As NASA looks to explore the Moon, Mars, and beyond, researchers must develop materials capable of withstanding the extreme temperatures found in space and on other planets and their moons. In frigid conditions, rubber can shatter like glass, circuit boards may fail, and electrical connections can freeze and fracture.\u00a0<\/p>\n
Gaining a deeper understanding of how materials respond to these temperature extremes is critical \u2014 especially as NASA looks to build its Moon Base<\/a> at the lunar South Pole, where surface temperatures swing dramatically from blistering heat during the day to bitter cold at night. Researchers developed a ground-breaking method for testing how materials hold up in the extreme cold of space. Engineers at NASA\u2019s Glenn Research Center in Cleveland invented the Lunar Environment Structural Test Rig (LESTR), a machine that can test materials, electronics, and other flight hardware at temperatures as low as 40 Kelvin, or about \u2013388 degrees Fahrenheit.\u00a0<\/p>\n \u201cJust as no building ever gets built without knowing exactly how the construction materials behave, no space mission is complete without a robust structural design that hinges on knowing how the materials used within it behave,\u201d\u00a0said Ariel\u00a0Dimston, technical lead for LESTR at NASA Glenn.\u00a0<\/p>\n Traditionally,\u00a0NASA\u00a0has used a process that involves super-cold liquids \u2014 called liquid cryogens\u00a0\u2014\u00a0to test\u00a0how\u00a0materials\u00a0respond to extreme cold.\u00a0These liquids, like nitrogen, hydrogen, and helium, are\u00a0some of the coldest materials on\u00a0Earth and are stored in\u00a0specialized tanks.\u00a0Engineers use them to\u00a0chill\u00a0materials\u00a0during testing and collect data to see\u00a0how\u00a0they perform.\u00a0\u00a0\u00a0\u00a0<\/p>\n \u201cWhat makes LESTR special is that the entire rig operates in a completely dry vacuum:\u00a0no liquid nitrogen,\u00a0no liquid helium,\u00a0no liquid anything,\u201d\u00a0Dimston\u00a0said. \u201cThis is the first mechanical test rig that escapes from all of the challenges involved with\u00a0cryogenic fluids.\u201d\u00a0<\/p>\n LESTR\u00a0takes\u00a0a new approach\u00a0by using a high-powered refrigerator, called a\u00a0cryocooler,\u00a0to remove heat\u00a0without using any liquid at all. This\u00a0creates\u00a0the first \u201cdry\u201d cryogenic\u00a0test\u00a0environment within the mechanical testing industry.\u00a0This new\u00a0test rig is safer\u00a0and\u00a0more affordable\u00a0than\u00a0traditional methods\u00a0and\u00a0allows scientists to test materials\u00a0at a much wider range of temperatures,\u00a0Dimston\u00a0said.\u00a0<\/p>\n \u201cBy leaving behind the liquid cryogen, you no longer need specialized handling equipment such as\u00a0dewers, wet heaters,\u00a0nor valves,\u201d\u00a0Dimston\u00a0said. \u201cYou no longer require oxygen displacement sensors and other safety systems that add time, complexity, and cost\u00a0to\u00a0the process since without these cryogens they are no longer needed.\u201d\u00a0<\/p>\n Dimston\u00a0and his team are working with\u00a0NASA\u00a0programs and projects to\u00a0put materials through their\u00a0paces\u00a0using the new apparatus.\u00a0The team\u00a0has\u00a0been testing\u00a0yarns that may someday be woven into fabrics used for next-generation spacesuits and is looking to develop advanced materials for\u00a0rover tires, including a new metal\u00a0that can return to its original shape after being bent, stretched, heated, and cooled. This\u00a0shape memory alloy\u00a0technology could help future rovers travel<\/a> across the uneven, rocky surfaces of the Moon and Mars without the risk of flat tires.<\/p>\n NASA researchers spent more than two years designing and building the first version of the technology \u2014 LESTR 1 \u2014 and\u00a0are\u00a0currently building its twin, LESTR 2. In a partnership with Fort Wayne Metals, NASA delivered LESTR 1 to the\u00a0company\u2019s facility in\u00a0Fort Wayne,\u00a0Indiana, where experts there will use it to test shape memory alloy material for\u00a0the\u00a0extreme temperatures present on the Moon.\u00a0<\/p>\n \u201cWe are working to develop a next-generation shape memory alloy that is capable of functioning at temperatures down to 40 Kelvin, one of the coldest regions we could go to with rover capability,\u201d said Dr. Santo Padula II, principal investigator for LESTR at NASA Glenn. \u201cWith this rig, we can test\u00a0how\u00a0shape memory alloys\u00a0will behave in\u00a0the coldest areas of the Moon and Mars.\u00a0That will be\u00a0a very big\u00a0day for us:\u00a0to be able to see what its properties look like at such low temperatures \u2014 something\u00a0we\u2019ve\u00a0never seen before.\u201d\u00a0<\/p>\n Beyond LESTR,\u00a0NASA\u00a0Glenn\u00a0has\u00a0other\u00a0world-class ground test facilities<\/a>\u00a0that mimic environments like the vacuum of space, the microgravity aboard the International Space Station, the\u00a0sulfuric pressure cooker that is Venus, or the\u00a0terrain\u00a0of the Moon and Mars.\u00a0\u00a0<\/p>\n Glenn leads the agency in\u00a0both\u00a0advanced\u00a0materials testing and\u00a0in-space\u00a0cryogenic fluid management<\/a>, playing a vital role in developing technologies for future space exploration.\u00a0\u00a0<\/p>\n