Characteristics of Galaxies: Spiral, Elliptical, Irregular

Analyze characteristics of galaxies.

Describe two to four characteristics of the three major types of galaxies. Compare and Contrast the size, composition, structure, and history of at least two specific galaxies. Describe how the characteristics of these galaxies contributed to the Hubble sequence. Consider the validity of the Hubble Sequence in modern astronomy. What observations contradict the theory of galactic evolution? What observations support the theory of galactic evolution?