Re: We do not know the distance of stars

mccoy@xxxxxxxxxx wrote in news:1144281910.727308.19190
@g10g2000cwb.googlegroups.com:

Any simpleton who knows basic surveying techniques knows that
triangulation is used in surveying and, indeed in supposed
determination of star distances. Simply put we do not know how far
stars are.

Any simpleton knows that triangulation is not the ONLY means of measuring
a distance.

In land surveying multiple angles are often taken to determine
locations. Such determination is done by numerous locations in and
around the distant object in question. We cannot do that with stars.

Actually, we CAN, moron. We're orbiting our sun every year.

We're on this side of the universe and there is no possible way to get
to the other side.

That's true, but it's not necessary to get to the other side.

Additionally, consider this:

"In triangulation surveys, a great deal of attention was paid to the
geometric strength of figure of each control configuration (see table
A.15). Generally, an equilateral triangle is considered strong,
whereas triangles with small (less than 10 degrees) angles are
considered relatively weak. Trigonometric functions vary in precision
as the angle varies in magnitude."

This is because of measurement errors with respect to small angles. We
can measure small angles much more precisely with large astronomical
telescopes, especially when we measure them against the background of
much more distant objects.

[comment: astronomers calculate supposed distances based on triangles
that are less than 1 degrees angles]

Routinely and accurately, moron.

"The sines of amll angles (near zero), the cosines of large angles
(near 90degrees) angles are all relatively imprecise. That is, there
are relatively large changes in the values of the trigonometric
functions that result from relatively small changes in angular values."

This is simply a BIG FAT LIE. These trig functions can be calculated to
any desired degree of precision from converging series. More than 15
years ago I was calculating values like these to 10,000 decimal places on
a 386-20. It's trivial.

For example, the angular error in 5 seconds for the sine of 10 degrees
is 1/7300, whereas the angular error in 5 seconds for the sine of 20
degrees is 1/15000. and the angular error in 5 seconds for the sine of
80 degrees is 1/234000."

This is bull***. There is no such angular error. There are MEASUREMENT
errors, but these are nowadays in hundredths of seconds of arc. There
are NO significant errors in the trig functions.

"One can see that if sine or cosine functions are used in triangulation
to calculate the triangle side distances, care must be exercised that
the trigonometric fucntion itself isn't contributing errors to the
solution more significant than the specified surveying error limits."

"When all angles and distances are measured for each triangle, the
redundant measurements ensure an accurate solution, and the
configuration strength of figure becomes somewhat less important.
However, given the opportunity, most surveyors still prefer to use
well-balanced triangles and to avoid using the sine and tangent of
small angles and the cosine and tangent of large angles to compoute
control distances."

What follows is a series of computational problems that illustrate
error.

Concludes:

"The foregoing illustrates that the surveyor should either avoid using
weak angles in distance computations, or if weak angles must be used,
they should be measure more precisely than would normally be required.
Also illustrated here is the need for the surveyor to preanalyze the
proposed control survey configuration to determine optimal field
techniques and attendant precision. "

Surveying: Principles and Applications
Kavanah/Bird-1984

"...The strength of the figure is a function of:

"1. The geometric strength of the triangles that make up the network.
Ideally, the triangles should be equilateral"

[comment: impossible to get equilateral triangles for astronomical
work.]

Introduction to Surveying
Anderson/Mikhail 1985


Cute. Now you should go take a course in astrometrics. What works for
surveying will NOT work for astrometrics, of course, so it's not used.

But why are you in here peddling outright lies, SIR? What is your
motive? You are still under the influence of your pet devil, right?

--
Dave Oldridge+
ICQ 1800667

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