gen-briefly-explain-the-lunar-versus-solar-calendar-and-one-comm-1775

Briefly explain the lunar versus solar calendar and one common misconception about it.

# Lunar vs. Solar Calendars **Solar calendars** are based on Earth's orbit around the Sun (approximately 365.24 days). They keep seasons aligned with specific months—like summer always occurring in June-August in the Northern Hemisphere. The Gregorian calendar we use today is solar. **Lunar calendars** are based on the Moon's phases (approximately 29.5 days per cycle). A purely lunar year has about 354 days, causing months to drift through the seasons over time. The Islamic calendar is purely lunar. **Lunisolar calendars** (like the Hebrew and Chinese calendars) use lunar months but add periodic leap months to stay synchronized with solar seasons. ## Common Misconception Many people think the **Chinese/Hebrew/Islamic calendars are all the same type**, calling them all "lunar calendars." In reality, the Islamic calendar is purely lunar (so Ramadan shifts seasons each year), while the Chinese and Hebrew calendars are *lunisolar* (their holidays stay roughly seasonal—Chinese New Year is always in late winter, Passover always in spring).