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Representations"> next » </a> </li> <li class="right"> <a href="formatting.html" title="Formatting Coordinate Strings"> « previous </a> | </li> <li> <a href="../index.html">Astropy v0.2.4</a> » </li> <li><a href="index.html" accesskey="U">Astronomical Coordinate Systems (<tt class="docutils literal"><span class="pre">astropy.coordinates</span></tt>)</a> »</li> <li>Separations</li> </ul> </div> <div class="document"> <div class="documentwrapper"> <div class="bodywrapper"> <div class="body"> <div class="section" id="separations"> <h1>Separations<a class="headerlink" href="#separations" title="Permalink to this headline">ΒΆ</a></h1> <p>The on-sky separation is easily computed with the <tt class="xref py py-obj docutils literal"><span class="pre">separation</span></tt> method, which computes the great-circle distance (<em>not</em> the small-angle approximation):</p> <div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">c1</span> <span class="o">=</span> <span class="n">ICRSCoordinates</span><span class="p">(</span><span class="s">'5h23m34.5s -69d45m22s'</span><span class="p">)</span> <span class="gp">>>> </span><span class="n">c2</span> <span class="o">=</span> <span class="n">ICRSCoordinates</span><span class="p">(</span><span class="s">'0h52m44.8s -72d49m43s'</span><span class="p">)</span> <span class="gp">>>> </span><span class="n">sep</span> <span class="o">=</span> <span class="n">c1</span><span class="o">.</span><span class="n">separation</span><span class="p">(</span><span class="n">c2</span><span class="p">)</span> <span class="gp">>>> </span><span class="n">sep</span> <span class="go"><AngularSeparation 20.74612 deg></span> </pre></div> </div> <p>The <a class="reference internal" href="../_generated/astropy.coordinates.angles.AngularSeparation.html#astropy.coordinates.angles.AngularSeparation" title="astropy.coordinates.angles.AngularSeparation"><tt class="xref py py-obj docutils literal"><span class="pre">AngularSeparation</span></tt></a> object is a subclass of <a class="reference internal" href="../_generated/astropy.coordinates.angles.Angle.html#astropy.coordinates.angles.Angle" title="astropy.coordinates.angles.Angle"><tt class="xref py py-obj docutils literal"><span class="pre">Angle</span></tt></a>, so it can be accessed in the same ways, along with a few additions:</p> <div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">sep</span><span class="o">.</span><span class="n">radians</span> <span class="go">0.36208807374669766</span> <span class="gp">>>> </span><span class="n">sep</span><span class="o">.</span><span class="n">hours</span> <span class="go">1.383074562513832</span> <span class="gp">>>> </span><span class="n">sep</span><span class="o">.</span><span class="n">arcmins</span> <span class="go">1244.7671062624488</span> <span class="gp">>>> </span><span class="n">sep</span><span class="o">.</span><span class="n">arcsecs</span> <span class="go">74686.02637574692</span> </pre></div> </div> </div> </div> </div> </div> <div class="sphinxsidebar"> <div class="sphinxsidebarwrapper"><h3>Page Contents</h3> <ul> <li><a class="reference internal" href="#">Separations</a></li> </ul> </div> </div> <div class="clearer"></div> </div> <footer class="footer"> <p class="pull-right"> <a href="http://github.com/astropy/astropy/tree/v0.2.4/docs/coordinates/separations.rst">Edit This Page on Github</a> <a href="../_sources/coordinates/separations.txt" rel="nofollow">Page Source</a> <a href="#">Back to Top</a></p> <p> © Copyright 2011-2013, The Astropy Developers.<br/> Created using <a href="http://sphinx.pocoo.org/">Sphinx</a> 1.1.3. 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