A vehicle comprising: a body having a skin; a heat source; and a thermal management system comprising: a heat pipe comprising: an evaporator end and a condenser end; a vapour arranged to flow from the evaporator end to the condenser end; a working fluid arranged to flow from the condenser end to the evaporator end a first temperature sensor for measuring the temperature of the heat source; translation means for causing the heat pipe to translate from a first configuration to a second configuration in response to a control signal, wherein in the first configuration the evaporator end is arranged in proximity to the heat source and in the second configuration the evaporator end is arranged at a greater distance from the heat source than in the first configuration; and a processor arranged to receive a temperature measurement from the first temperature sensor and to generate a control signal to control the translation means to translate the heat pipe from the first configuration to the second configuration or from the second configuration to the first configuration depending on whether the temperature is respectively less than or greater than a threshold; wherein the heat pipe is arranged such that the evaporator end is arranged in proximity to the heat source to absorb heat from the heat source; and one or more heat exchangers (22a, 22b) are arranged in proximity to the condenser end and are integrated with the skin a body having a skin; a heat source; and a thermal management system comprising: a heat pipe comprising: an evaporator end and a condenser end; a vapour arranged to flow from the evaporator end to the condenser end; a working fluid arranged to flow from the condenser end to the evaporator end a first temperature sensor for measuring the temperature of the heat source; translation means for causing the heat pipe to translate from a first configuration to a second configuration in response to a control signal, wherein in the first configuration the evaporator end is arranged in proximity to the heat source and in the second configuration the evaporator end is arranged at a greater distance from the heat source than in the first configuration; and a processor arranged to receive a temperature measurement from the first temperature sensor and to generate a control signal to control the translation means to translate the heat pipe from the first configuration to the second configuration or from the second configuration to the first configuration depending on whether the temperature is respectively less than or greater than a threshold; wherein the heat pipe is arranged such that the evaporator end is arranged in proximity to the heat source to absorb heat from the heat source; and one or more heat exchangers (22a, 22b) are arranged in proximity to the condenser end and are integrated with the skin an evaporator end and a condenser end; a vapour arranged to flow from the evaporator end to the condenser end; a working fluid arranged to flow from the condenser end to the evaporator end a first temperature sensor for measuring the temperature of the heat source; translation means for causing the heat pipe to translate from a first configuration to a second configuration in response to a control signal, wherein in the first configuration the evaporator end is arranged in proximity to the heat source and in the second configuration the evaporator end is arranged at a greater distance from the heat source than in the first configuration; and a processor arranged to receive a temperature measurement from the first temperature sensor and to generate a control signal to control the translation means to translate the heat pipe from the first configuration to the second configuration or from the second configuration to the first configuration depending on whether the temperature is respectively less than or greater than a threshold; wherein the heat pipe is arranged such that the evaporator end is arranged in proximity to the heat source to absorb heat from the heat source; and one or more heat exchangers (22a, 22b) are arranged in proximity to the condenser end and are integrated with the skin