The weather has been pointed out for weeks, but the spring equinox will finally arrive in the Chicago region this week.
The equinocium marks the moment when the sun crosses the equator from the southern hemisphere to the northern hemisphere and makes the days longer and continues the march towards summer.
When is the exact moment when spring officially begins, at least from astronomical perspective?
When does spring start officially?
According to NASA, the exact moment of the spring equinox will take place on Thursday at 4:01 a.m.
While conventional wisdom is that the first spring day marks 12 hours of daylight and 12 hours night, this is not exactly true. Since the earth is not a perfect sphere and the earth rotates in different widths at different speeds, the timing of sunrise and sunset does not fit perfectly with the 12-and-12 split at the date of the equinoctos.
For the area of Chicago, the date marks the date on which we go over 12 hours of daylight for the first time since September 24th. On the date of the Equinox, the city receives 12 hours and 10 minutes of daylight, and this daylight will continue to increase until the summer solstice in June.
When is the summer solstice?
According to NASA, the summer solstice, the longest day of the year in the northern hemisphere, will take place on Friday, June 20, at 9:42 p.m. with a central time.
