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Analysing the SunINTRODUCTION

CHARACTERISTICS OF THE SUN

STRUCTURE OF THE SUN

PHENOMENON ON THE SURFACE OF THE SUN

ANSWER

GENERATION OF SOLAR ENERGY

EVALUATION

INTRODUCTION

There are billions of galaxies in the Universe consisting of stars and planets.

All living things depend on the Sun’s energy.

The Milky Way

X

100 000 light years

30 000 light years

The Sun is a giant ball of hot glowing gases and it spins around in space.

Characteristics of the Sun

Shape

Diameter

Temperature

Gravitational force - 28 times stronger than earth

Distance from earth – 150 000 000 km

Age – Around 4 500 million years

Mass – 1.989 x 1034 kg (333 420 times the mass of earth)

Density – 1 485 kg m3

Composition - Hydrogen (90%) - Helium (8%) - Other gases (2%)

Spherical

Diameter – 1 392 000 km (109 times the diameter of earth)

1392000km

Sun

Earth

Surface temperature: 5 000oC – 6 000oC

Core temperature: 15 millionoC

Structure of the sun

The sun atmosphere is divided into 3 layers.

Corona –outermost layer

Chromosphere – middle layer

Photosphere – innermost layer

2. Chromosphere

1. Corona

Core

3. Photosphere

Prominence

CORONA

Corona

Made up of thin layer of gas Thousands of kilometers thick Visible during total eclipse of the sun Looks whitish-blue Temperature : 2 000 000 oC , the

hottest layer Emits X-ray

Corona

CORONA

Chromosphere

Layer of gas below the corona “Sphere of Colour” Reddish-pink in colour 5 000 km thick Temperature : 50 000oC Visible during eclipse of the sun

Chromosphere

CHROMOSPHERE

Photosphere

The surface of the sun 400 km thick Temperature : 6 000oC Layer of gas which can be seen from

the earth The light we get on earth comes from

this layer The sun phenomena’s – solar flares,

prominence, sunspots come from this layer

Photosphere

Phenomena on the sun’s surface

Sunspots

Prominence

Solar Flares

Sunspot

Dark patches- magnetically active

Cooler than other parts of sun

Different sizes up to several kilometers in diameter

Usually occur in pairs Last a few weeks or months Changes the earth ‘s climate

- drought

Sunspot

Sunspots

MAGNETIC FIELD AROUND A SUNSPOTS

Prominence

“Giant Flames” – clouds of burning hydrogen and helium exploding from the Sun’s surface

Appears bright red and curved can reach a height of 100 000 kilometers

Temperature – 10 000 o C Cooled down after sometimes and

pulled back by sun’s gravity

Prominence

•“Solar winds”- Escaped gases from Prominence

- Strongest during period of sunspots and causes : - climate changes, - disturb satellite, radio, tv, telegraph, telephone, computer communication

•“Aurora” – colourful phenomenon in the polar region

Effects of Prominence

Solar Winds

Aurorae

Solar flares

Huge clouds of red hydrogen and caused violent explosion

Last for a few minutes to a few hours – released a lot of energy

Temperature 5 000 000 o C Can reach earth magnetic field and

disturb satellite, radio, tv, telegraph, telephone, climate

Solar Flares

Solar Flares

The core of the sun – centre of the sun Temperature 15 000 000 o C In the core;

Hydrogen is changed to Helium.

This process produce energy that keeps the sun shining and hot

Generation of solar energy

Generation of solar energy

(Nuclear fusion)