When Intuitive Machines’ Nova-C lunar lander lifts off on February 14, it would carry a brand new new gas gauge developed by NASA that may measure cryogenic propellants within the booster tanks utilizing radio waves.
Measuring the quantity of liquid in a tank on Earth is about as straightforward to unravel an issue as there may be. You possibly can stick a dipstick in it or you’ll be able to arrange a easy mechanism with a float and a gauge marked E by way of F. In area, issues are greater than a little bit sophisticated. Since there is no such thing as a gravity to tug the liquid to the underside of the tank, it floats round and sticks to the edges of the tank because of floor stress.
Engineers can estimate how a lot propellant a spacecraft has left by realizing the unique payload mass and subtracting how a lot was used within the thrusters. Nevertheless, cryogenic fuels are likely to boil away over time and blow overboard, making the estimates a bit ‘iffy’. That is particularly an issue with long-distance interplanetary missions that may final years.
To get round this, NASA examined a brand new methodology known as a Radio Frequency Mass Gauge (RFMG), which estimates how a lot cryogenic liquid there may be through the use of an antenna put in within the tank. This antenna measures how the liquid interacts with the pure electromagnetic resonances of the tank partitions and compares this with a database. With correct calculations it’s potential to estimate the quantity of liquid inside a couple of share factors.
To date, the RFMG has been examined on plane flying on parabolic trajectories to create short-lived intervals of weightlessness, and on board the Worldwide House Station (ISS). Now it has been put in aboard the Nova-C lunar lander for a discipline take a look at that NASA engineers can examine to floor simulations and former exams.
“Due to the very small quantity of gravity, fluid doesn’t settle to the underside of propellant tanks, however sticks to the partitions and will be wherever inside,” stated Lauren Ameen, deputy supervisor of the Cryogenic Fluid Administration Portfolio Mission Workplace at NASA’s Glenn Analysis Middle in Cleveland. “That makes it actually difficult to grasp how a lot propellant you will have in your tank, which is essential for maximizing your mission length and planning how a lot to launch with.”