Assertion: astronomer's study | /r/HasProperty | expanding branch of astronomy
Facets:
value: rapidly
type: MANNER
Source sentences:
text: Powerful gamma rays can, however be detected by the large air showers they produce, and the study of cosmic rays is a rapidly expanding branch of astronomy.
text: Powerful gamma rays can, however be detected by the large air showers they produce, and the study of cosmic rays is a rapidly expanding branch of astronomy.