The japanese bookEdit
The Book found in the second episode inside the school building is labeled 現代文 (Gendaibun / Modern Literature).
We instinctively followed Kyoko that ran out of the music room. Without thinking, our bodies moved on their own and we were unable to stop. Holding tight to the music instrument, we desperately ran down the light flooded, dazzling staircase. This way, it looked like we could lose sight of Kyoko forever, which scared us. The skirt(s) shook without as much as making a faint rustling sound. If we were to be found by a teacher, he would surely get angry. But that moment, it made no difference. That's because we too have things we should never lose.
Japanese original as taken from http://www31.atwiki.jp/sorawoto/pages/32.html
理屈ではなく、体が先に動き出して止めることができなかった。 楽器を握り締めて、光溢れる眩しい階段を必死で駆け下りる。 このままではキョウコを永遠に見失ってしまいそうで怖かったのかもしれない。 スカートがばさばさと音を立ててはしたなくゆれる。 先生に見つかったらきっと怒られる。 でも今はそんなことはどうでもよかった。 それよりも、私たちには失ってはいけないものがあるのだから。
The text seems to be a normal slice of life novel. However without the rest of the text it is hard to understand the actual subject of the text.
The title could mean the yearning for space travel.
Although, I think the japanese might have certain legends or stories regarding Spica (as with the summer triangle, the stars they refer to as Hikoboshi and Orihime)
The rest of the text is hard to read, as some words are blanked out or the page is cut off by the screen in mid sentence.
I'll try to translate the rest at least partially, though