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<h1><span class="header-section-number">Chapter 4</span> Data Visualization<a href="data-visualization.html#data-visualization" class="anchor-section" aria-label="Anchor link to header"></a></h1>
<p>On January 28, 1986, the Space Shuttle Challenger exploded 73 seconds after takeoff, killing all 7 of the astronauts on board. As when any such disaster occurs, there was an official investigation into the cause of the accident, which found that an O-ring connecting two sections of the solid rocket b