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<node id="1009330" title="Re^3: Irrational numbers" created="2012-12-18 05:13:19" updated="2012-12-18 05:13:19">
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<author id="171588">
BrowserUk</author>
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&lt;blockquote&gt;&lt;i&gt;Say you have a spaceship in a circular orbit around the sun ... and request a result with a millimeter precision.&lt;/i&gt;&lt;/blockquote&gt;

&lt;p&gt;Sorry, but your misunderstandings are legion.

&lt;P&gt;It would be impossible to pre-calculate such an encounter, regardless of the precision of the calculations. 

&lt;P&gt;The gravitational field of the Sun is neither uniform nor constant; and we do not yet have, and never will have, an accurate mapping of it; nor any way to produce one. 

&lt;P&gt;For a start, in order to produce such a map, it would be necessary to have an identifiable reference point or line, but the Sun's surface and its interior rotate at different speeds; and the surface rotates at different speeds relative to latitude, with the poles rotating almost 50% faster than the equator. The surface is constantly changing so there is no way to denote a fixed reference point. 

&lt;P&gt;In addition, solar radiation has a profound affect upon small craft in orbit around the Sun; and it is entirely unpredictable.

&lt;P&gt;These, and many other factors, are why all long distance space flights have in-transit correction burns built into them.  Not to correct for inaccuracies in precalculations; but rather to correct for the unknowable and unpredictable affects of gravitational perturbations and variable solar pressures.

&lt;p&gt;And that is why all docking maneuvers in space require either manual corrections or programmed, active corrections using vehicle to vehicle sensing during final approach.

&lt;p&gt;The polite assessment of your idea is that it is a solution looking for a problem to solve. If implemented, it would at best be, an unnecessary drain on computing resources; at worst, completely pointless.

&lt;div class="pmsig"&gt;&lt;div class="pmsig-171588"&gt;
&lt;hr /&gt;
&lt;font size=1 &gt;
&lt;div&gt;With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'&lt;/div&gt;
&lt;div&gt;Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.&lt;/div&gt;
&lt;div&gt;"Science is about questioning the status quo. Questioning authority". &lt;/div&gt;
&lt;div&gt;In the absence of evidence, opinion is indistinguishable from prejudice.
&lt;p align=right&gt; [http://thebottomline.cpaaustralia.com.au/|RIP Neil Armstrong]&lt;/p&gt;&lt;/div&gt;
&lt;/font&gt;

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