~galaxy-1
What is a galaxy?
What are some well-known galaxies?
What is the Milky Way?
What is the structure of all galaxies?
What is the timeline of knowledge about galaxies?
How are galaxies categorized?
What is the role of the brightest cluster galaxy in a cluster of galaxies?
What are the components of a spiral galaxy?
What were galaxies initially thought to be?
What are the characteristics of starburst galaxies?
What are some well-established named galaxies?
What are the three main types of galaxies?
What are current models of the formation of galaxies based on?
What is the dominant feature of cD galaxies?
Where does the word 'galaxy' come from?
