After a long, cold, [and here in San Francisco very rainy] winter, Spring is finally here. This week we celebrated the Vernal Equinox, which marks the end of Winter and beginning of Spring. The official Vernal Equinox (also called the Spring Equinox) was on March 20th this year, but depending on the year it can be on the 19th or 21st as well. In addition to marking the first day of Spring, it also marks the day when days and nights are the same length — 12 hours each (equinox literally means "equal night" in Latin). Get up to date on the Vernal Equinox and the rest of what makes seasons seasons, on Quizlet this week.