Tropic of Capricorn: the invisible line that marks the beginning of summer in Ubatuba

In many places in Brazil, summer is just a season. In Ubatuba, it's a geographic, astronomical, and symbolic landmark . The phrase " Summer starts here " isn't just a tourist slogan—it's based on a fact: Ubatuba is crossed by the Tropic of Capricorn , an invisible line that carries profound meaning for our planet and our climate.

No centro de Ubatuba, um monumento marca o ponto de passagem do Trópico de Capricórnio - uma grande Rosa dos Ventos. Fica na Praça Trópico de Capricórnio, bem em frente ao aeroporto, entre a pista de skate e a feira hippie, de frente ao mar.

What are the Tropics? The Tropics of Cancer and Capricorn are imaginary lines that run east–west across planet Earth. They delimit the Tropical Zone of Planet Earth, the hottest region on the globe.

🗓️The importance of the Tropics in determining the seasons

The seasons occur because the Earth's axis of rotation is tilted relative to the Earth's path around the Sun. Thanks to the tilt of the Earth's axis, over the course of a year, while one hemisphere receives more sunlight and has longer days, the other hemisphere receives less sunlight and has shorter days, resulting in two opposing seasons: summer and winter. The other seasons, autumn and spring, are intermediate, and their respective beginnings are marked by days and nights of equal length (the equinoxes). They also occur alternately between hemispheres; that is, when it is autumn in the Southern Hemisphere, it is spring in the Northern Hemisphere, and vice versa.

The seasons of the year in the Southern Hemisphere with their approximate starting dates (solstices and equinoxes)

What are the Solstices? At two points during the year, called solstices, the Earth's tilt results in one hemisphere experiencing maximum exposure to the sun's rays (with the longest days of the year in one hemisphere and the shortest in the other). These moments mark the beginning of summer and winter in each hemisphere.

Summer in the Southern Hemisphere:

At the summer solstice in the southern hemisphere, the Sun reaches its highest point in the sky (sunset) at the Tropic of Capricorn, while the northern hemisphere is in its winter .

Summer in the Northern Hemisphere:

Six months later, at the northern hemisphere's summer solstice, the Sun is directly overhead over the Tropic of Cancer, and the southern hemisphere experiences winter .

What are the equinoxes? They occur when the sun's rays fall perpendicularly on the equator and mark the times of year when day and night are approximately equal in length across the planet. They also mark the beginning of the intermediate seasons, spring and autumn. There are two equinoxes each year.

🧭 What is the Tropic of Capricorn?

Ubatuba is located on the Tropic of Capricorn.

The Tropic of Capricorn is an imaginary line located at latitude 23° 27′ south. It marks the southern limit of Earth's so-called "tropical zone"—the band of the planet where, on at least one day of the year, the Sun can reach its zenith , that is, be exactly 90° above the horizon , high in the sky, at noon. This phenomenon, known as "high in the sky," only occurs between the tropics, and in the case of the Tropic of Capricorn, it occurs on the summer solstice in the Southern Hemisphere, around December 21st. This day marks the official beginning of summer in the Southern Hemisphere .

☀️ Why does summer start right here?

On the December solstice, when the Sun reaches its zenith , its rays fall perpendicularly on the Tropic of Capricorn . It is the day with the longest duration of sunlight in the Southern Hemisphere, and it is when this region of the planet receives the maximum amount of direct solar energy .

As Ubatuba is located directly on the Tropic of Capricorn, the first region of the globe to receive the sun's rays at their greatest intensity at the beginning of summer, it is often said, and rightly so, that summer begins in Ubatuba — where the sun shines with maximum intensity, marking the beginning of the hottest season of the year here on our side of the globe.

Transcription of the text on the plaque next to the compass rose monument:

SUMMER SOLSTICE

The Tropic of Capricorn passes through Ubatuba right here, in this location, and has a very precise astronomical significance. A curious phenomenon occurs annually between December 21st and 22nd. This date is called the Summer Solstice, a phenomenon that occurs only once a year and makes this day the longest of the year. Ubatuba is the first city in the Southern Hemisphere to celebrate the beginning of summer. Considering this information, we can guarantee that here, in Ubatuba, summer begins! Enjoy!

Terrestrial globe located at the center of the Compass Rose.

🌴 A sensory experience.

Ubatuba's beauty goes beyond geography. The city is a true gateway to the Brazilian summer. In late spring, the days lengthen, temperatures rise, and the beaches fill with life. The Atlantic Forest, the ocean, and all of nature create a unique atmosphere.

🎯 Why does this matter to the tourist?

Knowing that Ubatuba is at the exact point that marks the beginning of summer on the planet makes the experience even more special. Here, you don't just feel summer— you experience it from the first ray of sunlight . This is the rare combination of astronomy, climate, and tourism that few destinations in the world can offer.

A visit to Tropic of Capricorn Square is well worth it, any time of year, but especially during the Summer Solstice. On your next visit to Ubatuba, be sure to register your presence here!