6 things you should know about the winter solstice, the day Austin says 'Howdy!' to winter

The first day of winter sometimes depends on who you ask. Astronomers look at the position of the Earth relative to the sun. But even under Newtonian laws of physics, that day can vary from year to year, from Dec. 20-23.

Meteorologists like to keep consistent weather records, so they start winter on Dec. 1 and end the season on the last day of February.

But as far as the Earth is concerned, we greeted the season around 4 a.m. Monday, the day of the winter solstice. Here are six things to know about this annual event:

1. It’s the year’s shortest day — or longest night. The day is still 24 hours long, but it includes the least amount of daylight. That's because the Earth spins on a tilted axis, so we get winter when the Northern Hemisphere (where we live) is tilted away from the sun and gets less daylight. The winter solstice is the moment when the North Pole is pointed the farthest away from the sun. During the summer solstice, the opposite occurs.

2. It’s NOT when Earth is farthest from the sun. Ironically, the Earth is actually closest to the sun during the winter. This season’s perihelion, or when our planet will be closest to the sun, falls on Jan. 2, 2021.

3. It’s not the year’s coldest day. Because the oceans absorb so much of the sun’s energy and release it over time, a seasonal lag exists between the amount of daylight and air temperatures. So even though we get the least amount of daylight in December, it’s typically much colder in January or February. Similarly, summer daylight is longest in June, but July and August are normally hotter.

4. It’s not the equinox. Like solstices, equinoxes happen twice a year but occur in the spring and fall. Try to think of the word “equal” with equinox because it is the moment when the sun spends the same amount of time at the Earth’s equatorial plane, giving equal lengths to day and night.

5. It happened in Austin at 4:02 a.m. Daylight in Austin on Monday will only last about 10 hours and 11 minutes. The daylight will be 3 hours and 54 minutes shorter than during next year’s summer solstice on June 20.

6. Yule never believe this, but ... The word “yule,” used to describe the Christmas season, is believed to come from the Norse word “jol” that referred to a winter solstice festival.