To put this in perspective:

Since the first hominids looked up at the stars, till literally yesterday, mankind had only one fundamental force to observe the universe with: electromagnetic waves, be it light, radio waves or infrared. From today, we have two. The other two remaining fundamental forces do not operate at astronomical scales.

Of course, we had LIGO before yesterday, but for me, the confirmation through electromagnetic wave observations is key. This is an historic day!