On this page, you will find Stars and the Solar System Class 8 Notes Science Chapter 17 Pdf free download. CBSE NCERT Class 8 Science Notes Chapter 17 Stars and the Solar System will seemingly help them to revise the important concepts in less time.
CBSE Class 8 Science Notes Chapter 17 Stars and the Solar System
Stars and the Solar System Class 8 Notes Understanding the Lesson
1. The science dealing with the study of the universe is called astronomy.
2. The scientist who study the universe are called astronomers.
3. The stars, the planets, the moon and many other objects in the sky are called celestial objects.
4. The various shapes of the bright part of the moon as seen during a month are called phases of the moon.
5. The phases of the moon occur because we can see only that part of the moon which reflects the light of the sun towards us.
6. The stars are hot glowing spheres that continuously emit their own heat and light, that is they are self luminous objects.
7. Stars appear to move from east to west.
8. The group of stars that move together and form a characteristic pattern in the sky is called constellation.
9. There are many types of constellations like Ursa Major, Ursa Minor, Orion.
10. The sun and the celestial bodies which revolve around it form the solar system. It consists of large number of bodies such as planets, comets, asteroids and meteors.
11. The sun is the nearest star from us. It continuously emits huge amounts of heat and light.
12. A planet has a definite path in which it revolves around the sun. This path is called orbit.
13. There are total eight planets in our solar system.
14. There is a large gap in between the orbits of Mars and Jupiter. This gap is occupied by a large number of small objects that revolve around the sun. These are called asteroids.
15. Comets are also members of our solar system. They revolve around the sun, in highly elliptical orbits. A comet appears generally as a bright head with a long tail.
16. Meteors are the pieces made of stones or metals or both that move very fast in space. They are also called as ‘shooting stars’.
17. Some meteors are so big in size that they do not burn up completely in the atmosphere and reach the earth’s surface. They are called meteorites.
18. A satellite is defined as a heavenly body that moves around another heavenly body along its own orbit.
19. There are two types of satellites:
- Natural satellite
- Artificial satellite
20. Aryabhatta was the first Indian satellite. Some other Indian satellites are INSAT, IRS, Kalpana, EDUSAT, etc.
21. Artificial satellites have many practical applications. They are used for forecasting weather, transmitting television and radio signals. They are used for telecommunication and remote sensing.
Class 8 Science Chapter 17 Notes Important Terms
Artificial satellite: The satellites other than natural satellites are known as artificial satellites. They are used for forecasting weather, transmitting television and radio signals.
Asteroids: Asteroids are small bodies revolving around the sun mostly between the orbits of Mars and Jupiter.
Cassiopeia: Cassiopeia is another prominent constellation in the northern sky. It is visible during winter in the early part on the night.
Celestial objects: Objects such as stars, the planets, the moon and many other objects in the sky are called celestial objects.
Comets: Comets are small, icy objects that orbits the sun and has a long tail of gas. They revolve around the sun in highly elliptical orbits.
Constellations: The group of stars that move together and form a characteristic pattern in the sky are called constellations.
Light year: The distance travelled by light in one year is known as light year.
Meteorites: Some meteors are so large that a part of them reaches the surface of the Earth before they evaporate completely. These are called meteorites.
Meteors: A meteor is a small heavenly object moving around the sun. When a meteor occasionally enters the Earth’s atmosphere it gets heated up because of friction and glows but evaporates in a very short period of time.
Natural satellites: A natural celestial body revolving around another celestial body is called natural satellites.
Orbit: A planet revolves around the sun in a definite path. This path is known as orbit of the planet.
Orion: Orion is a constellation which contain 7 or 8 stars. It looks like a hunter.
Phases of Moon: The various shapes of the bright part of the moon as it is seen during a month are called phases of moon.
Planets: The celestial bodies that revolve around the sun in a well defined orbit are known as planets.
Pole star: The only star which always appears to remain at the same position in the sky is known as pole star.
Remote sensing: It is scanning of the earth by artificial satellite for collecting information from distance.
Solar system: The sun and the celestial bodies which revolve in the space form the solar system.
Stars: Stars are the celestial bodies which emit light of their own. The sun is also a star.
Ursa Major: Ursa major is a constellation which constitutes seven stars and is also known as ‘SaptarishV.