[Atomic-S (OP)]

If the sun's equator rotates at a different rate than its poles, how long does a day last on the sun?

[yor_on]

SpaceMath. And it depends on from where you define your point of observation naturally. As the sun is a gas, well it is? it have this weird ability to act like a, ah, gas?

[syhprum]

Relative to the remote stars the rotation period on the equator is about 25 days while close to the poles it is 36 days.

[Atomic-S (OP)]

And it depends on from where you define your point of observation naturally.

Well, if you observe it on the sun, then from that viewpoint the sun never sets. Hence, the length of the day must be equal to the lifetime of the sun.