Lunar New Year, Fat Tuesday, Ramadan and Lent occur around the same time this year

This Tuesday and Wednesday, four holidays from different cultures and religions overlap in a rare calendar year.

The celebrations of Fat Tuesday (Mardi Gras) and Lunar New Year both occur on Tuesday, Feb. 17. This won’t happen again until Feb. 13, 2029, according to the websites chinahighlights.com and mardigrasneworleans.com.

Ramadan is expected to start Tuesday evening, pending official confirmation, and Lent (Ash Wednesday) begins on Feb. 18. Last year, Ramadan and Lent began within a week of each other on Feb. 28 and March 5.

The holidays are all happening within two days this year because several long solar, lunar and lunisolar calendar cycles sync up.

Lunar New Year happens on the second new moon after winter solstice, which is also Fat Tuesday (Mardi Gras) — 47 days before Easter Sunday.

There are varying types of calendars.

The 365-day Gregorian calendar is a solar calendar, based on seasons as the Earth moves around the sun.

The Lunar New Year uses the lunisolar calendar, which is based on calculations of the sun and the moon. Chinese, Hindu and Hebrew calendars use this system, but with different variants.

The traditional Chinese calendar has years with 12 months and 353, 354 or 355 days, and leap years with 13 months and 383, 384 and 385 days, according to Royal Museums Greenwich.

So what are all of these holidays?

Fat Tuesday, or Mardi Gras, is the last day to feast on rich, fatty foods before the 40-day Lenten season starts the next day, on Ash Wednesday.

Ramadan is the ninth and holiest month in the Islamic calendar and a 29 to 30 day period of fasting, prayer, reflection and community.