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How big is Arcturus?

Arcturus is 36,000,000 kilometres

Introduction

Have you ever looked up at the night sky and wondered about the stars that twinkle back at you? Among all the stars you can see, there’s one that shines brighter than any other in the northern celestial hemisphere. This star is called Arcturus. Arcturus is not only fascinating because of its brightness, but also due to its size. It’s much, much bigger than our Sun!

The Size of Arcturus

Arcturus is a star that is 25 times larger than our Sun. To put that into perspective, if our Sun was the size of a basketball, Arcturus would be as large as a small car! The diameter of Arcturus, the distance from one side of the star to the other, is about 35 million kilometers. This is about 26 times the diameter of the Sun. If we were to place Arcturus in our solar system, it would stretch out past the orbit of Mars!

  • Arcturus is 25 times larger than our Sun. - If our Sun was the size of a basketball, Arcturus would be as large as a small car. - The diameter of Arcturus is about 35 million kilometers. - If placed in our solar system, Arcturus would stretch out past the orbit of Mars.

Comparing Arcturus With Other Stars

Arcturus is a red giant star, meaning it has used up most of its hydrogen fuel and has expanded. This expansion is what makes Arcturus so much larger than our Sun. However, even as big as Arcturus is, there are still many stars in the universe that are even larger. For example, Betelgeuse, another red giant star, is about 700 times bigger than our Sun, making it much larger than Arcturus.

  • Arcturus is a red giant star, which means it has expanded after using up most of its hydrogen fuel. - Betelgeuse, another red giant star, is about 700 times bigger than our Sun, and much larger than Arcturus.

Conclusion

Arcturus is an amazing star, not just because it’s the brightest star we can see in the northern hemisphere, but also due to its impressive size. It’s a giant among stars, much larger than our Sun and many other stars. Yet, it’s fascinating to know that there are still stars in the universe that are even bigger. Looking up at the night sky, it’s mind-boggling to realize just how large and vast the universe truly is, and Arcturus is a sparkling reminder of that.

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