Let's say a star is formed a thousand light years from earth. How long before the gravity from the newly formed star reaches earth? IOW, how fast does gravity travel?
Gravity is currently thought to travel at the speed of light.
Gravity itself is a field. So travel doesn’t apply. It’s like saying how fast is the ocean between SF and Tokyo. However, gravity waves, according to general relativity (and some pretty strong evidence), travel at exactly the speed of light.