September 8, 2021

ACT Viper400x275NASA has awarded Advanced Cooling Technologies (ACT) a $3.7 million contract to finalize the design and fabricate the flight thermal control system for the Volatiles Investigating Polar Exploration Rover (VIPER), which will explore the South Pole of the Moon.

VIPER, part of the Artemis mission, is a golf cart-sized rover that will roam several miles across the South Pole of the Moon to get a close-up view of the location and concentration of ice during an approximate 100-day mission. The Artemis program aims to accomplish many firsts for NASA and the global space community. The VIPER is NASA’s first lunar robotic rover, and is the first resource-mapping mission on the surface of another celestial body. The thermal control system developed jointly by ACT and NASA will be the first to maintain operation for a 100-day mission while in shadowed conditions.

“It’s exciting to demonstrate some of the best passive thermal management solutions on such an important mission,” said Bill Anderson, chief engineer at ACT.

For the contract, ACT said it will deliver a combination of high-performance, passive thermal technologies specifically designed to meet the challenges associated with a long-term lunar mission, including:

  • Loop Heat Pipes (LHPs) with integral Thermal Control Valves (TCVs)
  • External Ammonia Constant Conductance Heat Pipes (CCHPs)
  • Honeycomb Radiator Panels with embedded CCHPs.

Why this matters

Surviving in subzero temperatures is not only important for robotics equipment, but also for the possibility of establishing a lunar colony and Mars colony in the future. In addition, data acquired through these missions will likely be applied to robotics back on Earth.

In addition to the flight articles, ACT said it will provide system and sub-system level thermal analytics, verification, and thermal testing in coordination with the teams at NASA’s Johnson Space Center in Houston, and NASA’s Marshall Space Flight Center in Huntsville, Alabama. All flight articles will be delivered by June 2022 in order to meet NASA’s critical launch schedule, ACT said. 

The company added that operating in shadowed conditions is one of the most challenging aspects of the VIPER mission. Due to the slow rotation of the lunar surface relative to the sun, the environmental temperature drops to below 100K (-280 F) for approximately 14 Earth days. This condition has been avoided in the past, including the Apollo mission, which landed in the lunar morning. To enable long-duration science missions on the lunar surface, it is necessary to maintain the electronics above survival temperatures while in shadows, ACT said. The hardware it is developing reduces the amount of survival heat needed by an order of magnitude – from 100s of Watts to 10s. The company said this significantly reduces the amount of solar power generation and mass required on the rover, which will extend its life and functionality.

The collaboration between NASA and ACT goes back more than a decade, nearly to ACT’s formation as a company in 2003. Many of the mission-critical technologies controlling the temperature on VIPER were developed through the Small Business Innovation Research (SBIR) program, and stemmed from original development programs more than a decade ago.

“NASA and ACT have been working for many years developing these technologies, and the team is thrilled to get the chance to build the products that will actually fly to the Moon,” said Ryan Spangler, lead aerospace engineer at ACT.

For more details on ACT and its thermal technologies, visit its website here.

Related video: