Chapter 12: Beyond Earth Worksheet
Chapter 12: Beyond Earth
Worksheet
SECTION A:
I. Multiple Choice Questions
Which is the brightest star in the night sky?
(i) Pole Star
(ii) Sirius
(iii) Alpha Centauri
(iv) Sun
The star that appears almost stationary in the northern night sky is called:
(i) Sirius
(ii) Betelgeuse
(iii) Pole Star (Dhruva Tara)
(iv) Rigel
A group of stars forming a recognizable shape or pattern in the sky is called a:
(i) Galaxy
(ii) Solar System
(iii) Constellation
(iv) Asteroid Belt
The constellation Orion is also known by what traditional name in India?
(i) Saptarishi
(ii) Vyadha
(iii) Dhruva
(iv) Akash Ganga
Which celestial body is known as the "Evening Star" or "Morning Star"?
(i) Mars
(ii) Jupiter
(iii) Venus
(iv) Mercury
The main source of energy for the Earth and the entire Solar System is:
(i) The Moon
(ii) The Sun
(iii) Pole Star
(iv) Jupiter
Which of the following is not a planet in our Solar System?
(i) Neptune
(ii) Pluto
(iii) Uranus
(iv) Saturn
Small rocky bodies that revolve around the Sun, mostly located between the orbits of Mars and Jupiter, are called:
(i) Comets
(ii) Satellites
(iii) Asteroids
(iv) Meteors
What is Earth’s only natural satellite?
(i) Sun
(ii) Venus
(iii) Moon
(iv) Phobos
A celestial object made of dust, ice, and rock that develops a glowing tail when approaching the Sun is a:
(i) Comet
(ii) Asteroid
(iii) Planet
(iv) Star
Which planet is famously known as the "Red Planet"?
(i) Venus
(ii) Mars
(iii) Jupiter
(iv) Saturn
The planet that has prominent, beautiful rings around it is:
(i) Jupiter
(ii) Saturn
(iii) Uranus
(iv) Mars
The fainter band of light spanning across a clear, dark night sky represents our home galaxy, known as:
(i) Andromeda
(ii) Milky Way (Akash Ganga)
(iii) Orion Galaxy
(iv) Solar System
Why do planets not twinkle like stars?
(i) They produce their own bright light
(ii) They are much closer to Earth and appear as larger disks of light
(iii) They do not reflect sunlight
(iv) They are covered in ice
What causes the faint footprints of astronauts to remain on the surface of the Moon for millions of years?
(i) Strong wind
(ii) Absence of liquid water and atmosphere to erode them
(iii) Heavy rainfall
(iv) High gravity
II. Fill in the Blanks
Stars appear to move in the sky from ___________ to ___________.
The distance between Earth and the Sun is approximately ___________ million kilometers.
The constellation Saptarishi is also known as the ___________.
Venus is the ___________ planet in our Solar System due to its thick atmosphere trapping heat.
The ___________ Belt is located between the orbits of Mars and Jupiter.
The Pole Star always indicates the ___________ direction.
Natural objects that revolve around a planet are called ___________.
The sun and all the celestial bodies that revolve around it form the ___________ system.
Stars produce their own ___________ and ___________.
The bright celestial object that produces a long glowing tail pointing away from the Sun is called a ___________.
III. True or False
The Sun is a star.
Pluto is currently classified as one of the eight major planets of the Solar System.
The Pole Star appears to change its position continuously throughout the night.
Comets shine by generating their own internal light through nuclear fusion.
The Moon does not produce its own light; it reflects the light of the Sun.
IV. Match the Following
| Column A | Column B |
| (i) Satellite of Earth | (a) Vyadha |
| (ii) Red Planet | (b) Venus |
| (iii) Brightest star in the night sky | (c) Mars |
| (iv) Evening Star | (d) Moon |
| (v) Orion in Indian astronomy | (e) Sirius |
V. Very Short Answer Questions
Name the planet nearest to the Sun.
Name the planet farthest from the Sun among the eight planets.
What is a constellation?
How many main stars form the pattern of the Big Dipper (Saptarishi)?
Which instrument is commonly used by astronomers to observe distant celestial objects?
Why does the Sun appear so much larger and brighter than other stars?
Name the two planets between which the Asteroid Belt is located.
What is the Indian name for the Milky Way galaxy?
Do planets twinkle in the night sky?
Name the star closest to our Solar System.
VI. Short Answer Questions
Why are stars not visible during daytime?
Differentiate between a Planet and a Star (give 3 differences).
Explain how you can locate the Pole Star with the help of the Big Dipper (Saptarishi).
What is a comet? Why does a comet develop a glowing tail when it nears the Sun?
Why is Earth the only known planet in our Solar System to support life?
VII. Long Answer Questions (7 Questions)
Describe the Solar System. Name all eight planets in order of their increasing distance from the Sun and briefly describe any two of them.
What are constellations? Describe any two well-known constellations mentioned in your textbook, including their traditional Indian names and shapes.
Explain the apparent motion of stars in the night sky. Why does the Pole Star appear stationary while other stars appear to move from east to west?
Write a detailed note on natural satellites with special reference to Earth's Moon. Describe its surface conditions and why human footprints stay preserved on it.
What is the Milky Way Galaxy? Explain our Solar System's position within it and how it appears in a clear, dark night sky.
Imagine you are planning a night sky watching session. What conditions, equipment, and precautions are recommended for a successful observation?
Contrast Asteroids and Comets. Explain their composition, location/orbit, and physical appearance when viewed from Earth.
