About 864,938 miles Radius, diameter, and circumference The sun's average radius is 432,450 miles (696,000 kilometers), resulting in a diameter of around 864,938 miles (1.392 million km). 109 Earths might be lined up across the face of the sun. The circumference of the sun is approximately 2,713,406 miles (4,366,813 km). It takes the sun about 365 days to orbit the center of the earth.
The sun is a star that uses energy generated from the fusing of hydrogen into helium. It has the same basic chemical composition as the rest of the stars, but in greater proportion. The sun is estimated to have between 5 and 70 times the mass of our planet with a mean of 9.5. Its age is roughly 5 billion years, although it may be as young as 3 billion years or as old as 12 billion years.
Solar eclipses occur when the Moon passes between the Sun and the earth, blocking out the sun. Only certain parts of the earth directly facing the moon are able to see the eclipse; the other half is in darkness. All over the world, people notice something different about the sky during a total solar eclipse. They see the sun obscured by a dark silhouette of Earth's shadow, traveling across the surface of the moon. As the eclipse progresses, they see this dark silhouette move across the face of the moon - following the curve of Earth's surface. At some locations, such as central Africa, everyone can watch the entire eclipse simultaneously!
The diameter of the Sun is 864,400 miles (1,391,000 kilometers). This is approximately 109 times the size of the Earth. The Sun weighs approximately 333,000 times that of the Earth. It is so massive that around 1,300,000 Earths can fit inside of it.
The distance between the Sun and Earth is called an astronomical unit (au). The value of this quantity depends on how you measure it. If you go by the radius of the Earth, then it is 92,955 miles (148,540 km). If you go by the radius of the Moon, which is 3476 miles (5800 km), then it is 149 million miles (2440 million km).
In astronomy, there are several ways to measure the diameter of the Sun. One method is to use a solar telescope. With such a tool, you can see features on the Sun's surface such as sunspots or solar flares from a great distance away. By measuring the length of these features, you can estimate the diameter of the Sun accurately. For example, the Solar and Heliospheric Observatory (SOHO) is a spacecraft that has been orbiting the Sun since 1995. SOHO has a large telescope that can see details on the Sun's surface from anywhere on Earth!
Another method is to use parabolic mirrors. These mirrors focus light onto small spots where sensors are located.
The diameter of the Sun, 1,392,000 km, is 109 times that of the Earth's equatorial diameter, 12,756 km. At 149,000,000 km = 1 AU, the distance from the sun to Earth is 107 times the diameter of the sun and 388 times the Earth-Moon distance. The time it takes the Sun to orbit the center of the Galaxy is about 200 million years.
The solar cycle is the term given to the periodical change in the intensity of the Sun's activity. This change affects both the number and size of sunspots, which are areas of intense magnetic flux on the surface of the Sun. Sunspots appear dark because they block out much of the sunlight that reaches the solar surface.
The Sun goes through cycles every 11 years or so. When this happens, there are more sunspots than average. These spots cause many geomagnetic storms when they erupt into space. Also, there are fewer clouds around the planet which means more sunlight reaching the ground. This leads to more photosynthesis in the oceans and more oxygen is released into the atmosphere. Then, about 10 years later, there are less sunspots than average. This is because the last maximum sunspot cycle ended in 2003. Now there are only four years with more than 20 sunspots recorded by NASA's Solar Dynamics Observatory.
Circumference of the sun is 4.379 million kilometers. That's about 3% bigger than the radius of the solar system-about 8.5 million kilometers.
The sun is a star that uses energy to fuse hydrogen into helium. It also converts some of this energy into radiation that covers the galaxy in the form of light and heat. The sun is expected to run out of fuel and shrink down toward a white dwarf in about 5 billion years.
Stars are usually born inside clouds of gas and dust. These clouds can be very large, like our Galaxy which contains hundreds of billions of stars within its disk. Or they can be small, like the disks around individual stars.
A stellar nucleus produces energy by fusing hydrogen into helium. This process releases a lot of energy and creates many heavy elements such as carbon, oxygen, nitrogen and more. Heavier elements with greater mass come from older stars and are found in ancient rocks on Earth and elsewhere in the universe. Light elements such as hydrogen and helium are produced during nucleosynthesis and are responsible for making up most of the matter in a star.
You may Google it up; the sun's angular diameter is 0.5 deg. It's also quite simple to compute. In the diagram below, D represents the Sun's real diameter (1.392 x 106km) and d indicates the distance between the Earth and the Sun (149,598,261 km). The Sun's radius (r) will be half of D (r = D/2). Therefore, the angle θ formed by the tangent to the solar circle and the normal to the ecliptic plane is r/d. The cosine of this angle is then given by: cos(θ) =.5.
That's it! Angular diameter equals cosine of angle between planet and Sun.
Now, if you want to calculate the amount of time it takes the Sun to rotate around its axis, that's more complicated. But if you need to know how long it takes the Sun to move from one zenith to another, that's simply done by calculating the angle between these two zeniths and multiplying it by 2. For example, if you need to know when it will be sunset at a certain location on the Earth, take the angle between the local horizon and the center of the Sun, multiply it by 2 and set your watch or phone alarm accordingly.
As for sunrise, you can use the same formula but with angles in the opposite direction. That is, instead of pointing the horizon at the Sun, point it away from it.