By the time the light finally reached Mars, the glint would be a million times dimmer than the faintest light visible to the human eye.
In elementary geometry the concept of a curve is not clearly defined and is sometimes defined as "length without width" or as the "boundary of a surface" . In elementary geometry the study of a curve essentially reduces to consideration of examples (a straight line, an interval, a polygon, a circle, etc.). Since it does not have general methods at its disposal