As an astronaut traverses the lunar South Pole, tribocharging from walking on the lunar surface and plasma charging from the ambient plasma generate electric charge on the spacesuit. This problem is severely compounded when entering lunar shadows and Permanently Shadowed Regions (PSRs). In these dark zones, the spacesuit can buildup a substantial negative potential due to a lack of ambient ion flux and the absence of photoelectron emission to balance ambient electron collection.
The risk occurs when an astronaut returns to the spacecraft. Because the lunar surface lacks a natural environmental mechanism to bleed the charge accumulated on spacesuit away, the astronaut may become a walking, high voltage capacitor.
In the sunlit region, the stationary lander will hold slightly positive electrical potential. When a highly negatively-charged astronaut approaches the vehicle, the extreme voltage differential can trigger electrostatic discharge (an instantaneous electrical arc, or a spark) during physical contact. A rapid discharge from the astronaut to the lander risks degrading vital suit layers, damaging sensitive suit electronics, threatening the oxygen-rich environment inside the suit, and delivering dangerous electrical shocks to the crew.
Through the Lunar Grounding Challenge, NASA is seeking innovative designs and operational solutions to provide a lunar bringing to equilibrium capability to safely discharge a suited astronaut from high triboelectric charge buildup during lunar surface EVAs in the South Pole. This challenge seeks innovative concepts for an Electrostatic Discharge (ESD) mitigation solution to neutralize the astronaut in a safe and timely manner under this extreme charge differential before astronauts directly interact with the lander.
Award: Up to $150,000 in prizes
Challenge Open Date: October 5, 2026
Submissions Close Date: January 15, 2027
For more information, visit: https://work.crowdplat.com/challenge/lunar-grounding-challenge
Source: NASA