What is the speed of gravity?

Infinite, instantaneous, no speed.

Science told you gravity speed is light speed 3 x 10^8 m/s. Which is mistaken.

If gravity is not instantaneous, since planets are orbiting, gravity will be delay all the time, no planet can have stable orbit.

Gravity is inherited force between masses, it is coexisted, indestructible, immortal, always there. Therefore gravity is instantaneous.

Put 1 electron and 1 proton at R distance, the attraction force is F=Ke x pq/R^2.

That force has no speed, that force is always there. Force don't travel, force don't move from matter to matter.

Electron and proton don't emit forcetrons to each other to attract each other.

Just like gravity is always attracting Sun and earth, they don't emit gravitons to each other.

If the Sun has a quake, all planets will simultaneously sense the gravity wave.

Detected gravity wave from 1.3 billion years ago is impossible. All matter and energy, all universe is existing at forever ongoing now.