All objects emit and absorb infrared The hotter an object is, the more IR it emits in a given time. With IR time is important. Dark, matt surfaces are good absorbers, good emitters. This means that a dark, matt object will heat up faster or cool down faster than a light, shiny one. Light, shiny surfaces are poor absorbers, poor emitters, good reflectors. All objects on Earth emit IR radiation, or heat, which can be detected by electronic sensors, such as those used in night-vision goggles and infrared cameras. A simple example of such a sensor is the bolometer, which consists of a telescope with a temperature-sensitive resistor, or thermistor, at its focal point.