Natsue Morino

She is a character depicted in a flashback in Chapter 20 of the original manga's Volume 2 (Episode 6 of the anime adaptation). She is the grandmother of Mari Morino. She has a dream of owning land on the Moon and building her own grave there. She shared this dream with a young Mari Morino, which became the catalyst for Mari's interest in astronomy. At the point in the story when this topic is mentioned, the grandmother is alive and well.