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  *thE_bUG* writes:
> I just got to read about some obscure African tribe called the Dogon who
> startled the scientific world in the 1940-50s when they shared their
> knowledge of Sirius A and B with some European anthropologists
  Read Carl Sagan's account of this "startling knowledge"; it appears in
either "The Dragons of Eden" or "Broca's Brain."  He chalks it up
to talkative missionaries.
-- 
-----                                      
Michael Richmond                   "This is the heart that broke my finger."
richmond@astro.princeton.edu       http://astro.princeton.edu/~richmond/

Hi all,
Sorry if this is a really lame question, but is there a web page or ftp site 
where I could find astronomical data, to be more specific: the position of 
stars with respect to the earth? Is there much available data of the 
angles/distances of many of the stars in this galaxy? A rather vague question 
I know, but I haven't been able to find anything on the web so far. I would 
appreciate any replies by email, thank you for your time.
Michael

"InLink Support" (markew@usa.net) writes:
> I would think that images of the Cydonia Mensae would be taken, but not
> because of Face Mesa, but because it is an interesting portion of the
> global escarpment, which may have at one time been a sea shore, and hence
> could tell us a lot about the history of the Martian hydrosphere.
>  
    No. Malin is the principal investigator (as he says in his Web-page)
and, despite his nasty desdain towards our claims in Cydonia (he does not
have a clue about those silly remarks as "the wisdom is that all this is
nonsense")... despite alll this he recognizes that the 'popular demand'
of 'good imaging, if possible, of Cydonia' is a MUST from public relations
point of view. So he sets squares around 'Face' and 'City Square' and
"D&M;" and says that these specific targets ARE in the planned project...
he does not give any 'special priority' to these Cydonia targets and
even in his desdain contends that the main reason of such images is
for something as you have above pointed out... the deep reason for
'no priority' is because he and NASA's team of drivers are powerless
to control the details of the orbit for ANY specific region: this is
obvious consequence of what I have clearly posted in this thread: the
spacecraft will scan orderly all martian surface in shifted 12 sectors
and that is ALL that MGS can possibly do. Actually the rusian-german
project will do similar scanning and as V. Moroz e-mailed to us
"Cydonia MUST be covered, but without special priority".... again because
such priorities cannot be realistically programmed for ANY particular
region.
--
Angel, secretary (male) of Universitas Americae (UNIAM).
     http://www.ncf.carleton.ca/~bp887

>   wa2ise@netcom.com (Robert Casey) writes:
>  In the northern hemisphere, the Sun and Moon are seen traveling
>  across from east to west, and passing closer to the south point of
>  the horizon than the northern point on the horizon (in the temperate
>  zones, not artic circle area).  So, the first quarter moon in evening
>  is seen facing to the right and slightly down an hour or 2 after
>  sunset.  Now, in South america people there see the very same 1st
>  quarter moon facing to the lower left.  There the Sun and Moon 
>  travel from east to west, but passing closer to the north than south
>  points on the horizon.  
>  
>  So, yes, the phases of the moon would look inverted there.  
>  
>>>>
Thanks! I've known astronomy for years, but this never occured to me (til an Australian writer brought it up )...
Ralph
www.clysmic.com/home

I am just curious if anyone has found any recent
pics of HB posted on the web.  The latest I've seen was
at NASA's page 1 pic taken in May '96.  I'm curious as to 
why NASA hasn't posted any more since then taken via the HST.
I was under the impression that NASA reserved time on the HST
during July, August, September, and October '96 to view Hale
Bopp.  
Mark

