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Sun For Kids
+ NASA Home > Exploring the Universe > Our Solar System

 Why Do We Study the Sun?

We look at the sun rising every day. It’s bright, it’s big and it warms us up. Our sun happens to be the brightest object in our universe and naturally we are really curious to know more about it.

Our sun gives us light, heat and energy. It may seem that energy comes from other sources such as gasoline and electricity but the ultimate source of energy for the Earth is nothing else but the sun. Without the sun life on Earth would not exist. It would be so cold that no living thing would be able to survive and our planet would be completely frozen.

Students of Parkland Magnet School using sunspotters.
Photo above: Students of Parkland Magnet School in Rockville, MD trace sunspots using sunspotters. Photo credit: NASA/Silvia Stoyanova.
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The sun is a normal star. It is much closer to us than any other star, and by studying the sun, we can therefore learn more about other stars. The better we understand other stars, the more we know about the Milky Way. From there we know more about other galaxies and in the end we learn more about the universe.

The sun also plays the role of a big anchor, which creates gravity that keeps our planet and the other planets of the solar system in a small space. If it weren't for the sun, our planet would simply fly off loose into the universe.

ESA SOHO scientist Daniel Mueller talks to students of Parkland Magnet School in Rockville, MD
Photo above: Research SOHO scientist Daniel Mueller from the European Space Agency talks to students of Parkland Magnet School in Rockville, MD. Photo credit: NASA/Silvia Stoyanova.

Our sun is very dynamic and it changes constantly. It has the largest eruptions in the solar system. These eruptions can be so large that they can reach our planet and cause serious damage by disrupting satellites and other communication devices. Our TV may not work, our cell phones will be down, a high speed train may run loose and if an astronaut happens to be on the moon at the time when the sun erupts, he or she would be in great danger.

NASA uses satellites such as the Solar and Heliospheric Observatory (SOHO), to predict these eruptions so that we have a warning of at least 2-3 days to protect our expensive communication devices during a solar eruption. SOHO is just one of the instruments that NASA uses to help scientists understand our sun better along with other satellites and large observatories on Earth.

Here is what all of us should know about the sun.


1. The sun is a star. This makes it extremely important for life on Earth. The sun provides us with energy, which brings life on our planet. It defines the seasons, the harvests, and even the sleep patterns of all living creatures on Earth.

2. The sun is the closest star to our planet. Imagine two cars on the road during the night with their headlights on. One car is closer to you and the other one is far away. Which headlights would seem brighter and bigger? That explains why we see the sun so big and bright. It is simply the nearest star to Earth.

3. Remember! The Earth orbits around the sun.

4. The sun is way bigger than the Earth. In fact its radius is 109 times bigger than the radius of the Earth. For those of you who are curious, the sun’s Radius is 696,000km and the Earth’s radius is 6, 376km.

5. DON’T TOUCH THE SUN! IT’S HOT! The sun’s average surface temperature is 5700 C. Compare that to the Earth’s average temperature, which is 20 C.

6. The sun is 150 million km (93 million miles) away from the Earth.

7. How old is the sun? Can you imagine 4.5 billion years?

8. We know that the Earth’s structure consists of different layers. The sun also has layers but unlike the Earth, the sun is entirely gaseous; there is no solid surface.

9. The sun rotates on its axis approximately once every 26 days. The sun is made of gas, which is why its different parts rotate at different speeds. The fastest rotation is around the equator and the slowest rotation is at the sun’s polar regions (more than 30 days).

10. The sun changes. No matter when or where we look at the sun, we will always see something interesting. Scientists observe these changes by watching the sunspots. They increase and decrease on a regular cycle of about 10.8 years.

 The history of the Sun
Going back in time...
Read about the ancient history of the sun.
+ Read More
 Kids touch the Sun
Book Helps Blind Students 'Touch the Sun'
A new book, "Touch the Sun," allows blind and visually impaired students to experience images of the Sun.
+ Read More
 Celebrating SOHO's 10th Anniversary
Do you know who is watching the Sun?
NASA's satellite SOHO celebrates 10 years of Sun exploration.
+ Read More

 Track A Solar Storm

Student Observation Network: Tracking a Solar Storm
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 Solar Week
Solar Week
The ultimate Sun games and activities source for students and teachers.
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 Solar Media Viewer
NASA Solar Media Viewer
View today's image of our Sun.
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 Space Weather
Space weather can affect life on Earth...
Read about space weather and why it is important to predict solar activities.
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 Sun Earth Collection
Sun-Earth Collection
A great collection of Sun-Earth images and animations.
+ View site

 Sun For Kids Video
Sun For Kids Video
Kids talk to NASA scientists and use sun spotters to learn more about our sun.
+ View this Video
 High resolution SOHO images for media
Best of SOHO
High resolution images for media.
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 The Sun's minimum and maximum video
One Amazing Solar Cycle
View a movie about the sun's 11-year activity cycle.
+ View this Video
 Studying the Sun movie
SOHO Science in a Shell
Find out how SOHO revolutionized our ability to forecast space weather.
+ View this Video
 The best of SOHO movie
Spectacular Storms
Watch a video including the best images of SOHO.
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Editor: Silvia Stoyanova
NASA Official: Brian Dunbar
Last Updated: November 30, 2007
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