Answer: pulsars

AnswerCrossword Clue
PULSARSHighly magnetic celestial bodies
PULSARSAntony Hewish discovery of 1967
PULSARSFlashers in space
PULSARSRadio wave emitters
PULSARSWave-emitting celestial objects
PULSARSSome neutron stars
PULSARSOther senders from space.
PULSARSStars that exhibit the "lighthouse effect"
PULSARSRotating neutron stars
PULSARSCelestial objects that emit radio waves
PULSARSHeavenly bodies
PULSARSRadiation-emitting stars
PULSARSSmall, dense stars
PULSARSEmitters of cosmic rays
pulsarsPULSAR, a celestial source of radio waves
pulsarsa celestial source of pulsating electromagnetic radiation (as radio waves) characterized by a short relatively constant interval (as .033 second) between pulses that is held to be a rotating neutron star