Loop Heat Pipes (LHPs) are robust, self-starting, and passive two-phase thermal transport devices. They utilize the latent heat of vaporization of a working fluid to transfer heat, and the surface tension forces formed in a fine-pore wick to circulate the working fluid. They are used to transport excess heat from a heat source such as payload instruments in a spacecraft to a low temperature heat sink, while maintaining the temperature within specified limits. Recent articles on LHPs published by GSFC include:

• Ku,J., Ottenstein, L, Kobel, M., Rogers, P and T. Kaya,"Temperature Oscillations in Loop Heat Pipe Operation," STAIF 2001, American Institute of Physics, Albuquerque, New Mexico, February 11-14, 2001.
• Ku, J., "Start-up Issues with Low Powers in a Loop Heat Pipe," STAIF 2001, American Institute of Phyics, Albuquerque, New Mexico, February 11-14, 2001.
• Baker, C., Butler, D., Ku, J., and E. Grob, "Acceptance Thermal Vacuum Tests of the GLAS Flight Loop Heat Pipe Systems," STAIF 2001, American Institute of Physics, Albuquerque, New Mexico, February 11-14, 2001.