.astro
Subject: Re: Frosty the telescope
Date: 22 Jan 93 21:15:57 GMT
Organization: Cray Computer Corporation

In article <1993Jan19.174752.2575@nsisrv.gsfc.nasa.gov> dsc@gemini.gsfc.nasa.gov (Doug S. Caprette Bldg. 28 W191 x3892) writes:
>
>In article <1jgr7eINN11f@usenet.INS.CWRU.Edu>, clv2@po.CWRU.Edu (Clayton L. Van Doren) writes:
>
>>Also, how does one keep the scope from frosting over on the
>>first place?
>>
>
>2. Build yourself a heated dewcap ( takes only a few hours )
>
>A heated dewcap, however, seriously degrades the seeing right in front of
>the objcetive, where it does the most harm.  A non heated dewcap, at least 
>as long as the objective diameter, should help quite a bit.  Also, don't leave
>the scope pointed up toward the sky for long periods of time when it is not
>being used, and be sure to cover the objective if you go inside to warm up.
>
>Condensation is a rather complicated phenomenom involving phase change and
>radiative heat transfer.  The dewcap restricts radiation from moisture near
>the objective, or the corrector for a SCT to the sky which has a very low
>brightness temperature.

I've found frosting of eyepieces to be a problem on cold nights also.
I've found that keeping my equipment in the back of my station wagon
(so that it has the hatch over it) helps keep it less frosty, and
also helps keep dew off of the charts and such during warmer weather.
You can un-fog an eyepiece by wrapping your hand around the barrel for
a few minutes, although you have to take off your glove for this and
will wind up with a cold hand instead :-).  Also, breathing on a cold
eyepiece is a real bad idea -- breath condenses really well on the
lens surface, and takes forever to clear up.

My main optics don't frost up, however, since I use a Newtonian --
there's nothing like a five-foot dewcap to keep the mirror clear :-).
From: asnd@reg.triumf.ca (Donald Arseneau)
Newsgroups: sci.astro
Subject: Re: Frosty the telescope
Date: 24 Jan 1993 01:45 PST
Organization: TRIUMF: Tri-University Meson Facility
Distribution: world
NNTP-Posting-Host: reg.triumf.ca
News-Software: VAX/VMS VNEWS 1.41    

In article <1993Jan22.211557.11926@craycos.com>, jrbd@craycos.com (James Davies) writes...
>I've found frosting of eyepieces to be a problem on cold nights also.
>You can un-fog an eyepiece by wrapping your hand around the barrel for
>a few minutes, although you have to take off your glove for this and
>will wind up with a cold hand instead :-).  Also, breathing on a cold
>eyepiece is a real bad idea -- breath condenses really well on the
>lens surface, and takes forever to clear up.

I find that eyepiexes fog up by looking through them!  I think it is the 
moisture coming from my eye.  Often standing up straight for half a minute
lets it clear up; sometimes I lift out the eyepiece, hold the barrel in my 
fist, and wave it around.
Newsgroups: sci.astro
From: randolph@est.enet.dec.com (Tom Randolph)
Subject: Re: Refurbishing Observatory...SURPRISE !!
Organization: Digital Equipment Corporation
Date: 21 JAN 93 13:45:54    


In article <1993Jan20.020718.14371@adx.adelphi.edu>, jf4527@adx.adelphi.edu (Jamie Fitzpatrick) writes...
>it was something special. It had all brass fittings. On the front
>was inscribed..." Alvin Clark & Sons    1877     Cambridgeport Mass."

WOW.

Ever hear of the Yerkes 40" refractor? Largest refracting telescope in the
world... and another Alvan Clarke & Sons instrument. Nice find! Clarke also
made the telescope (18" refractor, if I recall correctly) that discovered the
companion of Sirius.

Your Criterion is equivalent to the late Baush & Lomb Schimdt-Cassegrains. B&L
bought them out a few years back, and has since discontinued the line. If you
ask around at some of the big astro dealers, you can proabably still get
accessories for it.

