Environment & Science

Winter solstice 2015: Griffith Observatory commemorates seasonal event

A person visits the Griffith Observatory, Nov. 2, 2006 in Los Angeles.
A person visits the Griffith Observatory, Nov. 2, 2006 in Los Angeles.
Gabriel Bouys/AFP/Getty Images

Monday marks the winter solstice, the day the Earth sees the shortest amount of sunlight in the year.

To mark the occasion, Angelenos can head to the Griffith Observatory. The site is closed Mondays,  but they'll still have a couple outdoor events to the public to commemorate the occasion.

At 4:40 p.m., just before the 4:48 p.m. sunset, observatory staff will provide a play-by-play as the sun sets. The winter solstice line inscribed in the lower west terrace on the west side of the observatory will point to where the sun sets during the winter solstice. 

Before you set out, though, a few things to know:

What is the winter solstice?

A winter solstice is when the Earth's northern hemisphere starts tilting toward the sun, according to KPCC science reporter Sanden Totten. In June, the the northern hemisphere starts tilting away from the sun. 

Because the sun as it approaches either of those points appears to shift very little from day to day, solstice means “sun still,” Griffith Observatory Director Dr. Ed Krupp told KPCC.

“From the perspective of a person standing on the Earth and not realizing the Earth moving around the sun, they will see over the course of the year a gradual shift in the position of sunrise from day to day, going from northeast in June to southeast in December,” said Krupp.

More on the solstice from Krupp:

People in antiquity were very ware of this kind of thing because it was very closely linked to the seasons, and seasons are directly linked to human behavior and activity and resources.

All of this is due to the fact that the earth is moving in orbit around the sun and it’s also rotating and its axis of rotation is tipped. Because of that tilt we experience this change of seasons and that’s why we see this shift in the sunrise point over the course of the year and the same for the sunset.

When does the winter solstice take place?

In Los Angeles, it occurs Dec. 21 at 8:48 p.m. PST. Since Griffith Observatory is closed Mondays, staff working earlier in the day will be there for solstice events but not during the actual winter solstice occurrence. 

How short is the winter solstice day?

In Los Angeles, the amount of daylight in a winter solstice day is 9 hours and 53 minutes. In June — when the summer solstice marks the longest day of the year — the sun shines for 14 hours and 26 minutes.