Brian Zeiler (bdzeiler@primenet.com) pontificated:
> On 9 Nov 1996 19:12:50 GMT, js@aq.org (Jay Sekora) wrote:
> 
> With a government like the Soviets' at the time, the main motivator
> was furious competition with the US as well as ferocious nationalism.
> Most countries seem to lack that sense of fierce pride these days, and
> the culture of liberalism places a higher priority on cute social
> programs than on long-term goals.  So, not only do I not see a
> motivation for US leadership in space exploration, but I see a lack of
> interest from the entire population.
> 
> In that sense, government is largely out of the picture.  Private
> funding is needed, or perhaps a philanthropic effort (like if Bill
> Gates donated $1 billion for a Mars probe or something), or a
> combination of both.  The private support of SETI with Project Phoenix
> is a good example of private wealth saving a project with eroding
> government support and nonexistent public interest.
You are dreaming on such a high order.  I cannot conceive of Bill
Gates dropping $1 billion on a Mars probe or something for no return
on investment.  He would probably prefer the slower (and more
profitable approach) of paying for schools, universities and
scholarships to train the next generations of engineers and
scientists.
Below, I will outline my Modest Proposal for jump-starting the private
sector space industries.
> >And the sort
> >of very large, long term investment that I think is necessary to see a
> >return on investment in space is something that US companies anyway tend
> >not to be all that good at.  (To be fair, governments seem to have
> >trouble with it too.)
> 
> Well, I wouldn't be too sure.  Look at the commitment to such projects
> like Iridium, which has been going for years now with billions
> invested.  Or look at the massive capital expenditures by the telcos
> for the Internet infrastructure.  I just think we need to find a way
> to make space profitable, and the development will take on a life of
> its own.
Oh, brother.  Come here, Unca wanna talk with you...
Iridium has not had real billions invested as of yet (or at least I
haven't heard of a massive cash infusion yet).  They have the
financing set-up, but it relies on a heavy cash flow coming from the
ultimate Screw-The-Telcos scheme that Iridium promises to be.  My
problem with Iridium is that I think it is really a massive waste of
money to further clutter near-Earth space for out-of-date technology.
As for the Internet infrastructure.  You are an idiot, aren't you?  I
want to point one thing out to you right here, right now:  The
National Science Foundation and the DOD's ARPA paid for the Internet
infrastructure.  The U.S. FEDERAL GOVERNMENT paid a lot of money to
AT&T; and other companies to develop the Internet technologies.  It
wasn't until Al Gore spilled the beans about the private club called
the Internet that the Telcos and Long-Distance Telecom companies that
they all suddenly developed the Internet religion.
As well -- there was a market already *there*.
Space does not have a lot of readily commercial activities right now.
Space mining?  Do you really want the enviromentalists screaming at
you for bringing even more metal to clog our landfills?  As well as
the energies involved in getting to the minerals, refining in orbit or
carrying the asteroid to Earth...  It's just astronomical.
Micrograv manufacturing?  The basic research on just what can actually
be *done* in Micrograv is just beginning!
Super-pure vacuum fabrication?  See above.
So, you say, what is the solution?  It has several fairly easy to
remember steps (although the steps are very hard -- a good sign in my
books :-) ):
1. Either cancel outright further research on Ballistic Missile
Defence to defend America from an aging and corroding Soviet missile
fleet, or spend a lot of money on it but earmark money for:
	The Delta Clipper.
	I have no problem with McDonald-Douglas winning the contract, but
	make sure they have competition.  Let them both build their ships
	and tell them the first one to get their thing working on a
	regular basis and economically enough for the public space program
	gets the contract.
	Clean-up the laws so that way the legal responsibilities and
	rights of private launch firms are figured out up front.  Get rid
	of that unknown, because we are going into an even bigger unknown.
2. Build the space station, but make sure everyone realises it is a
research and test-bed.  The *next* station will be bigger and a
public-private co-venture.  After Space Station Alpha finds out what
can be done in micrograv and letting the private sector find out first
hand what they can do, lining up private financing should be a lot
easier than lining it up without a working prototype.
3. The *next* space station will be a big private-public co-venture
where public space research shares space (and maybe results?) with the
private space research initiatives.  The big thing is the *next* space
station will have a space-dock for building Step 5.
4. Using Mir and the new space station, private and public researchers
work on creating self-sustaining ecosystems that can survive the
rigours of space and is very robust.  This will form the heart of step
5.
5. Build, in orbit, a space ship that can be used to travel anywhere
in our solar system (or even just the inner solar system).  It will
have several modules: C&C;, Engineering-Propulsion-Power, Sciences, and
the Eco-Habitat which will support the human explorers.  Each section
will be fairly redundant so that the ship could continue to operate
even if two of its sections are lost en route and an emergency return
home is needed.  The private sector can be involved if they want: They
can learn the do's and don'ts of space ship construction and maybe
finance their own space ships based on the inital risky prototype.
6. Explore our inner solar system and figure out basic science issues
and research & develop interplanetary travel systems.
7. Allow private people, companies, etc. to colonize the Moon, Mars,
etc.  The colonies must be private, but they can ask to be part of
nation states.  No colony can actually belong to nation states, but
affiliation is allowed.
The rest is the future...

