MAK LABS — Std 5 EVS 1 Chapter 1 Our Earth and Our Solar System

1What's the solution? One of the asteroids has fallen out of its place in the asteroid belt and is hurtling toward the sun. Our earth is in its way and there is all likelihood of a collision. What can be done to prevent this collision?

If an asteroid is found to be on a path that could collide with Earth, scientists would first observe and calculate its orbit carefully.

Step 1: Track the asteroid and calculate whether its path will cross the path of Earth.

Step 2: If a collision is likely, send a spacecraft to the asteroid.

Step 3: The spacecraft can give the asteroid a small push or otherwise alter its motion.

Step 4: A small change made sufficiently early can make the asteroid miss Earth.

Thus, careful observation and changing the asteroid's path can help prevent a collision and protect Earth.

2Use your brain power!

(1) What will happen to our solar system if the sun were to suddenly disappear?

If the Sun suddenly disappeared, the solar system would become dark and extremely cold. The planets would no longer remain in their present orbits around the Sun. Earth would lose the sunlight and heat necessary for life, so life as we know it could not survive.

(2) Suppose you want to give your address to a friend you have on the planet Mars. How will you write your address if you want them to understand exactly where you live?

Sample address:

Name: Your Name
Planet: Earth
Continent: Asia
Country: India
State: Maharashtra
City/Town: Your City
Street Address: Your Street and House Number
Postal Code: Your Postal Code

This gives the address step by step, beginning with the planet and ending with the exact house location.

Note: This is an open-ended question. Write your own real address in the same order.

3In the picture below, correct the sequence of the planets from the sun.

The correct sequence of the planets from the Sun is:

Correct order of the planets outward from the Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.

Answer: Sun → Mercury → Venus → Earth → Mars → Jupiter → Saturn → Uranus → Neptune

4Who am I?

(a) You can see me from the earth but the lighted part of me that you see changes every day.

Answer: The Moon

(b) I have my own light. It is only from me that the planets get light and heat.

Answer: The Sun

(c) I turn around myself, around a planet and also around a star.

Answer: A satellite

(d) I turn around myself and revolve around the sun.

Answer: A planet

(e) No other planet has a living world like mine.

Answer: The Earth

(f) I am the nearest star to the earth.

Answer: The Sun

5Answer the following questions.

(a) For what purpose are rockets used in space travel?

Rockets are used to carry spacecraft, satellites and other equipment from Earth into space. They provide the powerful thrust needed to overcome Earth's gravity and place these objects into space or into orbit.

Launch spacecraft and artificial satellites.
Help scientists explore the Moon, planets and other parts of space.
Carry scientific instruments and equipment for research.
Support space missions and communication systems.

(b) What information do man-made satellites provide?

Man-made satellites collect and send useful information about Earth and space. They provide:

Weather information and data used for weather forecasting.
Location and navigation information through satellite-based systems.
Communication signals for television, telephones and internet services.
Images and observations of Earth useful for mapping and studying land, water and the environment.

1. Our Earth and Our Solar System

Exercise