SOLVED. YA book where the moon gets too close to the earth [s]

[Meryl]

I think the book was written like entries in a diary. After the moon gets too close (maybe an asteroid hit it?)it starts an apocalypse. One family stocks up on canned food and other supplies and this helps them survive for longer than most people.

[Kristina]

I love this book! It is Life As We Knew It.

[Meryl]

Yay - that's it - thanks! Solved!!