I feel like I'm not going to be able to say a whole lot about this book, because while I liked it - really liked it, was on the edge of my seat reading it, got kinda misty-eyed at the end - a lot its effectiveness came from the fact that I knew very little about it going in. I didn't even know which genre it would settle on! Gritty grimdark post-apocalyptic? Space adventure? Bloodless chronicle of the end of the world? A Melancholia-esque fatalistic drama? I had no goddamn clue even 90% of the way into book, and because of that, everything was more tense, the dangers more real. I don't want to go into detail about this one because I think "clueless" makes for the optimal reading experience. 
 I will say that I liked this book a lot. The protagonist, Denise, was a compelling character, and I felt her family plight on a fuckin' spiritual level. Her arc is thoughtful and...and a bunch of other things I can't say without ruining it. Spoiler tag? Spoiler tag. 
 (view spoiler)["Hopeful" is what I wanted to say, and it's what I liked most about this book. On the Edge of Gone is an optimistic depiction of the most depressing situation a person could ever have to deal with. I mean "comet apocalypse" is a fucking nightmare just to think about. You're staring down the barrel of extinction, the planet is done for, there's no way you can save everyone, and some people have an even worse chance than others. Even the ones who do manage to survive might never see their loved ones again, and also ALL OF THE DEAD ANIMALS SOB. 
 But unlike literally every other apocalypse book I've ever read - which take a catastrophe use it as an excuse to demonstrate the "true nature of humanity" i.e. people doing TERRIBLE things to one another in the name of survival - On the Edge of Gone has faith. Not like, religious faith, but faith in humanity and its ability face the end of everything with dignity and compassion. 
 I can see where this might stray into "unbelievable" territory for some, but I loved it. I was surprised and thoroughly gratified every time a character chose to be kind, and not murderous. 
 So, hopeful. Denise finding her place, finding her people, finding her family. Humanity banding together to fight for survival instead of competing for it. The generation ship agreeing to stay in orbit and support the ones left behind instead of abandoning them to start over somewhere new. It's an aspirational resolution, and I'm cool with that. Write the world you want to see and whatnot. Plus, it was still REALLY emotionally effective. Turns out, you don't have to kill everyone to make your readers feel things! (hide spoiler)] 
 Also, this book was diverse as fuck. We've got gay characters, trans characters, black and brown characters, a neurodivergent protagonist!!, and I thought they managed to effectively walk that fine line between homogenization and stereotype. Everyone was all allowed to be a full and participating character without having their differences/identities/marginalizations erased. And Denise! I'm not an expert on autism, but Denise was a boss-ass heroine and her perspective, struggles, and thought processes felt real. I found an article in which Corinne Duyvis talks about her goals and experiences in writing Denise (suitably un-spoilery), and fwiw, I think she accomplished those goals beautifully. 
 So yeah I really liked this one. Don't let anyone tell you anything about anything, just get the book and read it. And don't forget the tissues. 
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