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The Rotation of the Sun
La Rotación del Sol (Videos)
12-14 year old students
In this experience, discover what the Sun is made of and the mysteries behind its dark spots.
To prepare for a visit to ESAC, a number of materials are recommended, which can be divided into two categories:
The Sun is our closest star, at only 150 million kilometres from the Earth. If we compare the Sun with other stars in our Galaxy, the Sun is a standard dwarf star. However, it is 109 times bigger than the Earth!
Just like other stars, the Sun rotates.
The Sun is a big ball of gas and plasma with an onion-like internal structure as is shown in the image below. The centre of the star is at a temperature of around 15 000 000 K; it is here that the thermonuclear reactions (H into He) take place.
Why is the Sun so hot?
The Sun is continuously collapsing under its own gravity (due to its mass) which creates a region of very high pressures and temperatures that initiate thermonuclear reactions.
Did you know that it takes hundreds of thousands of years for the light to travel from the centre of the Sun to its surface? However, it takes only 8 minutes for the light to travel from the surface of the Sun to the Earth.
The Sun's surface can be divided into three main regions: the photosphere, the chromosphere, and the corona.
Size comparison of a sunspot to Earth ( bottom right).
By studying the movement of sunspots we can study the rotation of the Sun. Do you want to try?