Chapter 12: Beyond the Earth
Comprehensive Exercise (Made for exam preparation)
Class 6 Science
Question 1: Choose the correct option (Multiple Choice Questions):
1. Which of the following is the nearest star to the Earth after the Sun?
Answer: (B) Proxima Centauri.
2. What is a group of stars that appears to form a pattern or shape in the sky called?
Answer: (C) Constellation.
3. Between which two planets is the asteroid belt located?
Answer: (D) Mars and Jupiter.
4. Which day is celebrated as 'National Space Day' in India to mark the successful landing of Chandrayaan-3?
Answer: (A) 23 August.
5. Which of the following planets is commonly known as the Morning Star or the Evening Star?
Answer: (C) Venus.
Question 2: Fill in the blanks with the appropriate words:
- 1. For one full rotation about its axis, the Earth takes about 24 hours, which is called a day.
- 2. Our Solar System is a part of our home galaxy called the Milky Way (or Akash Ganga) Galaxy.
- 3. The small rocky and irregular objects revolving around the Sun, mostly found between Mars and Jupiter, are called asteroids.
- 4. Earth’s natural satellite, the Moon, takes about 27 days to complete one revolution around the Earth.
- 5. The Big Dipper is a pattern of stars in the constellation Ursa Major, and in India, it is commonly known as Saptarishi.
Question 3: State whether the following statements are True or False:
- 1. Comets are made up of dust, gases, rocks, and ice, and they develop a tail as they approach the Sun.
Answer: True. - 2. Jupiter, Saturn, Uranus, and Neptune are the inner planets that have solid surfaces with rocks on them.
Answer: False (They are the outermost giant planets, mostly made of gas). - 3. Pluto is currently classified as a dwarf planet by the International Astronomical Union (IAU).
Answer: True. - 4. Stars do not shine with their own light; they reflect the light of the Sun.
Answer: False (Stars shine with their own light). - 5. The Earth is also called the Blue Planet because a large portion of its surface is covered with water.
Answer: True.
Question 4: Match the items in Column 'A' with the correct items in Column 'B':
| Column 'A' | Column 'B' |
|---|---|
| 1. Orion | (a) The closest star to the Earth |
| 2. Mars | (b) A star in the constellation Canis Major |
| 3. Halley’s Comet | (c) Constellation often represented as a hunter |
| 4. Sun | (d) The Red Planet |
| 5. Sirius | (e) Appears periodically every 76 years |
Correct Matches:
- 1 → (c) Constellation often represented as a hunter
- 2 → (d) The Red Planet
- 3 → (e) Appears periodically every 76 years
- 4 → (a) The closest star to the Earth
- 5 → (b) A star in the constellation Canis Major
Question 5: Classification. Classify the following 5 planets into "Inner Planets" and "Outer Planets":
Planets: 1. Earth, 2. Jupiter, 3. Mars, 4. Saturn, 5. Venus.
- Inner Planets: 1. Earth, 3. Mars, 5. Venus.
- Outer Planets: 2. Jupiter, 4. Saturn.
Question 6: Answer the following questions in one sentence:
1. What is the useful unit for expressing large distances within the Solar System?
Answer: The useful unit for expressing distances within the Solar System is the 'astronomical unit' (au).
2. What are the circular bowl-like structures found on the Moon's surface called?
Answer: The circular bowl-like structures on the Moon's surface are called craters.
3. Which star appears nearly stationary and helps in locating the North direction?
Answer: The Pole Star (or Dhruva tara) appears nearly stationary and helps in locating the North direction.
4. What is a satellite?
Answer: Any object that moves around a planet, or a much larger object, is commonly called a satellite.
5. Why is Mars known as the Red Planet?
Answer: Mars is called the Red Planet because the soil on Mars is reddish in colour.
Question 7: Give scientific reasons:
1. Reason: We cannot see the other stars during the daytime.
Answer: Because during daytime, the extreme brightness of the Sun makes it impossible to view the faint light of other stars from the Earth.
2. Reason: Venus is hotter than Mercury, even though Mercury is closer to the Sun.
Answer: Because the presence of an atmosphere on Venus traps the heat, which significantly increases its temperature.
3. Reason: Craters stay on the Moon's surface for a very long time.
Answer: Because there is hardly any atmosphere, water, or life on the Moon to erode or change its surface features.
4. Reason: The Earth is also referred to as the 'Blue Planet'.
Answer: Because a large portion of the Earth’s surface is covered with water, making it appear blue when viewed from space.
5. Reason: We can easily distinguish planets from stars in the night sky.
Answer: Because unlike stars, which appear to twinkle a lot, the planets do not twinkle and appear as steady shining dots.
Question 8: Answer the following questions in short (2-3 sentences):
1. What constitutes our Solar System?
Answer: The Sun, the eight planets, their moons, and many smaller objects including asteroids and comets, together form our Solar System. The Sun is the largest object and produces almost all the energy in the Solar System.
2. State the difference between the inner and outer planets.
Answer: The inner four planets (Mercury, Venus, Earth, Mars) are smaller in size and have solid surfaces with rocks. The four outermost planets (Jupiter, Saturn, Uranus, Neptune) are much larger, mostly made of gas, and have large ring-like structures around them.
3. What is a comet? Why does it appear to have a tail?
Answer: A comet is an object made up of dust, gases, rocks, and ice that revolves around the Sun. As a comet approaches close to the Sun, the frozen material in it starts evaporating, and this evaporating material forms a long tail.
4. Briefly describe India's Chandrayaan-3 mission.
Answer: Chandrayaan-3 was India's mission to the Moon launched in July 2023. Its Vikram lander, carrying the Pragyan rover, successfully soft-landed on the Moon on 23 August 2023, making India the first country to achieve a landing near the Moon's south pole.
5. How did the constellation patterns help our ancestors in ancient days?
Answer: In ancient days, imaginary shapes and stories associated with constellations helped our ancestors in easily recognising stars in the sky. Some particular stars also helped caravans and travellers in finding directions at night.