Consider these cosmic phenomena: 1. Black holes emit X-rays directly from their event horizon. 2. Pulsars are rapidly rotating neutron stars. Which of the above is/are correct?
Statement 2 only
Statement 1: The event horizon of a black hole is the boundary beyond which nothing — not even light — can escape. By definition, no electromagnetic radiation (including X-rays) can be emitted from inside or directly at the event horizon. The X-rays observed from black-hole systems actually come from outside the event horizon — from the extremely hot, infalling matter in the accretion disc as it spirals in. Incorrect.
Statement 2: A pulsar is a highly magnetised, rapidly rotating neutron star that emits beams of electromagnetic radiation from its magnetic poles. As the star rotates, the beam sweeps past Earth and is observed as regular pulses (hence the name). Discovered in 1967 by Jocelyn Bell Burnell and Antony Hewish. Correct.
Hence, only Statement 2 is correct. The answer is option B.
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