   : No, it's done with reaction wheels - popularly known as "gyros".
In article <55taga$ip3@pith.uoregon.edu> cjones@gladstone.uoregon.edu
(Christopher Michael Jones) writes: 
> Reaction wheels are not really gyros.
Yes.  The original poster did say "popularly known," which is also
probably correct.
> Actually, I believe the primary method for changing the attitude of
> Hubble is through magnetic torquing.  There are devices on Hubble
> that use the magnetic field of Earth to put torque on the
> spacecraft and change its attitude.
Not exactly.  Reaction wheels are the primary control mechanism, but
if nothing else were done, the wheels would reach arbitrarily high
speeds as they compensate for unbalanced torques.  (Unwanted torques
come from air drag, gravity gradient, and light pressure--anything
else?)  Magnetic torquers are used to "unload" the reaction wheels.
--
Steve Willner            Phone 617-495-7123     swillner@cfa.harvard.edu
Cambridge, MA 02138 USA                 
(Bad news service; please email your reply if you want to be sure I see it)

In article <55s42i$nku@news.be.innet.net> year1440@club.innet.be (Jo
Helsen) writes:
> I always wondered whether it makes sense to claim that "we see the
> star as it was 100 years ago". Such a claim only makes sense when
> you start from one absolute timeframe that applies everywhere in
> the universe. But thanks to Einstein we know that there is no such
> thing.
On the contrary, there is no difficulty (in principle, at least) in
synchronizing the clocks of distant observers _as long as they are
not moving with respect to each other_.  Clocks on Earth, for
example, can be synchronized to the microsecond level (if not
better), even though it may take tens of milliseconds for radio waves
to travel from one clock to another.
Even though the stars move with respect to each other, the speeds are
much smaller than the speed of light.  An observer located near a
star 100 light-years away could (again in principle) synchronize his
clocks with ours to pretty good accuracy and report what the star was
doing at a specified time.  Of course it would take at least 100
years for the report to reach us.
--
Steve Willner            Phone 617-495-7123     swillner@cfa.harvard.edu
Cambridge, MA 02138 USA                 
(Bad news service; please email your reply if you want to be sure I see it)

In article <11-07-1996.1174@worldchat.com> jcarroll@worldchat.com
(Jim Carroll) writes: 
> A fellow teacher of mine was reading a geography book in which it
> said that the atmosphere is thicker at the poles.
You might check exactly what "thicker" is supposed to mean.  The
atmosphere is _denser_ near the poles (at a given "height above sea
level") because the temperature is lower and because the acceleration
of gravity is a little higher.  (The poles, or at least the notional
sea level, are closer to the center of the Earth, and there is no
centrifugal force.)  On the other hand, the _scale height_ is smaller
near the poles, at least into the stratosphere, for the same reasons.
At the South Pole, the surface of the Earth is actually a couple of
kilometers above sea level, so one has to be a bit careful about
exactly what one is saying.  Also, I'm not sure whether there might
not be some effect that changes the scale height of the upper
atmosphere.
--
Steve Willner            Phone 617-495-7123     swillner@cfa.harvard.edu
Cambridge, MA 02138 USA                 
(Bad news service; please email your reply if you want to be sure I see it)

stooke@sscl.uwo.ca wrote:
> Venus         online   http://cdwings.jpl.nasa.gov/pds/public/magellan/
>                                                          midrcd_query3.html
URL has Moved - now at:
http://www-pdsimage.jpl.nasa.gov/PDS/public/magellan/midrcd_query.html
>  Europa       online   http://flgsvr.wr.usgs.gov/europa/europa.html
Also moved, now at:
http://wwwflag.wr.usgs.gov/USGSFlag/Space/europa/europa.html
Keith Edkins
Cambridge, England

I have a question if someone could help, not quite related to what your
talking about.
Is momentum always conserved during interactions (say..fluid flow through a
nozzle)?

