C51 The Immortal Emperor's Conspiracy(2)

He had observed the sunspot many times and had discovered that there was a huge shadow within it. In general, the sun that had existed for hundreds of millions of years was rapidly aging. If nothing can stop this accelerated aging, the sun will explode and die soon.

From a human's point of view, "not too long ago" was, of course, in the order of hundreds of thousands of years