How long in earth time is one day on the sun?

Answer 1

That would depend on what you mean by a "day" on the sun. On earth it is nomally defined in terms of a cycle of light and dark but, since the sun is the source of day and night on earth, that definition would not work for the sun.

Another way of looking at it might be to consider how long the sun takes to rotate about its axis. Unlike the earth, though, the sun is not solid and does not rotate at the same rate all over. At its equator the sun rotates once every 24.5 days (approx) and that is probably the nearest to a straight answer that I can give.

Answer 2

That depends on what you'd call a 'day' on the sun.

If a day is one cycle of light and dark ... like it is for everything else in the solar system ... then

there's no such thing on the sun. The sun is the source of light in the solar system, so nowhere

on the sun ever gets dark.

On every planet including the earth, a 'day' is roughly the time it takes to spin on its axis. Even

that definition is hard to pin on the sun ... the sun isn't a solid body, so different parts of it spin

at different rates.

Depending on exactly where you look on the sun, the part you're looking at takes somewhere

between 25 and 36 earth days to make one complete revolution.