Keith Edkins wrote:
> 
> Jim Carroll wrote:
> >
> > Just a follow up to this question.  Another thought is that the earth is
> > slightly flattened out at the poles like an ellipsoid.  The poles are
> > about 20km closer to the equator and therefore the pull of gravity is
> > slightly greater.  If we assumed the atmosphere  to be symmetrical, then
> > it would be 20 km thicker at each pole.   Anyone offer a different
> > explanation?
> >
> 
> I don't think that's it - it sounds far too much of a difference for one
> thing. I reckon pressure would equalise itself on the surface of the
> ellipsoid, rather than over an imaginary sphere touching the equator and
> 20km above the poles. My explanation would be that equatorial air is
> warmer
> and therefore less dense than polar air, so you need a greater depth of
> it to create the same pressure.
> 
> Keith Edkins
> Cambridge, England
I haven't yet noticed any mention of the Earth's rotation.  Because
of the effect of "centrifugal force" the average adult weighs about
1/4 pound less at the equator than at the poles.  The effect must
obviously become more pronounced at greater elevations; and air
pressure is the result of the weight of all the air over a given
point.  So wouldn't that account for the decrease in pressure at
the equator?
-- 
		--Steve McAllister (I'm all for self-expression.
                  'Course, that's just my opinion...)
E-Mail Address: mcallist@es.com

Some clueless questions on gravity and black holes:
It's said that light photons cannot escape the black hole, as
the required escape velocity is higher than the speed of light.
OK, does gravity "particles" travel at the speed of light?
Vaguely remember that a theory of gravity said something
about gravity being "enforced" by "gravity particles). ?
If that is right(?)!?. then how do the gravity
particles escape the black hole, if photons cannot?  Does gravity
grab "gravity particles"?
If gravity particles couldn't escape the black hole, then we would
never know if there was a black hole nearby, then
So I have missed something in the above.
(choppy writing due to typing half blind,
Netcom is dog slow tonight!)

paul.johnson@gecm.com (Paul Johnson) wrote:
>In article <32853A38.38E7@gte.net>, ashes@gte.net says...
>>I read in a science book that there is a greater posibility of a
>>printinng press exploding and forming webster's dictionary completly by
>>accident; as opposed to the world being created from some dead matter.
>Thats not a science book, thats a lying book.
>If you are interested in what biology *really* says about our origins then I
>suggest you have a look through the talk.origins FAQs.  Please don't trust
>the versions you read in creationist literature: they are uniformally
>straw men.
Creationism is not science, Ashes.  Check things out, investigate for
yourself.  
>Paul.
>-- 
>Paul Johnson            | GEC-Marconi Ltd is not responsible for my opinions. |
>+44 1245 242244         +-----------+-----------------------------------------+
>Work:        | You are lost in a twisty maze of little
>Home:     | standards, all different.
Regards,
Stoney

Ari Rothman  wrote:
>I have to draw exception to the current attitude that attributes mass
>extinctions to bolide impacts.  There is too little to no evidence of
>this in most mass extinctions.  The K-T extinction took millions of
>years  and can be tied to the draining of inlands seas, climatic changes
>and the preference for fossil collection in North America and Europe.  I
>am not saying a hit did not occur, only that it was not as fatal as some
>say.  Ask a turtle or lizard or alligator, all cold blooded, all
>survived.  Sorry I got off the subject.
I'm not at all patient with claims like this.  The climatic change,
inland seas, yada yada yada are just so stories. I cast a jaundiced
eye on the claim that the extinction took millions of years.  The
extinction of forams certainly did not take this long.  For larger
creatures, such as dinosaurs, the evidence at Hell Creek
is that they were doing fine to within 0.25 Ma of the boundary
(and perhaps much closer.)  And recall ammonites -- previously
claimed to have died out millions of years before the boundary,
until it was shown otherwise by fossils at another site.
Also, the evidence that an impact *did* occur is very
strong, so saying that something else killed off things only
makes the problem worse: how did the turtles, etc. survive
both that other cause, *and* the impact (an impact that
oh so coincidently occured just near the biggest extinction
in the last 100 Ma.)
     Paul Dietz
     dietz@interaccess.com
     "If you think even briefly about what the Federal
      budget will look like in 20 years, you immediately
      realize that we are drifting inexorably toward a
      crisis"
        -- Paul Krugman, in the NY Times Book Review

