What did walking inside an active volcanic crater have to do with your current occupation?

Question: What did walking inside an active volcanic crater have to do with your current occupation?
- Keywords:
  crater,
  volcano
Asked by Big_C to Darren on 9 Nov 2016.
- Darren Rhodes answered on 9 Nov 2016:
  
  I went there on a trip to Japan. I gave a talk at the University of Tokyo, but had some spare time after it to go and ‘geek-out’ and check out some cool science stuff. No real connection – but just natural love of science and to be curious.

Question: What did walking inside an active volcanic crater have to do with your current occupation?