-Tom R.   randolph@est.enet.dec.com
Xref: sparky sci.astro:14322 sci.physics:23314
From: mcirvin@husc8.harvard.edu (Matt McIrvin)
Newsgroups: sci.astro,sci.physics
Subject: Re: Modelling the expanding universe
Date: 22 Jan 93 22:35:44 GMT
Article-I.D.: husc.mcirvin.727742144
Distribution: na

mcirvin@husc8.harvard.edu (Matt McIrvin) writes:

>Milne's cosmology obeyed a kind of cosmological principle without
>incorporating general relativity (at least not obviously).  The galaxies
>were supposed to be literally flying out through Minkowski space from a
>Big Bang that happened at one point.  They therefore formed an
>expanding sphere which, seen from outside, appeared to have a center
                         ^^^^^^^^^^^^^^^^^

Oops.  Don't take that too literally-- since the edge moved at the
speed of light, you of course couldn't see the thing from outside;
it'd be on top of you by the time you did.
-- 
Matt McIrvin
Organization: Stanford Linear Accelerator Center
Date: Thursday, 21 Jan 1993 11:32:21 PST
From: Jon J Thaler <DOCTORJ@SLACVM.SLAC.STANFORD.EDU>
Newsgroups: sci.astro
Subject: Re: "Modeling" the Expanding Universe?

metares@well.sf.ca.us (Tom Van Flandern) says:

> DOCTORJ@SLACVM.SLAC.STANFORD.EDU (Jon J Thaler) writes:

>> If two test particles are placed at rest wrt each other, the Hubble
>> expansion will not cause them to begin to move apart.  That is, the
>> expansion of the universe does not induce any effects that would be
>> interpreted as forces.  Thus, there is no observable effect on bound
>> systems such as the solar system, hydrogen atoms, galaxies, etc.

> Are you saying that galaxies are not really moving apart?  That a tape
> measure connecting galaxies would not continually play out?

No, I'm not saying that.  I am saying that the Hubble recession is a
result of initial conditions, not of repulsive interactions between
the objects or of "dragging" by expanding space.

Consequently, (as I said above) if the initial conditions are zero relative
motion, the Hubble expansion will not create any.  The subsequent motion
of the particles is described solely by their conventional interactions
(electrical, gravitational, etc).

> If so, I think
> your view is in conflict with the big bang theory.  If not, then my
> question stands: why does the space between galaxies expand at the Hubble
> rate, but space in the solar system does not?  -|Tom|-

My view is in agreement with the BB, and your question has been answered.
Space doesn't "expand" the way you suggest.
From: kristin@head-cfa.harvard.edu (Kristin Kearns)
Newsgroups: sci.astro
Subject: Re: Cosmology/Galaxy textbook ?
Date: 26 Jan 93 16:39:35 GMT
Organization: totally lacking.


I took a class last semester that used the text "Cosmology: the Science of the
Universe" (how original!) by Edward R. Harrison.  It is a readable text, with 
even a glimmer of humor now and then, but it doesnt skimp on the math when 
necessary, and gets deeper into the fundamentals of cosmological theory,
particularly various models of the universe, than most introductory texts.  
Definately not a "gee-whiz-for-non-science-types" book.  The major drawback is 
that it was published in 1981 (Cambridge University Press), and is thus a little 
out of date in some areas.  Also, this may make it hard to find.  (If it helps
to define the level, the class was an independent study in my last year undergrad
in astro.)

-kristin
From: calloway@hplvec.LVLD.HP.COM (Frank Calloway)
Date: Tue, 19 Jan 1993 14:48:44 GMT
Subject: Re: Super Polaris vs. Classic C8?
Organization: Hewlett-Packard Co., Loveland, CO
Newsgroups: sci.astro

>  The Super Polaris is a good mount. I am not very impressed with Celestron
>  fork mounts, after experiancing a C-8, C-11 & C-14 that are fork mounted.
>  I find the german equatorial mounts that Celestron are now producing a lot
>  more stable.

>  One C-8 was so bad (and it was BRAND NEW) that it was unusable (visually)
>  over 200X magnification, and since I am mostly interested in
>  AstroPhotography, this certainly couldn't work - I got rid of it.

>  So, German Equatorials are the way to go.

>  Steven Williams - Astronomer.

I think Steven's comments are an oversimplification.  The Ultima 8 from
Celestron is very stable; none of the gross wandering at 200X that Steven
has seen in other models.  Its fork arms and tripod are massive in
comparison to the other C8s.  Thus, it depends on which C8 you use.

As a counterpoint, I've used the Super Polaris mount on a couple of
scopes and thought it was a bit crude compared to the fork mounts.  For
me, the setting circles were marginally useful and the slow motion 
controls and clutches felt coarse and cheap.  On the other hand, I'd 
expect the new Celestron German equatorial mounts made by Losmandy to 
be quite good.