From what I found by browsing through the Hubble datasets at
http://marvel.stsci.edu,
it appears that ALL Hubble Space Telescope datasets are subject to a wait
period of
1 year. So exactly 1 year from the time the data was collected, NASA will
release the
data to the public, not necessarily including the finished photograph. 
Mark  wrote in article <3287FF04.34BF@whidbey.net>...
> I am just curious if anyone has found any recent
> pics of HB posted on the web.  The latest I've seen was
> at NASA's page 1 pic taken in May '96.  I'm curious as to 
> why NASA hasn't posted any more since then taken via the HST.
> I was under the impression that NASA reserved time on the HST
> during July, August, September, and October '96 to view Hale
> Bopp.  
> 
> Mark
> 

>You are spamming braindead newbie twits.  The Net does not censor, but it 
>does compartmentalize.  Remove your rancid heap of parrot droppings from 
>sci.chems because if you don't...
>
>Netizens have ways of protecting themselves.  40 million unhappy folks 
>sums to a lot of displeasure.  Suppose each one drops a brief note into 
>your e-mail box? 
>
>I have contacted postmaster@alognet.se  and request that you either learn 
>netiquette or have your plug pulled.
>
>-- 
>Alan "Uncle Al" Schwartz
Oh, get over yourself.  How much actual time did you waste on this?  I'm 
sick to death of flamers, spammers, and me-tooers in the net, but I 
didn't mind reading those few frivolous sentences, and I must say I was 
rather repulsed by this flammable response of yours. 
Grow up, you.
--me

In article <32873F4C.7AA0@courier6.aero.org>, "Walter E. Shepherd"
 wrote:
[deleted]
> deal... nothing magical... but we are impressive... we are the
> cumulative experience of natures experiment... we stand on the shoulders
> of all species which have struggled to survive on this planet.
You lost me right there.  There's been too much evolution going on in
parallel for this to be true.  (i.e. not all other species are our
precursors.)  
--PKS
-- 
There's neither heaven nor hell
  Save that we grant ourselves.
There's neither fairness nor justice
  Save what we grant each other.
Peter Kwangjun Suk 
Musician, Computer Science Graduate Student
[finger suk@pobox.com for PGP public key]

In article <567lo2$84j@ccshst05.cs.uoguelph.ca>, devens@uoguelph.ca (David
L Evens) wrote:
> Peter Kwangjun Suk (suk@pobox.com) wrote:
> : In article <565qni$7og@ccshst05.cs.uoguelph.ca>, devens@uoguelph.ca (David
> : L Evens) wrote:
> 
> : > Erik Max Francis (max@alcyone.com) wrote:
> : > : Well, that's basically what it is right now.  Look at viruses, for
instance.
> : > : Half the scientists think they're alive, half think they're not. 
The most
> : > : common argument you'll hear against is that, "But they're nothing but
> : > : chemicals that perform interesting reactions!"  Well, no kidding, that's
> : > : what all life is.
> : > 
> : > Actually, the most common argument I've seen against considering viri to 
> : > be alive is that they MUST have living hosts to reproduce.  There exist 
> : > no possible set of natural environmental conditions that would allow 
> : > isolated viri to reproduce.
> 
> : Aren't cells the "natural environment" of virii?  If you "isolated" humans
> : in any number of ways, they'd also fail to reproduce.  (In a desert, for
> : example.)  
> 
> Isolated viri don't carry out any life processes, however.  They just sit 
> there, close to chemically inert.
Are dehydrated brine shrimp alive?  Do creatures that enter into severe
forms of suspended animation cease to be living creatures?  Not just
hibernation like arctic squirels, but becoming seriously rock-like. 
Apparently some bacteria can do this.  (This reminds me of a part of
Searle's chinese room:  What if the guy manipulating the chinese symbols
took a sabbatical?  During that time, the simulated intelligence would
cease to function.  What would happen to its consciousness?)
Somehow, temporary inertness doesn't strike me as a disqualification.  One
could imagine a species of self-reproducing machine that was capable of
having a "metabolism" comparable to life as we know it on Earth and of
being stone-cold inert.  
--PKS
-- 
There's neither heaven nor hell
  Save that we grant ourselves.
There's neither fairness nor justice
  Save what we grant each other.
Peter Kwangjun Suk 
Musician, Computer Science Graduate Student
[finger suk@pobox.com for PGP public key]

