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#FaveAstroPlot : Pulsars

Here's a tweet showing the radio pulses observed from a pulsar, in fact the first radio pulsar discovered by Jocelyn Bell Burnell, for which her thesis adviser got a Nobel prize (which he didn't share with her but that's a whole different story). There's also a fairly interesting story behind the image itself that can be found here.

Firstly, put yourself in a time and age when radio astronomy was still nascent and people were just scratching the surface of various radio sources. Also, this wasn't the era of milli-arcsecond resolution radio astronomy but it was the era of single dish-arcminute resolution astronomy. Radio astronomers used to perform lunar occultations to reduce the uncertainty of an astronomical object's position. Secondly, this was before digital devices were ubiquitous for recording and displaying the radio signals. There were analog chart recorders which used to plot the total strength of the radio signal that the telescope receives on ginormous pieces of chart paper (an example can be found here).

Jocelyn Bell Burnell, then a graduate student, was performing some radio observations when she noticed regularly spaced peaks in her signal. of extraterrestrial origin and without precedent, the student-guide team chose to not publish the data but to perform more observations in hopes of either disproving the previous observation as man made noise or prove that there were more such radio astronomical objects. Well, the rest is history and pulsars are a really interesting part of radio astronomy and astrophysics in general. They are also used to test the general theory of relativity but we'll get to that in a later part.

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