Ask HN: How do you keep track of events like SpaceX's Crew Dragon launch?

This is the kind of event I enjoy watching live, yet I completely missed it until I heard about it on the evening news. Thankfully I'll still be able to witness the docking part of it in a few minutes.

I know I could probably find a calendar of all SpaceX's missions, but what about other types of events, such as "AlphaGo versus Lee Sedol"? Is there any calendar that aggregates all events that could be considered as humanity milestones?