X-ray emissions from the Crab Pulsar are more intense during giant radio pulses (GRPs), researchers report. The new findings provide constraints on the mechanisms underlying GRPs and may provide insights into other transient radio phenomena observed throughout the Universe. Pulsars, or rapidly spinning neutron stars, emit pulses of electromagnetic radiation from their magnetospheres and are observed from Earth as regular sequences of radio pulses. Most radio pulses from these distant objects are of a consistent intensity. Occasionally, however, sporadic and short-lived bursts from these sources are observed hundreds to thousands of times brighter than normal. What causes these unpredictable bursts, also known as GRPs, is unknown. Teruaki Enoto and colleagues observed the Crab Pulsar using both X-ray and radio telescopes and found that X-ray emission during GRPs is slightly brighter than during normal pulses. By comparing the radio and X-ray enhancements, Enoto et al. found that the total emitted energy from GRPs is tens to hundreds of times higher than previously known. According to the authors, the findings also help constrain extragalactic fast radio bursts (FRBs), whose mysterious origins remain unknown.