Universe And Space Science Book Back Questions 8th Science Lesson 8

8th Science Lesson 8

8] Universe And Space Science

Book Back Questions with Answer and Do You Know Box Content

Do You Know?

Rockets were invented in China, more than 800 years ago. The first rockets were a cardboard tube packed with gunpowder. They were called fire arrows. In 1232 AD, the Chinese used these ‘fire arrows’ to defeat the invading Mongol army. The knowledge of making rockets soon spread to the Middle East and Europe, where they were used as weapons.

Polar Satellite Launch Vehicle (PSLV) and Geosynchronous Satellite Launch Vehicle (GSLV) rockets are India’s popular rockets.

Rakesh Sharma, an Indian pilot from Punjab was selected as a ‘Cosmonaut’ in a joint space program between India and Soviet Russia and become the first Indian to enter into the space on 2^nd April, 1984.

Kalam Sat is the world’s smallest satellite weighing only 64 gram. It was built by a team of high school students, led by Rifath Sharook, an 18 year old school student from ‘Pallapatti’ near Karur, Tamil Nadu. It was launched into the space on 22^nd June 2017 by NASA.

Know your scientist: Dr. Mylsamy Annadurai was born on 2^nd July 1958, at Kodhavadi, a small village near Pollachi in Coimbatore district. He pursued his B.E. degree course at Government College of Technology, Coimbatore. In 1982, he pursued his higher education and acquired an M.E. degree at PSG College of Technology, Coimbatore. In the same year he joined the ISRO as a scientist. And later, he got his doctorate degree from Anna University of Technology, Coimbatore. Annadurai is a leading technologist in the field of satellite system. He has served as the Project Director of Chandrayaan-1. He has also made significant contributions to the cost effective design of Chandrayaan.

Mars is the fourth planet from the Sun. it is the second smallest planet in the solar system. Mars is called as the Red Planet because in its reddish colour. Iron Oxide present in its surface and also in its dusty atmosphere gives the reddish colour to that planet. Mars rotates about its own axis once in 24 hours 37 minutes. Mars revolves around the Sun once in 687 days. The rotational period and seasonal cycles of Mars are similar to that of the Earth. Astronomers are more curious in the exploration of Mars. So, they have sent many unwanted spacecrafts to study the planet’s surface, climate, and geology.

India became the first Asian country to reach Mars and the first nation in the world to achieve this in the first attempt. Soviet Space Program, NASA, and European Space Agency are the three other agencies that reached Mars before ISRO.

Know your scientist: Dr. Kailasa Vadivoo Sivan is the chairperson of the Indian Space Research Organisation (ISRO). He was born in Sarakkalvilai, in Kanyakumari district of Tamil Nadu. Sivan graduated with a bachelor’s degree in Aeronautical Engineering from Madras Institute of Technology in 1980. Then he got his master’s degree in Aerospace Engineering from Indian Institute of Science, Bangalore in 1982, and started working in ISRO. He completed his doctoral degree in Aerospace Engineering from Indian Institute of Technology, Bombay in 2006. He was appointed as Chairman of ISRO from 10^th January 2018. Sivan is popularly known as the ‘Rocket Man’ for his significant contribution to the development of cryogenic engines for India’s space programs. The ability of ‘ISRO’ to send 104 satellites in a single mission is a great example of his expertise.

The Moon is the only natural satellite of the Earth. It is at a mean distance of about 3,84,400 km from the Earth. Its diameter is 3,474 km. It has no atmosphere of its own. It doesn’t have its own light, but it reflects the sunlight. The time period of rotation of the Moon about its own axis is equal to the time period of revolution around the Earth. That’s why we are always seeing its one side alone.

The members present in the crew during the Man Landing Mission were Neil Armstrong, Buzz Aldrin and Michael Collins.

Kalpana Chawla travelled over 10.4 million miles in 252 orbits of the earth, logging more than 372 hours in space.

Choose the best answers:

1. Which of the following is a celestial body?

(a) Sun

(b) Moon

(c) Stars

(d) All the above

2. Mangalyaan was sent to _______________

(a) Moon

(b) Mars

(c) Venus

(d) Mercury

3. Chandrayaan – 1 was launched on

(a) 22^nd October 2008

(b) 8^th November 2008

(c) 22^nd July 2019

(d) 22^nd October 2019

4. ________________ is called as Red planet.

(a) Mercury

(b) Venus

(c) Earth

(d) Mars

5. Which of the following is the working principle of Rockets?

(a) Newton’s first law

(b) Newton’s second law

(c) Newton’s third law

(d) All the above

6. Cryogenic fuels are stored at

(a) Room temperature

(b) Low temperature

(c) Very low temperature

(d) Very high temperature

7. _____________ was the first manned mission of NASA to go to the moon.

(a) Apollo – 5

(b) Apollo – 8

(c) Apollo – 10

(d) Apollo – 11

Fill in the blanks:

1. The study about stars and planets are known as ____________.

2. Our sun belongs to ____________ Galaxy.

3. Mars revolves around the Sun once in ____________ days.

4. ____________ is India’s first interplanetary mission.

5. __________________ was the first man to walk on the surface of the Moon.

State true or false. If false, correct the statement:

1. The Sun and the celestial bodies from solar system.

2. Chandrayaan-1 was launched from Sriharikota.

3. Mars is the smallest planet in the solar system.

4. PSLV and GSLV are India’s popular satellites.

5. The propellant of rocket is only in the form of solids.

Match the following:

1. Chandrayaan – Fuel

2. Mangalyaan – Moon

3. Cryogenic – First manned mission to the moon

4. Apollo – 8 – First man landing mission to the moon

5. Apollo – 11 – Mars

Answers:

Choose the best answers:

1. All the above 2. Mars 3. 22nd October 2008 4. Mars 5. Newton’s third law 6. very low temperature 7. Apollo-8

Fill in the blanks:

1. Astronomy 2. Milky way 3. 687 4. Mars orbiter mission 5. Neil Armstrong

State true or false. If false, correct the statement:

1.True

2.True

3.False

Correct answer: Mercury is the smallest planet in the Solar system

4.True

5.False

Correct answer: The propellant of a rocket is may be in the form of solids or liquids

Match the following:

1.Chandrayaan- Moon

2.Mangalyaan- Mars

3.Cryogenic – Fuel

4.Apollo – 8 – First manned mission to the moon

5.Apollo – 11- First man landing mission to the moon