On the first night of 2018 you might look up at the sky and say, "Wow, the moon looks huge tonight. Well the reason why is, it is the first "supermoon" of 2018. A supermoon happens when the moon becomes full on the same day it reaches the point in the moons elliptical orbit closest to the earth.

During this time the moon looks way larger and brighter than usual. NASA says this happens around every 13 months. If you miss the supermoon on January 1st do not worry. Another one will happen again on January 31st.

NASA notes some people refer to this second full moon in a single month a "Blue Supermoon". These occur about every two and half years.