Factual error: In the subplot on earth, the heroes' family members are trying to outrun the falling moon's gravity that's sucking everything into the air. So, naturally they duck into a barn, because, of course, gravity can't affect you behind a wall. And sure enough, behind the wall, they're suddenly safe.
Factual error: The satellite phones don't work as they should. They're somehow still able to use them to communicate after the moon has got close enough to the earth to cause enough damage to the satellite network that it'd no longer function, and can also make and receive calls while under tons of rock.