Question

What are cosmic rays? Explain
(i) Latitude effect
(ii) Altitude effect of cosmic rays

Answer 1

Hint: When we look up at the sky, on a clear night, we can see a sky filled with stars and the Moon. Now, these far away objects are visible to us because of light emission (in case of stars) and light refraction (in case of Moon). The basis of cosmic rays is of a similar origin.

Complete step by step answer:
Cosmic rays may be defined as the high energy radiation, which are mainly originating from the outside of the Solar System. Many secondary particles will reach the earth’s surface due to these cosmic rays.
The cosmic rays can be divided into two main segments, primary and secondary cosmic rays. Here the rays coming from outer space entering the boundary of the earth's atmosphere are called the primary cosmic rays. There are 90% protons, 9% helium nuclei, etc. in the primary cosmic rays. The energy of the primary cosmic rays is around 108 MeV. The secondary cosmic rays are emitted when primary cosmic rays react with the ions of the gases which are there in the earth’s atmosphere. The secondary cosmic rays mainly consist of particles like α-particles, protons, electrons, positrons, mesons, photons, in different percentages.

Latitude effect: Latitude effect may be defined as the effect that shows the intensity of the cosmic rays with the geometrical latitude. It shows that the intensity of the cosmic rays is maximum at the poles where geometrical latitude is and is minimum at the equator where the geometrical latitude is.
The earth's magnetic field is the main reason for the decrease in cosmic ray intensity at the equator. In the poles, the charged particles are travelling parallel to the direction of the magnetic field. Thus, they can travel to earth almost unhindered so the intensity is always maximum at the poles. But when we consider the scenario of the equator, the charged particles have to travel in a perpendicular direction to the field and face the maximum hindrance. Only the particles having enough energy to cut through this barrier can reach the equator, thus we get minimum intensity at the equator.

Altitude effect: It may be defined as the effect which shows the variation of the cosmic rays intensity with the altitude (height). The cosmic rays intensity increases with the increase of the altitude and is maximum when we reach an altitude of 20Km. If we further increase the altitude then the intensity of the cosmic rays decreases. This effect is called the altitude effect.
The latitude effect is generally known as the change of the physical quantity with change in latitude whereas the altitude effect is the change of physical quantity with respect to the change in the height.

Additional information:
Cosmic rays are atom fragments that rain down on the Earth from outside of the solar system. Cosmic showers cause the speed of light which causes problems in the satellite and other space machinery. The amount of energy possessed by cosmic rays is very high. When there is an impact of the cosmic rays with the earth’s atmosphere then there is shower of secondary particles which sometimes reach the earth surface.

Note: The effect of the cosmic energy and the latitude and altitude effect can be seen in our day to day life as well. If we consider the effect of UV rays, which is a form of cosmic rays, the effect is quite widespread in the poles but not that much evident near to the equator. This can be a very practical example of Cosmic Rays and the effect of latitude and altitude on cosmic rays.