Premise: Hubble is helping astronomers precisely calculate the age of the universe by providing accurate distances to galaxies, an important prerequisite for calculating age. Hubble measures the distances to neighboring galaxies by finding accurate "milepost markers," a special class of pulsating star called Cepheid variables. These, in turn, are being used to calibrate more remote milepost markers.
Hypothesis: Hubble discovers black holes.
Label: UNKNOWN