Download - The Sun (Helios)
SUN
Helios in Greeks
Sol in Romans
Our sun is a star located at the center of our Solar System. It is a huge, spinning ball of hot gas and nuclear reactions that lights up the Earth and provides us with heat.
THE SIZE OF THE SUN
The Sun's diameter is 864,938 miles (1,391,980 km). This is almost 10 times larger than the planet Jupiter and about 109 times as big as the Earth.
THE SIZE OF THE SUN
As compared to other stars, however, the Sun is about average; red giants like Betelgeuse are about 700 times bigger than our Sun (and roughly 50 times as massive).
Betelgeuse is also about 14,000 times brighter than the Sun. Red supergiants dwarf the Sun.
THE MASS OF THE SUN
The volume of the Sun is 1,299,400 times bigger than the volume of the Earth; about 1,300,000 Earths could fit inside the Sun
The mass of the sun is decreasing over time, as fusion reactions convert hydrogen into helium, releasing huge amounts of energy in the process.
The Sun's mass is roughly 1.99 x 1030 kg. This is about 333,000 times the mass of the Earth. The Sun contains 99.8% of all of the mass of the Solar System.
DISTANCE
PERIHELION January 2 each year
(91.4 million miles = 147.1 million km).
APHELIONJuly 2 each year (94.8
million miles = 152.6 million km).
STRUCTURE OF THE SUN
The Core: The SUN’S CORE temperature is roughly 15 million °C.
At this temperature, NUCLEAR FUSION OCCURS, turning four hydrogen nuclei into a single helium nucleus plus a LOT of energy.
STRUCTURE OF THE SUN
The Radiative Zone (or radiation zone): The next layer out from the core which emits radiation. This radiation diffuses outwards. The temperature ranges from one million °C to 15 million °C.
STRUCTURE OF THE SUN
The Convective Zone: In this next layer, photons continue to make their way outwards via convection (towards lower temperature and pressure). The temperature ranges from one million °C to 6,000 °C.
STRUCTURE OF THE SUN
The Photosphere: This is the lower atmosphere of the Sun and the part that we see (since it emits light at visible wavelengths).
This layer is about 300 miles (500km) thick. The temperature is about 5,500 °C.
STRUCTURE OF THE SUN
The Chromosphere: This reddish layer is an area of rising temperatures. The temperature ranges from 6,000 °C to 50,000 °C. This layer is a few thousand miles (or kilometers) thick.
STRUCTURE OF THE SUN
The Corona: This is the outer layer of the Sun's atmosphere. The corona extends for millions of miles and the temperatures are tremendous, reaching one million °C.
SUNSPOTS
Sunspots are relatively cool, dark patches on the sun's surface. They come in many shapes and sizes; they often appear in groups. These spots are much bigger than the Earth; they can be over 10 times the diameter of the Earths.
GRANULES
GRANULES:Granules are regions of the sun where hot solar material comes to the solar surface.
CORONAL FEATURES
HELMET STREAMERS (bottom left)POLAR PLUMES (B)
CORONAL HOLES (C)
CORONAL LOOPS (bottom right)
SUN
Nothing is more important to us on Earth than the Sun. Without the Sun's heat and light, the Earth would be a lifeless ball of ice-coated rock. The Sun warms our seas, stirs our atmosphere, generates our weather patterns, and gives energy to the growing green plants that provide the food and oxygen for life on Earth.
END
References:http://
www.enchantedlearning.com/subjects/astronomy/sun/sun.shtml
“Exploration- An Introduction to Astronomy” Fourth Edition by Thomas T. Arny 2006