Discernment is right, its been considered a fabrication.
http://www.catholic.com/thisrock/1994/9406qq.asp
Interesting — the disclaimer at the top said that no endorsement had been made.
The post Dominick links to is hardly authoritative, but is much better than some nonsense I’ve seen. I actually got suckered into believing that Pope John Paul II was born during a solar eclipse because one source was normally very credible.