Multiple MatchingExercise 63 of 70

Pulsars, the rapidly rotating magnetised remnants of massive stars that have undergone gravitational collapse, emit collimated beams of electromagnetic radiation from their magnetic poles - beams that, owing to the misalignment of the magnetic and rotational axes, sweep across the observer's line of sight with a…

• Which stellar remnant was initially mistaken by its discoverers for a possible signal of intelligent extraterrestrial origin?
• Which stellar remnant's interior is theorised to contain phases of matter so exotic that they remain beyond the reach of current observational technology?