Hogwarts's (Hogwarts is Harry Potter's school) motto is "Draco Dormiens Nunquam Titillandus" which means "Never tickle a sleeping dragon".
I would say Harry's favorite place is Hogwarts because it was his first real home.
Nowadays term 'alma mater' doesn't refer to a person, but a school, so it would be Hogwarts.
The "school for magic" in Harry Potter is Hogwarts School of Witchcraft and Wizardry. There are four houses and each one bears the name of the four founders of Hogwarts, respectively: Gryffindor, Hufflepuff, Ravenclaw, and Slytherin.
constellations
If you mean Hogwarts, no one know, except for the fact that it's in Europe.
Harry Potter went to Hogwarts.
Severus Snape He had known Lily before they both went to Hogwarts
Harry Potter's parents, James Potter and Lily Evans, first met on the Hogwarts Express during their first year at Hogwarts School of Witchcraft and Wizardry in the 1970s. They became friends and later fell in love during their time at Hogwarts. Their relationship blossomed as they navigated their school years together, ultimately leading to their marriage before the events of the series.
Dumbledore
The death of his parents, his entrance at Hogwarts and his ultimate victory over Lord Voldemort
Hogwarts