For this first special episode of Futura in the Stars, embark on a journey around the Sun, discovering the solstices and equinoxes. Do you want not to miss any of the news? To learn new things every day? Or simply to immerse yourself in a sound journey? Discover Futura Podcasts! Futura in the Stars is the unmissable event for astronomy and space enthusiasts. For this first special episode, we will talk about equinoxes and solstices, on the occasion of the spring equinox which will occur on March 20. Embark on this journey around the Sun, in the company of Franck Menant. To go further: Podcast transcript Hello everyone, and welcome to this special first episode of Futura in the Stars, the new Futura podcast dedicated to astronomy. I am Franck, and in addition to offering you a selection of upcoming astronomical observations every 1st of the month, I will also meet you every 15th of the month for a special episode dedicated to a particular theme. For this month of March, we are going to talk about the equinoxes and the solstices. So remember to subscribe to your favorite audio apps so you don’t miss an episode, and if you like our work, consider leaving us a comment with the hashtag FuturaPod and five stars on the streaming platforms to help us grow. Our planet is made up of two hemispheres: the northern hemisphere, and the southern hemisphere, which are separated in the center of the globe by the equator. As you already know, the Earth turns on itself in about 24 hours, and turns around the Sun in a year. However, the equator is not perfectly aligned facing the Sun. Instead of being perpendicular to it, the Earth’s axis of rotation is tilted 23 ° relative to the plane of its orbit. Thus, in summer, we can say that the northern hemisphere leans towards the Sun while the southern hemisphere seems to move away from it. And the reverse happens in winter, when the Earth is on the other side of its orbit. This is what gives rhythm to the seasons, and the length of day and night in the two hemispheres. This is also why the seasons are reversed from one hemisphere to another. Now let’s take a one-year trip around the Sun. We are December 21st. The Sun is vertically above the southern hemisphere, it is summer. The days are long, and the nights short, and it is hot there. For the northern hemisphere, it is the opposite: the days are short, and the nights are long, and it is cold there. It’s winter. For three months, the Earth will make a quarter turn around our star. As the days go by, and due to the inclination of its axis of rotation, the equator will gradually descend towards the Sun. It therefore benefits from a longer illumination time, and we see the length of the day will decrease in the southern hemisphere, while it increases in the northern hemisphere. On March 20, the Sun is vertically above the equator. On this day, the length of day and night is equal everywhere on the globe. It is the March equinox. For the northern hemisphere, it marks the beginning of spring. And since things are turned around in the Southern Hemisphere, it marks the start of fall for this one. For three more months, the Earth will make a new quarter turn, while this time, the northern hemisphere tilts towards the Sun. During this time, the length of the day continues to increase for this one, and to decrease in the southern hemisphere. On June 21, our star is vertically above the northern hemisphere, and we speak of the June solstice. The latter marks the beginning of summer for the northern hemisphere with its longest day, and the beginning of winter for the southern hemisphere with its shortest day. From the solstice, the trend is reversed. The equator rises towards the Sun, and the day decreases again in the northern hemisphere as it lengthens to the south. Three months and a new quarter turn later, on September 22, our star is found vertically above the equator. The length of day and night is identical at every point of the globe and this time we are talking about the September equinox. It marks the beginning of autumn for the northern hemisphere, and, you guessed it, spring for the southern hemisphere. If we continue, the latter continues to rise towards the day star, the days lengthen there and the long winter nights resume their place in the northern hemisphere. Three more months, and a last quarter turn, and here we are back to the starting point for the December solstice. Occurring on the 21st of the month, it marks the onset of summer and the longest day for the southern hemisphere, and the onset of winter as well as the shortest day for the northern hemisphere. Then we start a new cycle. To recap, we therefore have two equinoxes and two solstices per year. The spring and fall equinoxes, and the summer and winter solstices. They are also called the March and September equinoxes, and the June and December solstices. It is also preferable to use this term when speaking on a global scale, because, if you have followed correctly, what we will call the spring equinox in the northern hemisphere on March 20 will correspond in made on the autumn equinox in the southern hemisphere. Finally, a little tip: if you ever fear mixing your brushes between solstice and equinox, know that the term equinox comes from Latin and means “equal night”: Equi – nox. Implied: the moment when the duration of the night is equal to that of the day. Thanks for listening to this Futura in the Stars podcast. If you like our work, feel free to leave us a comment with the hashtag #FuturaPod to help more people find out about us. You can find us on Apple Podcast, Spotify, Deezer, Castbox and many others to never miss a single episode. As for me, I will meet you on April 1, and it is not a fish, for a selection of events to observe in the sky during the next month. Music: Intro and outro by Patricia Chaylade Diving in the oceans of Kepler and Diamond rain on Saturn by MusicLFiles This will also interest you Interested in what you just read?