Eclipses

Utility of the presentation

This presentation is to show how eclipses occur. As, it is not possible to show the occurrences of eclipses in the classroom.

So it is a unique opportunity to see and comprehend ( with the help of different slides presentation) eclipses.

Objectives

Concepts of Eclipses Causes of Eclipses Types of Eclipses. Importance of Eclipses. Effects Occurences of Eclipses

Concept of Eclipses The earth and the moon are both opaque objects.

They revolve around the sun(a light source). When the sunlight is obstructed by these bodies, shadows are formed. These are called ECLIPSES.

Causes of Eclipses

1.Solar Eclipse.In the course of its revolution around the earth, the moon comes between the sun and the earth. The moon blocks a part of the light from the sun. This happens on a new moon day. The shadow of the moon falls on the earth.

Solar Eclipse

SunSun

EarthEarthMoonMoon

Activity:1. Place a football on a table. It represents the earth.

2. Flash a torchlight (which represents the sun), at the football

3. Place a tennis ball (which represents the moon) between the football and the torchlight in line with them.

4. The shadow of the tennis ball( moon) falls on the football (earth). This is the SOLAR ECLIPSE

FootballFootballTennisballTennisballTorchlightTorchlight

Causes of Eclipses

2. Lunar Eclipse. During a full moon day, the earth comes between

the sun and the moon. On such a day when all the three bodies are exactly aligned, the earth casts its shadow on the moon. This causes a LUNAR ECLIPSE.

Lunar Eclipse

SunSunEarthEarth

MoonMoon

Activity

1. Place a tennis ball on a table. It represents the moon.2. Flash a torchlight (which represents the sun) at the tennis

ball.3. Place a football (which represents the earth) between the

tennis ball and torchlight in line with them. The shadow of the football (earth) falls on the

tennis ball (moon) causing a Lunar Eclipse to occur

FootballFootball

TennisballTennisball

TorchlightTorchlight

Eclipses

Solar Eclipse

Total Solar Eclipse

Partial Solar Eclipse

Lunar Eclipse

Total Lunar Eclipse

Partial Lunar Eclipse

ImportanceImportance

Scientific: During eclipses scientists and astronomers study the position of the Sun, earth, moon and star.

Mythological: Indian concept eclipses are many mythological aspect.

EffectsEffects During a solar eclipse one must never look at the

sun directly. The rays of the sun may damage the eyes.

Birds and animals mistake it for nightfall. Many astronomical problems can be studied only

during total eclipse of the sun. Today scientific solar eclipse observations are

extremely valuable.

Occurences of eclipsesRecently happened solar eclipses1.oct.24,1995---India.2.June21,2001---Africa3.June,2000---Australia

Lunar eclipses1.Jan,9-10,20012.Mar29,2006

Forecast July22,2009.