In article <3286B720.58CFCABE@alcyone.com>, Erik Max Francis
 wrote:
> Peter Kwangjun Suk wrote:
> 
> > In article <565qni$7og@ccshst05.cs.uoguelph.ca>, devens@uoguelph.ca (David
> > L Evens) wrote:
> >
> > > Actually, the most common argument I've seen against considering viri to
> > > be alive is that they MUST have living hosts to reproduce.  There exist
> > > no possible set of natural environmental conditions that would allow
> > > isolated viri to reproduce.
> > 
> > Aren't cells the "natural environment" of virii?  If you "isolated" humans
> > in any number of ways, they'd also fail to reproduce.  (In a desert, for
> > example.)
> 
> Yes.  If one's definition of life procludes reproducing in hosts, that's
> fine.  Parasites require host organisms to live, for instance.  I'd hardly
> say that doesn't make them alive.  I'd say living is a stronger indication
> of life than reproducing -- although both are required for fully-developed,
> evolving life -- but it seems strange to broadly say that viruses are not
> alive because of this.
A combination of the thermodynamic definition with a requirement for
reproduction and a capacity to "evolve" comes very close to a universal
definition of life.  So how about it?  I posit this as "THE definition". 
This would include viruses, but preclude candle flames and formaldehyde
blobs.  
Aside: I've heard of one researcher who challenged an older definition of
life by using chemical blobs.  (This definition had movement, excretion,
growth, and reproduction as four of the requirements.)  Apparently, these
blobs were not soluble in water and would move in room temperature water
in a way that seemed alive.  To top it off, the researcher prepared some
capsules that each contained a droplet of of the same substance stoppered
by a small pebble which in turn was held in place by a waxy seal.  When
the capsules were dropped into the water, some of them would come in
contact with the blob, which would dissolve the seal.  The stoppers would
pop off and sink while the capsules would fill up with water and also
sink.  The contents of the capsule would become part of the blob,
however.  When the blob got large enough this way, it would become
unstable and split into two blobs.  
Anyone see any holes in "THE definition" or in the story above?  (The
provenance of the story is my father, who is a very sharp pathologist.)
> The plural of _virus_ is _viruses_, by the way.
A pity.  I really like those 'ii' plurals.  I much prefer Elvii to
Elvises, for example.  
--PKS
-- 
There's neither heaven nor hell
  Save that we grant ourselves.
There's neither fairness nor justice
  Save what we grant each other.
Peter Kwangjun Suk 
Musician, Computer Science Graduate Student
[finger suk@pobox.com for PGP public key]

In article <3286B720.58CFCABE@alcyone.com>, Erik Max Francis
 wrote:
> Yes.  If one's definition of life procludes reproducing in hosts, that's
> fine.  Parasites require host organisms to live, for instance.  I'd hardly
> say that doesn't make them alive.  I'd say living is a stronger indication
> of life than reproducing -- although both are required for fully-developed,
> evolving life -- but it seems strange to broadly say that viruses are not
> alive because of this.
> 
> The plural of _virus_ is _viruses_, by the way.
(P.S.  It's "precludes", not "procludes"  ;-)
--PKS
-- 
There's neither heaven nor hell
  Save that we grant ourselves.
There's neither fairness nor justice
  Save what we grant each other.
Peter Kwangjun Suk 
Musician, Computer Science Graduate Student
[finger suk@pobox.com for PGP public key]

David L Evens wrote:
> 
> 
> Actually, warmer air needs a lesser depth to create the same pressure,
> since the contribution from each individual molecule is greater with
> higher temperature.
> 
Actually I think my post was rubbish. Surely gasses equalise pressure
sideways, so the atmosphere of a spherical planet would be spherical
regardless of temperature effects.
The snag here is that 'sideways' means something like 'along a
gravtitational equipotential' or 'along a surface normal to the
direction plumblines point' and around the earth these are not spheres.
Perhaps the poles lie deeper in the earth's gravitational field.
That's my today's explanation anyway.
Keith Edkins

