A sensor device positionable in an external environment subject to thermal radiation, for example solar radiation, so that it is traversed by the air thereof, the sensor device being usable with at least one data processing logic unit programmed to calculate the correct air temperature of the external environment starting from the detection of at least one first and at least one second temperature value ( Ts1, Ts2) by the sensor device and subsequent correction of the radiative error of such detection, the sensor device including: - a support structure comprising at least one seat designated to be traversed by the air of the external environment, said at least one seat having an air inlet and an air outlet; - sensor means arranged inside said seat for detecting said at least one first value and at least one second value of the detected temperature of the air of the external environment that traverses it; wherein said seat is configured so that upon detecting said at least one first value and at least one second value of the detected temperature of the air of the external environment that passes through it respectively at a first speed and at a second speed; wherein said seat has a predetermined configuration so that said sensor means are impacted by a first and a second radiant power ( PRad1, PRad2) which ratio, called third ratio ( PRad2/PRad1), is predetermined; characterized in that said seat has a geometry configured to minimise the turbulence of the air of the external environment that traverses it so that the motion of the latter is of the laminar type, in such a manner that the first ratio (V1/V2) between said first speed and said second speed is predetermined; so that the data processing logic unit is programmed to calculate the correct air temperature of the external environment subject to thermal radiation that traverses said seat starting from: - said at least one first detected temperature value and at least one second detected temperature value; and from - said third predetermined ratio (PRad2/PRad1) between said first radiant power (PRad1) and said second radiant power ( PRad2); and from - said first predetermined ratio( V1/V2) between said first speed and said second speed. - a support structure comprising at least one seat designated to be traversed by the air of the external environment, said at least one seat having an air inlet and an air outlet; - sensor means arranged inside said seat for detecting said at least one first value and at least one second value of the detected temperature of the air of the external environment that traverses it; wherein said seat is configured so that upon detecting said at least one first value and at least one second value of the detected temperature of the air of the external environment that passes through it respectively at a first speed and at a second speed; wherein said seat has a predetermined configuration so that said sensor means are impacted by a first and a second radiant power ( PRad1, PRad2) which ratio, called third ratio ( PRad2/PRad1), is predetermined; characterized in that said seat has a geometry configured to minimise the turbulence of the air of the external environment that traverses it so that the motion of the latter is of the laminar type, in such a manner that the first ratio (V1/V2) between said first speed and said second speed is predetermined; so that the data processing logic unit is programmed to calculate the correct air temperature of the external environment subject to thermal radiation that traverses said seat starting from: - said at least one first detected temperature value and at least one second detected temperature value; and from - said third predetermined ratio (PRad2/PRad1) between said first radiant power (PRad1) and said second radiant power ( PRad2); and from - said first predetermined ratio( V1/V2) between said first speed and said second speed. - said at least one first detected temperature value and at least one second detected temperature value; and from - said third predetermined ratio (PRad2/PRad1) between said first radiant power (PRad1) and said second radiant power ( PRad2); and from - said first predetermined ratio( V1/V2) between said first speed and said second speed.