The motion of planets in the solar system is an example of conservation of

Mass of earth has been determined through

The galaxies are moving away from each other. It is explained by

Speed of recession of galaxy is proportional to it's distance

Great bear is a

Surface temperature of the sun is of the order of

The colour of a star is an indication of its

Which of the following is coldest planet

"The universe is expanding" means

The galaxy in which we live is