Definition of Assonance. Assonance is the repetition of a vowel sound or diphthong in non-rhyming words. To qualify as assonance, the words must be close enough for the repetition of the sound to be noticeable. Assonance is a common literary technique used in poetry and prose, and is widely found in English verse.
Nevertheless, scientists have been able to determine the probable age of the Solar System and to calculate an age for the Earth by assuming that the Earth and the rest of the solid bodies in the Solar System formed at the same time and are, therefore, of the same age.
Computer models allow us to predict how old a star of that mass must be to be at that juncture of its life, and hence to estimate the age of the cluster. It is impossible to determine the age of a single star all by itself. The only real means we have to determine stellar ages is through the study of star clusters.