Radiation occurs when energy is transferred by electromagnetic waves

Electromagnetic waves ARE radiation.

A wave always carries energy.

Thermal or Heat energy

Explanation:

There are three ways through which heat transfer, it include conduction, convection and radiation, so radiation is the type of heat transfer.

Electromagnetic waves are those waves which travel with the speed of light. These are generated as the result of vibration between magnetic and electric field and these fields transfer heat or thermal energy through a medium or across vacuum by the process of electromagnetic radiation.

the working equation for the angular size is the product of the physical size and 360 degrees divided by the product of two pi and distance from earth. the minimum size would be 0.559 degrees while the maximum size would be 0.49 degrees. 

compass can be used day and night, cloudy or sunny