ANSWER KEY
I. MCQs
(ii) Sirius
(iii) Pole Star (Dhruva Tara)
(iii) Constellation
(ii) Vyadha
(iii) Venus
(ii) The Sun
(ii) Pluto
(iii) Asteroids
(iii) Moon
(i) Comet
(ii) Mars
(ii) Saturn
(ii) Milky Way (Akash Ganga)
(ii) They are much closer to Earth and appear as larger disks of light
(ii) Absence of liquid water and atmosphere to erode them
II. Fill in the Blanks
East, West
150
Big Dipper
hottest
Asteroid
North
Natural satellites (or Moons)
Solar
Heat, Light
Comet
III. True or False
True
False (Pluto is classified as a dwarf planet)
False (The Pole Star remains stationary in the northern sky)
False (Comets reflect sunlight; their gases glow when heated by the Sun)
True
IV. Match the Following
(i) Satellite of Earth - (d) Moon
(ii) Red Planet - (c) Mars
(iii) Brightest star in the night sky - (e) Sirius
(iv) Evening Star - (b) Venus
(v) Orion in Indian astronomy - (a) Vyadha
V. Very Short Answers
Mercury
Neptune
A constellation is a recognizable group or pattern formed by stars in the night sky.
Seven stars.
Telescope.
Because the Sun is much closer to the Earth compared to all other stars.
Mars and Jupiter.
Akash Ganga.
No, planets do not twinkle because they appear as extended disks of light rather than point sources.
Proxima Centauri (or the Sun, as the absolute closest star to Earth).
VI. Short Answers
Why stars are not visible during daytime:
During the daytime, the extreme brightness of sunlight scatters in Earth's atmosphere, hiding the faint light coming from distant stars.
Difference between a Planet and a Star:
Star: Emits its own light and heat; appears as a twinkling point of light; remains relatively fixed in constellation patterns.
Planet: Does not emit its own light (reflects sunlight); shines steadily without twinkling; changes position relative to stars over time.
Locating the Pole Star using the Big Dipper:
Locate the two stars at the outer edge of the bowl of the Big Dipper (known as pointer stars). Draw an imaginary straight line extending through these two stars northward. This line leads directly to a moderately bright star—the Pole Star.
Comets and their tail:
A comet is a celestial body made of ice, dust, and rock. When it approaches the Sun along its elongated orbit, solar heat causes its ice to vaporize, releasing gas and dust that form a long, glowing tail extending away from the Sun.
Why Earth supports life:
Earth has an optimal distance from the Sun, liquid water, an atmospheric envelope containing oxygen, and a moderate temperature range suitable for living organisms.
VII. Long Answers
The Solar System and Planets:
The Solar System consists of the Sun, eight planets, their natural satellites (moons), dwarf planets, asteroids, comets, and meteoroids, all held together by gravitational attraction.
Order from the Sun: 1. Mercury, 2. Venus, 3. Earth, 4. Mars, 5. Jupiter, 6. Saturn, 7. Uranus, 8. Neptune.
Mars: Known as the Red Planet due to iron-rich reddish dust on its surface; cold and thin-atmopshered.
Saturn: Famous for its majestic system of broad, shining rings made of ice particles and rock chunks.
Constellations:
Constellations are groups of stars that form imagined figures of animals, mythical figures, or objects in the night sky.
Big Dipper / Ursa Major (Saptarishi): A group of seven prominent stars shaped like a large ladle or dipper. It helps navigate and locate the Pole Star.
Orion (Vyadha/Mriga): A brilliant constellation visible during winter, shaped like a hunter holding a bow/shield. It features three aligned stars forming "Orion's Belt".
Apparent Motion of Stars & The Pole Star:
Earth rotates on its axis from West to East. Consequently, all celestial bodies (Sun, Moon, stars) appear to move in the opposite direction—from East to West across the sky.
However, the Pole Star lies almost directly above Earth's northern axis of rotation. As Earth spins, the axis point remains stationary relative to the observer, making the Pole Star appear unmoving while other stars revolve around it.
Natural Satellites & The Moon:
Natural satellites are non-stellar objects that orbit planets. The Moon is Earth's only natural satellite, orbiting Earth approximately every 27.3 days.
Surface Conditions: The Moon has a dusty, barren surface full of craters and mountains. It lacks liquid water, atmosphere, and weather.
Footprints Preservation: Because there is no air, wind, or rain to blow or wash dust away, footprints left behind by astronauts (e.g., Apollo missions) remain undisturbed indefinitely.
The Milky Way Galaxy:
A galaxy is a massive collection of billions of stars, dust, and gas clouds bound by gravity. Our Solar System belongs to the Milky Way Galaxy (in India called Akash Ganga).
When viewed from a dark rural area on a clear, moonless night, it appears as a faint, hazy white band of light stretching across the sky, formed by the collective light of billions of distant stars.
Night Sky Observation Guide:
Location: Choose a clear, dark open space away from city lights, high buildings, and air pollution.
Conditions: Prefer cloudless, dark moonless nights for optimal visibility of faint stars and galaxies.
Equipment: Use star charts, sky map apps, binoculars, or small telescopes.
Preparation: Allow eyes 15–20 minutes to adjust to darkness; carry warm clothing and observe under adult supervision.
Comparison of Asteroids and Comets:
Asteroids: Composed mainly of rock and metal; located predominantly in the Asteroid Belt between Mars and Jupiter; appear as faint point-like rocky bodies without tails.
Comets: Composed of ice, frozen gases, dust, and rock ("dirty snowballs"); move in highly elongated eccentric orbits far beyond outer planets; form a glowing coma and long gas/dust tail when close to the Sun.
Comments
Post a Comment