I didn’t know either so I looked it up, apparently it was the first detected radio pulsar, briefly thought to be an extra terrestrial transmission…and later used on Joy Division album cover: https://en.m.wikipedia.org/wiki/PSR_B1919%2B21
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I didn’t know either so I looked it up, apparently it was the first detected radio pulsar, briefly thought to be an extra terrestrial transmission…and later used on Joy Division album cover: https://en.m.wikipedia.org/wiki/PSR_B1919%2B21