Hirahara Ayaka's song "Jupiter" that Chihaya did a really great cover of is from the "Jupiter" section of Holst's The Planets. Holst later adapted the original version to be used as a hymn, which has had a handful of re-lyricizing over the years. It's a really nice tune.
https://www.youtube.com/watch?v=rFx01mYCw_Yhttps://www.youtube.com/watch?v=Isic2Z2e2xs&t=1295shttps://www.youtube.com/watch?v=PnnQpC9oLxU 