(WKBN) — The month of September always brings changes. Students come back from summer break, football starts back, and even the temperature starts to become cooler.

Another change that becomes evident is the difference in sunrise and sunset times compared to summer. That is why Wednesday will be different.

The sun will not rise until 7 a.m. Wednesday, which has not occurred since April 4, 2023.

Interestingly, due to the time change, the sun will rise before 7 a.m. again for a couple of days in November (November 5 and 6). However, after that, the sun will not rise before 7 a.m. again until February 28, 2024.

Here are some other important dates regarding the sunrise over the next few months:

  • Latest sunrise after time change: December 29, 2023, at 7:47 a.m.
  • Next sunrise before 7 a.m. (post time change): February 28, 2024
  • Next sunrise before 6 a.m.: May 20, 2024
  • Earliest sunrise of 2024: June 18 at 5:49 a.m.

The fall equinox is almost here

We are now only 11 days away from the fall equinox, which will occur on September 23 at 2:49 a.m. While the date is usually known, the definition of the equinox is not always well understood.

Until 1543, the general consensus was that the sun revolved around the planet Earth. This was the belief because the position of the sun moves in the sky throughout the day.

Some ancient scientists hypothesized that it was during this year that Nicolaus Copernicus developed the radical theory that the Earth actually revolves around the sun. He detailed his theory by illustrating the heliocentric model below.

The Copernicus heliocentric model of our solar system (Courtesy of NASA).

The heliocentric model was the answer for why there is daytime and nighttime. The Earth completes a rotation roughly every 24 hours causing periods of light and darkness throughout the world.

What this model does not answer is why there is a difference in daytime and nighttime throughout the year. The reason lies with the tilt of the Earth which has been reasonably well-understood since the ancient Greeks walked the Earth around 350 BCE.

The tilt of Earth is approximately 23.5°. The tilt in the Earth is the cause for Earth’s seasons, and it also causes the different sunrise and sunset times throughout the year.

Sunshine directly overhead oscillates between 23.5°N latitude (Tropic of Cancer) and 23.5°S latitude (Tropic of Capricorn). When the sun is directly over the Equator, this is called the Equinox. This occurs twice a year: once in the spring and once in the fall.

Explanation of why Earth has seasons (NASA).

The fall equinox occurs when the direct rays of sunlight are moving to the south as the northern hemisphere tilts away from the sun. The fall equinox marks the official end of astronomical summer and is the beginning of fall.

Get those jackets ready, because the fall temperatures will be here before you know it!