What is the winter solstice? Holidays, Science, Live Streaming

Winter in 2022 The solstice occurs for the northern hemisphere December 21. Although not as dramatic as in the 2020s Conjunction of Jupiter and Saturnthe longest night of the year is a significant turning point. Astronomical winter begins and the days gradually lengthen.

I wonder why this happens? spoke to WIRED Tansu DaylanFormer Transiting Exoplanet Survey Satellite (TESS) postdoctoral fellow at MIT to better understand the winter solstice and our planet’s relationship to the sun.

To visualize what happens in space during the winter solstice, start by thinking of a giant glass sphere surrounding the Earth and ignore the rotation of the planet (which complicates things). “If you look at the three-dimensional sphere that surrounds us, known as the celestial sphere, the sun and all other solar system objects move in a plane on this celestial sphere, known as the ecliptic plane,” says Daylan.

“As it does this, the sun changes its inclination,” he says. Criticism and right ascension are the two main axes of the celestial sphere. “In this frame of reference, the sun is at its southernmost point when it is the winter solstice from our perspective in the northern hemisphere.”

The winter solstice occurs in the Northern Hemisphere the north pole tilted farthest from the sun. The Arctic Circle is shrouded in darkness and experiences the longest night of the year. In the Southern Hemisphere, the summer solstice occurs at the same time as the South Pole approaches the sun and the Antarctic Circle. the midnight sun.

NASA’s online textbook Fundamentals of Spaceflight includes a section on this topic celestial sphere with illustrations for anyone who enjoys exploring the idea further.

The low position of the sun during the winter solstice will be your cause afternoon shadow to be extraordinarily long. Although important to humans, the solstice doesn’t have much meaning in relation to the larger cosmos.

“Days are determined by the Earth-Sun system, not the entire solar system. We give it a lot of meaning because the sun is very sacred to us, and its placement in the celestial sphere as a function of time throughout the year is very important,” says Daylan. “It sets the climate. It tells us when the crop will ripen throughout the year. This is especially important for historical civilizations.”