Test: Our Universe- 2 - Class 3 MCQ

• Uranus orbits our Sun, a star, and is the seventh planet from the Sun at a distance of about 1.8 billion miles (2.9 billion kilometers).

• Jupiter, being the biggest planet, gets its name from the king of the ancient Roman gods.

The revolution of the Earth around the Sun on a tilted axis.

An astronomer is a scientist who studies celestial bodies such as moons, planets, stars, nebulae, and galaxies.

An astronomer needs a telescope to see distant objects like planets and galaxies which are far off in the universe.

• Sun is the center of the solar system.
• Although, earlier it was believed that Earth forms the center of the solar system.
• However, after studies conducted by scientists it was proved that sun is at the center of the universe and all celestial bodies revolve around the sun.

• All these scientists came together to form a new model.
• They had to face immense criticism for proposing this theory that sun is at the center of the universe, because earlier it was believed that earth is the center of the solar system.
• However, with their experiments these scientists proved that sun is at the center of the solar system.

The main reason why is the earth called the blue planet is that the surface of the earth is mostly covered with different water bodies. Almost 70% or three-fourths of the planet is covered by water bodies making it appear blue from outer space. 

There is no atmosphere or air on moon. Therefore, without oxygen mask it would be impossible to breathe on moon.

• Moon doesn't change its shape.
• The part of the moon on which the shadow of the Earth falls, remains away from the sunlight and thus it doesn't appear at all.
• As the Earth, the Sun and the Moon constantly revolve, the part of the Moon away from the sunlight increases or decreases.