Match the following. match the items in the left column to the items in the right column. 1. accretion the tendency of an object to remain in its current state; if it is at rest, to remain at rest, and if it's in motion, to remain in motion 2. cryosphere the frozen water or ice system of a planet 3. doppler effect emission of energy 4. inertia a change in the frequency of sound or light waves caused by the movement of the waves' source 5. nebula enormous cloud of gas and dust in space 6. radiation an explosion of a star that emits large amounts of matter and energy 7. supernova process of steady growth of an object by a steady accumulation of material

1. Accretion refers to the procedure in which steady growth of an object takes place due to steady accumulation of substance.  

2. Cryosphere refers to the ice system or the frozen water of a planet.  

3. Doppler Effect signifies a variation in the frequency of light or sound waves, which can assist in determining distance.  

4. Inertia refers to the capability of an object to remain in its present state, that is, if it is at rest to remain at rest, and if it is motion to remain in motion.  

5. Nebula refers to a gigantic cloud of dust and gas in space.  

6. Radiation is considered as the emission of energy.  

7. Supernova refers to an explosion of star, which discharges huge concentrations of energy and matter.