NASA says its Nancy Grace Roman Space Telescope now has enough propellant for at least 22 years of science, more than double its 10-year design life. The first mid-course correction burn on August 31 was more than 99% accurate and used only about 40 pounds of fuel, against a budget of 441 pounds.
The extension comes from three sources of roughly four years each: the efficient first burn, extra propellant loaded at launch because the observatory weighed 17,760 pounds instead of the 21,605 pounds assumed, and further savings expected from a second burn and orbital insertion.
The figures are projections. The second correction is planned for later in September, and Roman is due to reach its orbit at the Sun-Earth L2 point around early December. Fuel is also not the only limit on how long the mission can operate.