Frank Calloway 
Newsgroups: sci.astro,rec.radio.shortwave
From: oler@rho.uleth.ca (Cary Oler)
Subject: Daily Solar Geophysical Data Broadcast for 23 January
Organization: University of Lethbridge
Date: 24 Jan 93 19:14:45 GMT

!!BEGIN!! (1.0) S.T.D. Solar Geophysical Data Broadcast for DAY 023, 01/23/93
10.7 FLUX=106    90-AVG=140        SSN=047      BKI=2100 0012  BAI=002
BGND-XRAY=B1.1     FLU1=1.3E+05  FLU10=9.4E+03  PKI=2000 0011  PAI=003
  BOU-DEV=015,006,004,003,004,004,006,015   DEV-AVG=007 NT     SWF=00:000
 XRAY-MAX= B2.3   @ 1236UT    XRAY-MIN= B1.0   @ 1907UT   XRAY-AVG= B1.1
NEUTN-MAX= +003%  @ 2040UT   NEUTN-MIN= -002%  @ 0840UT  NEUTN-AVG= +0.4%
  PCA-MAX= +0.1DB @ 2230UT     PCA-MIN= -0.3DB @ 0910UT    PCA-AVG= -0.0DB
BOUTF-MAX=55415NT @ 0011UT   BOUTF-MIN=55390NT @ 1945UT  BOUTF-AVG=55408NT
GOES7-MAX=P:+118NT@ 2111UT   GOES7-MIN=N:+005NT@ 1005UT  G7-AVG=+083,+025,+010
GOES6-MAX=P:+134NT@ 2110UT   GOES6-MIN=E:-011NT@ 2152UT  G6-AVG=+099,-000,+034
 FLUXFCST=STD:105,105,105;SESC:105,105,105 BAI/PAI-FCST=005,010,015/005,013,020
    KFCST=1111 1113 3311 1111  27DAY-AP=003,005   27DAY-KP=0012 1210 0011 0123
 WARNINGS=
   ALERTS=
!!END-DATA!!
Newsgroups: sci.astro
From: reinhard@stsci.edu
Subject: Wanted: Focus Screen for Olympus 0M-1
Organization: Space Telescope Science Institute
Distribution: na
Date: Fri, 22 Jan 1993 15:41:32 GMT


I am looking for focusing screens for an Olympus 0M-1 camera.

The type needed is for astrophotography.  I think the type
is numbered "1-8".

Thanks.

Kent Reinhard
Space Telescope Science Institute
Baltimore,  Md.
From: max@west.darkside.com (Erik Max Francis)
Newsgroups: sci.astro
Subject: Re: The Moon's Orbit (Re: Solar Eclipse Question)
Date: 28 Jan 93 03:47:33 GMT
Organization: The Dark Side of the Moon +1 408 245 SPAM

tjt@Jpl.Nasa.Gov (Tim Thompson) writes:

> nailed to Jupiter's equatorial plane (likewise Saturn, etc.). Remember that t
> Moon's mass, expressed as a fraction of the parent planet's mass, is by far t
> largest in the solar system, which makes the Earth-Moon pair unique. The Moon
> simply too massive to have been forced into the plane of the Earth's equator 

Eh?  The Pluto-Charon ratio is bigger, ain't it -- and by quite a bit?


Erik Max Francis  -)(-  ..!apple!uuwest!max  -)(-  max@west.darkside.com   __
USMail: 1070 Oakmont Dr. #1; San Jose, CA  95117  ICBM: 37 20 N 121 53 W  /  \
Like strategic games of interstellar conquest? . . . Ask about UNIVERSE!  \__/
-)(- Omnia quia sunt, lumina sunt; all things that are, are lights. -)(-
Newsgroups: sci.astro
From: maytag@rintintin.Colorado.EDU (MAYTAG CHRISTOPHER P)
Subject: Unguided astrophotography - FAQ? 
Organization: University of Colorado, Boulder
Date: Wed, 27 Jan 1993 06:39:27 GMT


I'm looking for a FAQ regarding unguided, tripod-mounted astrophotography. I've tried a few rolls, and have had acceptable (but very improvable) results. I'm particularly interested in any info on films (I've tried Kodak gold plus 400, 1600), exposure times (this was my biggest problem short of grainyness in the 1600 prints), and the 'fogging' limit in 'near-city' light conditions. What kind of light will fog film fastest? Can someone send/post an exposure guide for common film speeds?

I'd appreciate any help!

-Chris

Newsgroups: sci.astro,sci.skeptic