[liberallarry]

If it is seconds of time there's something seriously wrong with my understanding. I would think the Black Hole is constantly radiating both X-Rays and visible light - so how is this time differential measured?

[Physicist]

Blobs of matter fall into the black hole at irregular intervals. The luminosity of a black hole is not constant; it flares up as the clumps fall inward. The smaller the black hole, the shorter the interval over which the luminosity varies. In this case, it takes just seconds for this particular black hole to eat a meal.