sun, moon and earth are in a straight line

-happens 2x a month

-creates really high tide and really low tide

-sun and moon are at a right angle

 -happens 2x a month

-creates a lower high tide and a higher low tide

-each year has 365 1/4 days

-every 4 years we gain another whole day

-new moon

-waxing crescent

-first quarter

-waxing gibbous

-full moon

--waning gibbous

-third quarter

-waning crescent