Astronomers Richard Lieu and Lloyd Hillman at the University of Alabama in Huntsville used this idea to look for speed distribution in light from galaxies billions of light-years away that were imaged by the Hubble Space Telescope. If all photons are traveling from the galaxy at the exact same speed then all the light waves will arrive in phase. When they pass through a telescope's aperture, they interact with each other to create a pattern of bright and dark rings called an Airy disk. However, if the speeds are even the tiniest bit off, the light is not in phase. These light waves align chaotically, and no pattern is formed. Lieu and Hillman suspected that slight differences in the speed of individual photons would cause their light waves to get out of sync over great distances, preventing the Airy disk from forming. Much to their surprise, the light was all in phase and an Airy disk appeared, implying that time is not quantized.