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<record version="1" id="990">
 <title>example converting ecliptic coordinates to rectangular coordinates</title>
 <name>ExampleConvertingEclipticCoordinatesToRectangularCoordinates</name>
 <created>2025-03-14 00:21:36</created>
 <modified>2025-03-14 00:21:36</modified>
 <type>Example</type>
<parent id="951">ecliptic coordinate system</parent>
 <creator id="1" name="bloftin"/>
 <modifier id="1" name="bloftin"/>
 <comment>added that article was generated by Grok</comment>
 <author id="1" name="bloftin"/>
 <classification>
	<category scheme="msc" code="95.10.-a"/>
 </classification>
 <related>
	<object name="EclipticCoordinateSystem"/>
 </related>
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 <content>Consider an object with ecliptic coordinates:
\begin{itemize}
    \item Longitude: \( l = 30^\circ \),
    \item Latitude: \( b = 15^\circ \),
    \item Distance: \( r = 1 \) AU.
\end{itemize}

The conversion to rectangular coordinates is given in ecliptic coordinate system:
\begin{align*}
    x &amp;= r \cos b \cos l, \\
    y &amp;= r \cos b \sin l, \\
    z &amp;= r \sin b.
\end{align*}

Convert to radians:
\[
l = 30^\circ = \frac{\pi}{6} \approx 0.5236, \quad b = 15^\circ = \frac{\pi}{12} \approx 0.2618.
\]

Compute:
\[
\cos b \approx 0.9659, \quad \sin b \approx 0.2588, \quad \cos l \approx 0.8660, \quad \sin l = 0.5000.
\]

Then:
\[
x = 1 \times 0.9659 \times 0.8660 \approx 0.8365,
\]
\[
y = 1 \times 0.9659 \times 0.5000 \approx 0.4830,
\]
\[
z = 1 \times 0.2588 \approx 0.2588.
\]

Thus, the rectangular coordinates are:
\[
(x, y, z) \approx (0.8365, 0.4830, 0.2588) \, \text{AU}.
\]</content>
</record>
