It's a common misconception that Neptune's winds are driven solely by internal heat. While Neptune *does* have a surprisingly hot interior for its distance from the Sun, the primary driver of its incredibly strong winds is actually the planet's rapid rotation.

Here's how it works:

* Rapid Rotation: Neptune spins very fast, completing a rotation in just 16 hours. This rapid rotation creates a powerful Coriolis effect.

* Coriolis Effect: This effect causes moving objects (like air) to be deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. On Neptune, this creates massive, swirling jet streams, similar to the jet streams on Earth, but much stronger due to the planet's rapid rotation.

* Internal Heat: While not the primary driver, Neptune's internal heat does contribute to the winds. This heat is likely generated by gravitational pressure from the planet's core and from the slow "rain" of heavier elements like helium sinking towards the core.

So, to summarize:

* Neptune's incredibly fast winds are primarily driven by the planet's rapid rotation and the resulting Coriolis effect.

* Internal heat contributes to the energy driving the winds but is not the main factor.

It's also important to note that while Neptune's winds are incredibly powerful, they don't move as fast as 1000 mph. Estimates suggest speeds of around 600 mph, which is still incredibly fast.