Happy Chinese New Year! Here is an explanation of a solar year.
Today, Thursday February 19th, 2015, is the first day of the Chinese year of the Goat.
The Chinese year varies based on the Lunar year which is about 354.37 days, or twelve moon cycles with the intercalation (timekeeping) extra 13th month added every 2-3 years.
Interestingly, the Islamic New Year is purely lunar without intercalation and so the months bear no relation to the seasons.
Now, we all learned that a calendar year is 365 days with an extra day every 4 years (leap year)
But there are two other kinds of solar years: tropical and sidereal.