A barrier that prevents the heating of a space or an object by absorbing, reflecting, or dissipating external heat, especially a protective structure on a spacecraft or missile that dissipates heat on atmospheric reentry by melting and vaporizing.
Any heat-protecting device or system, esp. an ablative coating or tiles, bonded to the surface of a reentry spacecraft.
A barrier that prevents a substance from absorbing heat energy from an outside source by absorbing and dissipating, or simply reflecting, that heat. Heat shields are commonly used to protect parts of a device from heat generated by its energy source, as in isolating the cabin of a car from its motor. Many spacecraft dissipate heat generated by friction with the atmosphere upon reentry using heat shields that melt and vaporize, dissipating the energy back into the atmosphere.
(space science) A shield designed of a substance that absorbs excessive heat from an outside source by either dissipating, reflecting or simply absorbing the heat.