https://techcrunch.com/2018/05/22/watch-spacex-launch-the-grace-fo-and-iridium-next-satellites-here/

Today’s the day for SpaceX’s launch of Iridium’s NEXT communications satellites and a pair of twin birds from NASA that will monitor the fresh water on the surface of the Earth. You can watch the launch right here:

Liftoff is scheduled for 12:47 PM Pacific Time, so SpaceX’s live stream should fire up about 15 minutes ahead of that; NASA will also have its own updates, since it has skin in the game.