The average distance is about 150 million kilometers (149.6) or 93 million miles (92.9). This is defined as 1 astronomical unit, or AU, and is equal to about 8.2 light-minutes, as light from the Sun takes about 8 minutes to reach Earth.
The definition of a scourge is someone or something that causes a lot of trouble, problems or suffering. An example of a scourge is famine or the outbreak of a disease. YourDictionary definition and usage example.
The definition of a scab is  a rough or crusty piece of skin, especially one that forms over a healing wound, or a worker who refuses to strike. An example of a scab is a crust over a cut. An example of a scab is a person who takes over the job of a worker who is striking against an employer.