On January 15, 2025, a precision prism reflector devised by UMD physicists once again headed to the moon, continuing a tradition begun in 1969, when the Apollo 11 crew positioned still-functioning Lunar Laser Ranging Retroreflectors (LLRR).
A single 10 cm diameter corner cube retroreflector. Credit: Doug Currie
One of the physicists responsible for the original retroreflectors, Doug Currie, is the PI for the current version, Next Generation Lunar Retroreflectors (NGLR). Using intense, brief lasers pulses, scientists on Earth will reflect light off the instrument, allowing measurements of the earth-moon distance to within 1 mm of accuracy. Such precision will allow better understanding of the moon’s liquid cor
A SpaceX Falcon 9 rocket carrying Firefly Aerospace’s Blue Ghost Mission One lander on January 15, 2024. Credit: NASA/Frank Michauxe and of general relativity.
Currie’s proposal was accepted as part of NASA’s Commercial Lunar Payload Services (CLPS) project, utilizing partnerships with private industry to facilitate space launches. Blue Ghost Mission 1 by Firefly Aerospace launched at 1:11 a.m. on January 15 aboard a SpaceX Falcon 9 rocket from NASA’ Kennedy Space Center in Florida, with NGLR-1 and nine other experiments. The lunar landing is scheduled for March 2.
Currie’s storied career and the preparation for the NGLR were detailed in the September 2024 issue of Terp magazine.
He was a UMD Assistant Professor, working with LLRR PI Professor Carroll Alley, at the time of the historic first venture of humans to the moon. In 2019, he was interviewed on the 50th anniversary of Apollo 11, and was also selected for further work on retroreflectors. While the Apollo 11 retroreflectors were an array of small precision mirrors, the NGLR-1 is is a single 10 cm diameter corner cube retroreflector.
In addition to Currie, the UMD team on NGLR-1 included co-PI Drew Baden, deputy PI Dennis Wellnitz, Project Manager Ruth Chiang Carter and researchers Martin Peckerar, Chensheng Wu and Laila Wise.
Liftoff occurs at 43:01.