The hole of the planet has a diameter of 4000 miles and the overall radius is 8000 miles. The atmosphere is a cloud surrounding the whole planet.

Inside edge - the part of the planet closest to the axis of rotation.

Outside edge - the part of the planet farthest from the axis of rotation.

Questions:

Is it practical to fire a cannon across the hole? Would it be possible to see the target? Or would 4000 miles of air make visibility too low?

How much fuel would it take to launch a 50 ton spaceship from the inside edge of the planet to the center of the hole? How about the fuel required to launch the spaceship into equitorial orbit from the outer edge? Would an equitorial/near-equitorial orbit be stable? What would the path of a polar orbit look like? How about an orbit through the hole?

Would it be practical to launch a starship through the hole? How much of a gravity assist would there be?

Would Issac Newton have discovered his theory of Universal Gravitation? Or would the variable gravity and apparent slope of the surface have made it too difficult?

What would the seasons be like if the planet had an axial inclination of 15 degrees? Would polar icecaps form? Would oceans be stable, or would they flow to the center of the hole?

What would the wind flow be like? The wind flow is strong enough to keep water from forming a ball at the center of the hole. What would the rainfall pattern look like?