What can I image in 5 minutes?

On 6 Dec, 21:49, "Androcles" wrote:
"Mark McIntyre" wrote in message

...: Androcles wrote:

: "Mark McIntyre" wrote in message
: ...
: : Androcles wrote:
: : So the Seven Sisters is an optical septuplet?
: :
: : Yes.
:
: I should have added that this is commonly called an asterism, or, if
: large enough, a constellation.

Ah... astrology spam. Pictures in the fire, pictures in the clouds,
pictures in the stars. I was under the mistaken impression
that these were sci. newsgroups but maybe Kelleher is talking
to the right people after all.


You are an astrological child of these guys.

http://www.belugalakeobservatory.com...py_700x700.jpg

Every one of those stars returns to a location in 23 hours 56 minutes
04 seconds or 3 minutes 56 seconds earlier based on the calendar
system.

Want to see warped space then enjoy that wonderfully 'predictive'
calendrically driven system you inherited from Flamsteed via Newton -

http://www.opencourse.info/astronomy...phere_anim.gif

Astrologers !, you do not know the half of it and the worse part is
that it takes only two sticks and a stopwatch to undo 3 centuries
wortth of empirical junk based on muddleheaded reasoning -

"... our clocks kept so good a correspondence with the Heavens that I
doubt it not but they would prove the revolutions of the Earth to be
isochronical" John Flamsteed












: Then all stars are doubles. No matter which star you look at
: there is another within 30 arc seconds of it.
:
: Indeed. I guess the point is, how many appear single stars visually but
: resolve into a pair at moderate resolution?

Visually meaning less than 6th magnitude?
:
: From the Moon, yes. They must a be double city.
:
: Indeed. From the moon, London, Croydon and Slough would appear one city
: too. Thats kinda the point.

Bad example. Croydon is inside the M25, Slough outside on the M4.
http://apod.nasa.gov/apod/image/0304/london_iss_c1.jpg
Crawley would be seen before Slough and so would Dagenham,
even tiny Sheerness, they emit more light. Can't tell with Dartford,
it is under cloud cover in the image.

:
: Ok, and so is Bumf**k, Alabama.
:
: Childish.

That's the point. Double stars (and lists of) are a childish concept,
nothing more than astrology spam of no import or significance
whatsoever. Meaningless drivel to be given as much weight as
Kelleher's nonsense or any other crackpot's silly ideas.

"Paul Schlyter" wrote in message
...
: In article ,
: Androcles wrote:
:
: "Paul Schlyter" wrote in message
: ...
: : In article ,
: : Androcles wrote:
: :
: : "Paul Schlyter" wrote in message
: : ...
: : : In article ,
: : : Mark McIntyre wrote:
: : :
: : : (/are/ there any binary systems that can be resolved with the
naked
: : eye? )
: : :
: : : *Any* binary system can be resolved by the naked eye if only viewed
: : : from a close enough distance. :-)
: :
: : If it IS a binary, sure.
: :
: ::-) ...can you name even one binary system which isn't binary? g
:
: Oddly and amusingly as it may seem to you, yes.
: A binary system is only a binary if
: a) it has two stars.
: b) the stars are orbiting a common barycentre.
: c) it can be resolved into two stars OR the velocity
: of at least one of the pair can be measured spectroscopically.
: The wild conjecture of an 18-year-old kid isn't sufficient
: evidence for finding a binary system.
: Do you agree?
:
: If the system isn't a binary, then the question whether it's a binary
: or not has already been answered. There are no binary non-binaries,
: don't you agree?

Yes, I agree, but I can name a binary which isn't a binary;
first we have to establish what criteria caused it to be called a
binary in the first place. A tiger is a cat, but a cat isn't a lion.
If you have some other criterion for determining what
a binary is besides what I've given then let's hear it.


:
: : : Of course we also have Epsilon Lyrae, where the wide pair (AB)+(CD)
: : resides
: : : some 3 arc minutes from one another and can be resolved by people
with
: : : keen eyesight.
: : Epsilon Lyrae is often used by skywatchers as a test of
: : : their eyesight. And this is a physical pair, not an optical double.
: :
: : Widely separated and nearby. Period?
: :
: : That period is unknown but must be very long: at least hundreds of
: : thousands of years, probably more. So far, no relative motion has
: : been detected in that wide pair. Even the two narrow pairs of Epsilon
: : Lyrae each have an orbital period of the order of a thousand years.
:
: Ok, so it is mere serendipity, there is nothing special about the stars
: or about their relationship, the only link is a line of three points the
: observer happens to be on. It would be strange indeed if such
: a relation did NOT exist given the vast number of stars available.
:
: You're overlooking a few things here....
:
: An optical pair, where the two unrelated stars just happen to be nearly
: along the same line of sight as seen from us, will almost certainly have
: both different distances and different proper motions. Which means the
: two stars will have different parallaxes as well as, relative to one
: another, a quite noticeable motion.

Any pair of stars will meet that criterion. What's so special
about being nearly on the same line-of-sight?

: The two pairs of Epsilon Lyrae are both, as far as we can tell, at the
: same distance. They also share the same proper motion relative to
: the background of fainter stars. It is extremely unlikely that this
: is due to serendipity - it's vastly more likely that it's because the
: two pairs are gravitationally bound to one another.

