ABANDONED. about a boy who looks older than he is and travels to space with his friend, both of them and other kids getting stuck there

[starboy]

i read this book around 2015-2017. the cover was a boy standing there and a cresent moon and two stars making a smiley face

[Kris]

Syd, what's the genre (which we need to add to the topic header/title) - e.g., for kids or teens, picture book or children's novel, science fiction, adventure?

[Becca]

Cosmic by Frank Cottrell Boyce. I think this is the cover you remember:

[Kris]

No response, moving to Abandoned folder.

Syd (OP) was last active on the site in September 2020.