Different way to Witness

On Thursday I have a class called Introduction to Astronomy. We got on to the topic of how the moon was formed. The Big Bang Theory was talked about. While the teacher was talking about 13 billion years ago something just happen that caused all of this. She paused and one of my classmates phones started to "ring" the song "When I call on Jesus All Things Are Possible". The lady could not get the the phone quick enough so it went on for a while very loud. I thought what a witnessing tool.