Hydrogen is by far the most abundant element in the universe. It makes up about 93 percent of all atoms in the universe and about three-quarters of the total mass of the universe. Hydrogen occurs both within stars and in the interstellar space (the space between stars).
It is an imaginary line from the Earth's north pole to its south pole, passing through the center of the Earth. Imaginary in the sense that it is not marked in any way; howeve â¦ r, Earth rotates around this axis.
In classical Cartesian algebra, the x axis is defined as a horizontal number line defining the distance from a zero point called the origin. The y axis is a vertical line de â¦ fining the vertical distance from the same origin. This system has been adapted to define axes on any number of graphing systems, from Microsoft Excel to modern machine tools.