> 
> mjwall@con2.com (Michael Wallach) wrote:
> 
> >I am researching Babylonian and Sumerian astronomy.  Can anyone suggest
> >a WWW  or other net resources that would be helpful? I have used various
> >search engines, but have not found anything useful.
The Astronomical Journal volume 72, #8 Oct. 1967 contains "An account of the methods
used in ancient Babylonia for predicting the positions of the planets."  by O.
Neugebauer.  
-- 
James McCann
jmccann@nwlink.com
jmccann@scn.org

spooner wrote:
> 
> rsmith@clysmic.com wrote:
> >
> > This has been diving me crazy! I need astronomical advise ...
> >
> > My question: are moon phases really "inverted" in the southern hemisphere?
> > In other words, at the First Quarter moon, which side is lit, the right or
> > left?? In the northern hemisphere, it's the right side. Is it really the
> > left in Australia and points south? Do the local almanacs/calendars all reflect this, or use a
> > "standard" moon picture (i.e. always the right side)?
> >
> > Thanks...Any help appreciated!
> >
> > Ralph Smith
> > Albany, NY, USA, Northern Hemisphere where it's getting colder every day...
> 
> And also what happens at the equator? ;-)
> mike
I can vouch that at the 1st quarter I see the moon's left side lit when
I am standing up in Melbourne (but if I go silly and lay myself down on
the ground, then depending which way my body is pointing, I can make the
lit side be anywhere I want). 
As to the standard moon picture, I can't say that I recall but my guess
is it would be pointing right.
I might add that there is a map of the world which has been published
with the south pole at the top (and Australia just below) just to
confuse the northerners.
-- 
John Jacq

dean@psy.uq.oz.au (Dean Povey) writes:
[Stuff deleted]
>>> From the Web page:
>>> "[Autodynamics] explains the perihelion advance of Mercury, Venus, Earth
>>> and Mars, and all Binary Star precessions for which we have data."
>>Where is your data posted?
>Well, I didn't  come up with this theory so I must confess I don't know.  But
>this is a good point.  I'll email someone in the SAA and see if they can
>put the data up on their web page.
Oops sorry, put this down to a late night and too much reading/coding
:(.  *Smacks self in forehead* The figures are there for all and
sundry, they can be found at: http://www.autodynamics.org/Cosmos/Gravity.html
Here is an extract:
=====>
SR and AD Comparison
The general relativity equation for advance of the Mercury perihelion is: 
                 6 pi GM 
          T  =  ----------           [Pardon my ascii, DGP]
              c^2 r (1 - e^2)
Where e = eccentricity, c = light speed and G, M, and r have the usual
meaning in this paper.
This equation yields, in a century: 
                  42.4" for Mercury
                     8" for Venus
                     4" for Earth
                     1" for Mars
In AD gravitation, the perihelion advance for each planet is
proportional to the square root of the division of the solar mass by
the orbital radius power 3.
             Tp = sqrt(M / r^3)      [ditto: DGP]
If the Mercury value is taken as 43", the values for the other planets are: 
                   Venus = 16.8"
                   Earth = 10.4"
                   Mars  = 5.5"
[These] values are equal to Hall's empirical values and close to the
expected values calculated by Newcomb.
The big difference between SR and AD occurs when the distance to the
Sun is smaller. If the distance is 1/3 of the Mercury radius the values
are:
                     GR = 129"
                     AD = 223"
If the radius is 1/5 of Mercury the values are: 
                     GR = 214"
                     AD = 481"
We see that the proportional difference increases with decreasing
radius. Putting a probe close to the Sun can easily test, in a short
time, if its perihelion advance is a natural phenomenon beyond the
planetary perturbation and if the values are given by GR or AD
gravitational equation.
<==========
The rest is on the web page.  There are also figures for the binary star
DI Herculis. 
Sorry about that. 
Dean.

mbcx6prn@stud.man.ac.uk wrote:
> 
> A photon is used in physics to explain certain properties of light.
> The best explanation of a photon I can give is that it's a travelling
> packet of energy with no mass but can exert a force on the medium it
> interacts with.
> 
> Paul Norman.
And linear momentum, E=h.f is the energy, linear momentum= h.f/c
f=frequency
h= Planck's constant
-- 
John Jacq