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src/resources/help_en.html

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 <h3>Short description:</h3>
-This is an interactive animation of a binary star system with a pulsar &ndash; a rapidly rotating neutron start with a strong magnetic field, emitting two focussed beams of radio waves (yellow cones) along its magnetic axis.<br>
+This is an interactive animation of a binary star system with a pulsar &ndash; a rapidly rotating neutron star with a strong magnetic field, emitting two focussed beams of radio waves (yellow cones) along its magnetic axis.<br>
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 The diagram below the animation shows the radio pulses an observer (red line) can measure during one rotation of the pulsar &ndash; the observer measures a signal whenever he is grazed by a bundle of radiation.<br>
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