Two geostationary satellites are gravitationally bound to
the Earth, just as Sol is gravitationally bound to the Milky Way.
Are you claiming the satellites are gravitationally bound to
each other as far as you can tell?


:
: You accepted that Proxima Centauri is a physical member of the Alfa
: Centauri system, even though it resides 3 degrees away from the
: Alfa Centauri A+B pair. The reason Proxima is considered a physical
: member of this system is that it resides at nearly the same distance
: (in this case somewhat closer: 4.2 ly compared to 4.3 ly for the A+B
: pair) *and* that Proxima shares the proper motion of the A+B pair.
: If Proxima would have a quite different proper motion compared to
: the Alfa Centauri A+B pair, then Proxima's velocity relative to
: the A+B pair would exced the escape velocity, and Proxima would then
: not be a physical member of that system, but merely a star which happened
: to pass by.
:
: So the absence of detectable relative motion of the two pairs in
: Epsilon Lyrae is a clear indication that the two pairs *are*
: gravitationally bound to one another, since the relative velocity
: then does not exceed the velocity of escape. Two stars passing
: near one another by chance almost always do so with a relative
: velocity much larger than some fraction of a kilometer per second.
: And if they initially happened to be very far apart *and* almost at
: rest relative to one another, then they would never get close to one
: another - right?

If and only if geostationary satellites are gravitationally bound to each
other - right?


:
:
: : : The easier pair Alfa Capricorni, with the two components some 7 arc
: : minutes
: : : from one another, is an optical pair though.
: :
: : And so of no significance other than serendipity.
: : Oh look, here are two stars only 7 arc minutes apart, it must be an
: : optical double.
: : Oh look, here is the sun. It must be daytime.
: :
: : You can use Epsilon Lyrae and Alfa Capricorni as two good examples of
: : how to distinguish an optical pair from a physical pair: the relative
: motion
: : in the wide pair of Epsilon Lyrae is too small to be detectable for us,
: : but in Alfa Capricorni the relative motion is quite obvious.
:
: Part of my original post was to point out that optical pairs are of
: no particular interest to science. Where there is relative motion we
: have reason to investigate a relationship, and the closer the pair are
: the faster that motion will be. If you have no motion then it is unlikely
: that you have a binary.
:
: I strongly disagree with you here. A very wide binary with a period
: of a million years or so will have undetectable motion to us at our
: present state of astrometric measurements. In time we will of course
: also be able to detect also the very slow relative motion of these pairs,
: but we're not there yet.

If the system isn't a binary, then the question whether it's a binary
or not has already been answered,
ELSE

If the system IS binary, then the question whether it's binary
or not hasn't been answered.

What is the criteria for determining a binary?



:
: A very wide pair with an easily detectable relative motion will not be
: a binary, for one simple reason: even if the stars are close to one
: another in space, their relative velocities will exceed their mutual
: excape velocity. Therefore, after their close encounter they will
: wander away from one another into space, and not orbit one another in
: a closed orbit.
:
: A close binary will of course have a fast motion, here we agree. But
: we were discussing wide pairs he binaries resolvable with the naked
: eye. That excludes close binaries.

No no, we are discussing "can you name even one binary system
which isn't binary? g", to which I replied yes.
I'm still waiting for a yes/no response to

A binary system is only a binary if
a) it has two stars.
b) the stars are orbiting a common barycentre.
c) it can be resolved into two stars OR the velocity
of at least one of the pair can be measured spectroscopically.
The wild conjecture of an 18-year-old kid isn't sufficient
evidence for finding a binary system.
Do you agree?

: Of course you could be looking at the
: plane of the orbit face-on, but if the system is eclipsing then
: you have to be looking at it edge-on or nearly so and the motion
: easily detectable, particularly if the so-called binary has a short
: period measured in hours rather than years.
:
: ....and such a binary won't be resolvab with the naked eye either....

Exactly, so how do you determine a binary?

"Richard Tobin" wrote in message
...
: In article ,
: Androcles wrote:
: Meaningless drivel to be given as much weight as
: Kelleher's nonsense or any other crackpot's silly ideas.
:
: Mr Pot, meet Mr Kettle.
:
: -- Richard

Hello Mr. Kettle. Do you have any more meaningless drivel to
be given as much weight as Kelleher's nonsense or any other
crackpot's silly ideas?

On Dec 7, 5:36 pm, "Androcles" wrote:
"Richard Tobin" wrote in message

...
: In article , : Androcles wrote:

: Meaningless drivel to be given as much weight as
: Kelleher's nonsense or any other crackpot's silly ideas.
:
: Mr Pot, meet Mr Kettle.
:
: -- Richard

Hello Mr. Kettle. Do you have any more meaningless drivel to
be given as much weight as Kelleher's nonsense or any other
crackpot's silly ideas?

Richard is what you get when you think you can outwait a participant
who actually has something to say.

I watched the systematic destruction of Western astronomy,at least
temporarily,through the maneuvering of a pair of numbskulls (Newton/
Flamsteed) ,one no wiser to each others errors but nonetheless
creating the astrological framework by which you ,Richard and the rest
of you operate.

You lot are finished,the importance of meshing climate studies with
the accurate view of the motions of the Earth outweigh you exotic
concerns and useless sweeping staements about the Universe using the
non geometric approach of equations.

Geometry gets its revenge