Question: Can the earth expand?

Jess Wade answered on 22 Jun 2015:

Hey GeNiUS- great question-

The world is indeed constantly changing and growing and contracting. Mountains form due to big physical stress when tectonic plates collide (the same things that cause earthquakes). Valleys and canyons are forming due to erosions. There are lots of weird science stories out there, saying that continents moving makes the world bigger, but no one really believes it.
The atmosphere actually breathes, expanding and contracting because of fluctuations in radiation from the sun. We talk about something called the ‘solar cycle’, where the sun changes its radiation every 11 years or so. These cause things like super fast solar winds towards earth, which cause our atmosphere to heat up and expand, then cool down and contract.