Assertion: flare | /r/HasAspect | hard spectrum
Facets:
Source sentences:
text: The most powerful flare which also had a hard spectrum that has been observed instrumentally took place in February 1956 (the beginning of nuclear testing obscures any possible effects in the 14C record); it has been estimated that if a single flare were responsible for the AD 774/5 event it would need to be 25-50 times more powerful than this.