The end of our darkest days is near — nearer, in fact, than you may have been lead to believe.

As of Friday, Nov. 30, the sun is setting at 4:11 p.m., the earliest it will set on the Vineyard for the rest of the year. Sunsets will start getting later in the afternoon beginning on Dec. 15, when the sun will set at 4:12 p.m.

Why is this happening prior to the Winter Solstice? Contrary to those who think the shortest day of the year is Dec. 21, there is a difference between the concept of the shortest day of the year and the times associated with sunrises and sunsets here in New England and in other parts of the globe.

Sunset and sunrise is calculated on the basis of when the sun crosses the horizon — the moment it disappears at sunset and the moment it first appears at sunrise. Were our Earth to be without an atmosphere, one could say Dec. 21 is the shortest day of the year. But the Earth’s atmosphere is a lens that clings to the image of the sun, playing with our perception of it. The sun rises before it really appears on our horizon and disappears at sunset later than when the sun actually sets.

At our latitude, the skewed perception is even more pronounced than for those living at the Equator. That perception is calculated into our sunrise and sunset times.

While sunset will be no earlier than 4:11 p.m. for the next two weeks, the sun will continue to rise later in the morning until Dec. 28, when sunrise is 7:08 a.m. Sunrise will remain at 7:08 until Jan. 11, at which point it will rise one minute earlier, at 7:07 a.m. Thus begins our journey toward earlier sunrises.