two sentences

[mengta]

Sunspots are visible as dark spots on the surface of the Sun but have never been sighted on the Sun's poles or equator.

Sunspots appear on the surface of the Sun as dark spots although never sighted on the Sun's poles or equator.

the first sentence is the original sentence.
i just can't figure out what's the matter with the second sentence.

thanks

[Tdol]

Although never sighted on the Sun's poles or equator, sunspots appear on the surface of the Sun as dark spots.

Or I'd say 'although they are never sighted' in you version.

[curmudgeon]

To appear and to be sighted can mean different things. Appear could mean occur, but sighted means they have been seen.

Actually there is nothing wrong with the second sentence as the meaning is clear. It might be better to say;
Sunspots appear on the surface of the Sun as dark spots but have never been sighted on the Sun's poles or equator.