Let's start with the heat of the human body. Human body is never constant in 24 hours, when you are healthy and sleep at night, then, the next morning, at 4.30 your body reaches its lowest temperature, and at 7:00 pm, is at its highest temperature, and the average body temperature of a healthy human for 24 hours is 37 degrees celcius. And if you have a high fever, up to or more than 42 degrees Celsius, then the body is in danger.
The hottest areas ever recorded on earth without any heat source such as fire and lava are 54 degrees celcius in Death Valley.
And 1090 degrees celsius is the temperature of the lava! then the outer temperature of the sun is 5500 degrees celsius. but the temperature of the solar core? 15 MILLION OF CELSIUS DESIGNS! or 15 million degrees Kelvin.
When an object reaches a heat, it releases radiant energy. if a very small nail is heated to the equivalent of heat from the sun's core, then the tiny needle will release radiation that can kill ALL humans within a radius of 1600 km.
All objects that are temperature above absolute zero pull out electromagnetic radiation. emit electromagnetic radiation and humans emit infrared rays that are not visible to the naked eye, but can be seen in infrared cameras. this is an example of a demonstration of a person hiding inside a large black plastic bag to cover half of his body. the human eye can not see the person, but the infrared camera can see it. You can try it yourself at home.