Next Generation Lunar Retroreflector (NGLR)

Blue Ghost Mission 1 · landed · NASA payload

A single 10 cm solid fused-silica corner-cube retroreflector in a thermally isolating housing, on the lander's antenna arm. Laser stations on Earth bounce pulses off it to measure the Earth-Moon distance to about a millimeter, for lunar interior science, the lunar coordinate system and tests of gravity.

PI: Douglas G. Currie (University of Maryland, professor emeritus)
Built by: University of Maryland, College Park (Physics); NASA Marshall oversaw the project for CLPS (university)

Technology	passive laser retroreflector (lunar laser ranging)
Moon Base need	#0101 (The study's reading. NASA says NGLR will set lunar fiducial markers for future missions to map to and locate sites, and the ranging station calls its data essential to the lunar reference frames used for positioning and navigation. That bears on gap #0101 (lunar PNT) as infrastructure for the reference frame, not as a navigation system. Its main purpose is science (lunar interior, general relativity).)
Route onto CLPS	LSITP; Lunar Surface Instrument and Technology Payloads: one of 12 payloads NASA selected on 1 July 2019 (release 19-053). NASA Marshall signed the contract with the University of Maryland on 12 Nov 2019. Named on Firefly's TO 19D when NASA awarded it on 4 Feb 2021.; 2019-07-01
Timeline	first funding 2004 (design work begins; funder not stated); first flight test not in public sources; selected 2019-07-01 (LSITP); contract signed 2019-11-12; named on TO 19D on 2021-02-04; launch 2025-01-15; landing 2025-03-02
On the Moon	operated as planned
FO	none

Flights before the Moon

None found in the public sources.

Heritage hardware

• design heritage (Apollo laser ranging retroreflector arrays): The optical design is inherited from the Apollo arrays, which the PI helped design in 1969 and which flew on Apollo 11, 14 and 15. NGLR replaces Apollo's many 38 mm cubes with one 10 cm cube, so lunar librations no longer smear the return. No earlier flight of an NGLR was found; the team says the first one flew on Blue Ghost.

"These instruments share a common optics design [1], inherited from Apollo LRAs"
— NTRS 20210025424

"Dr. Currie helped to design the three still-in-use lunar instruments placed on the Moon by Apollo Missions 11, 14, and 15."
— NGLR: Next Generation Lunar Retroreflector, University of Maryland Physics; text extracted from t…, UMD NGLR page

"The first NGLR (with fixed pointing) will be launched with a NASA-CLPS mission"
— NTRS 20210025424, section IV

• shared design (MoonLIGHT, INFN, later): Italy's INFN-LNF MoonLIGHT reflector, funded by ESA and ASI and manifested on IM-3, shares NGLR's design. It flies after NGLR, so it is a sister unit, not heritage for NGLR.

"shares its design with the Next Generation Laser Retroreflector NGLR from UMD"
— CP-11 Science Payloads - NASA Science

Funding before the lunar flight

• Design work on a 10 cm retroreflector since 2004 (UMD, with INFN-LNF in Italy); who funded it before 2019 is not stated. (not in public sources; 2004-2019): amount not in public sources

"Starting in 2004 when NASA decided to return to the Moon, Professor Currie has been pursuing the design of a Cube Corner Retroreflector (CCR) of 10 cm aperture"
— NGLR: Next Generation Lunar Retroreflector, University of Maryland Physics; text extracted from t…, UMD NGLR page, background

• LSITP contract from NASA Marshall to the University of Maryland (80MSFC20C0012), the flight unit. The team's white paper cites the same contract. Linked by name. (SMD LSITP; 2019-11-12 to 2023-12-02): $2,653,770

"NEXT GENERATION LUNAR RETROREFLECTORS (NGLR)"
— USAspending.gov, award 80MSFC20C0012, description; obligated 2653770.0

"Next Generation Laser Retroreflector (NGLR) by UMD, funded by NASA"
— NTRS 20210025424, footnote 1

How it got onto CLPS

"NGLR will serve as a target for lasers on Earth to precisely measure the Earth-Moon distance."
— NASA Selects 12 New Lunar Science, Technology Investigations - NASA, release 19-053, 1 Jul 2019

"On July 1, 2019, NASA selected the University of Maryland, College Park (UMD)"
— NGLR: Next Generation Lunar Retroreflector, University of Maryland Physics; text extracted from t…, UMD NGLR page

"NEXT GENERATION LUNAR RETROREFLECTORS (NGLR)"
— USAspending.gov, award 80MSFC20C0012, description; signed 2019-11-12, NASA Marshall

On the Moon

Grasse (France) got first returns on 3 March, Wettzell (Germany) on 4 March, and Apache Point (New Mexico) on 20 March. Precision was about 0.8-1.1 mm, and the return rate matched the Apollo 11 array. The team says NGLR-1 reached TRL 9. Lunar Laser Ranging stations keep ranging to it.

"successfully reflected and returned laser light from two Lunar Laser Ranging Observatories"
— NASA Science Continues After Firefly’s First Moon Mission Concludes - NASA

"This analysis then led to a precision in the Wettzell measurements, of 0.79 and 1.14 mm."
— NGLR: Next Generation Lunar Retroreflector, University of Maryland Physics; text extracted from t…, UMD NGLR page

"The team at Apache Point located the new retroreflector with their laser on March 20 and has continued ranging to it ever since."
— APO, NMSU researchers detect new laser reflector on moon with amazing precision, NMSU news, 4 Jun 2025

FO's role

Grade: none. No FO flight of NGLR or its University of Maryland team was found. A passive reflector gains little from a suborbital flight, and the team describes only ground development. The study's earlier traceback grade (none found) stands.

"The Next Generation Lunar Retroreflector successfully reflected and returned laser light"
— earlier finding of this study (not a public source)

Who built it

"Lead Development Organization: University of Maryland"
— TO19D Science Payloads - NASA Science

"Payload PI: Dr. Douglas Currie"
— TO19D Science Payloads - NASA Science

"NASA Marshall Space Flight Center oversees implementation of the NGLR project at UMD"
— NGLR: Next Generation Lunar Retroreflector, University of Maryland Physics; text extracted from t…, UMD NGLR page

Moon Base need

"NGLR will establish lunar fiducial markers that will allow for current and future missions to precisely map to and locate specific areas of the Moon."
— TO19D Science Payloads - NASA Science

"Apache Point produces the data used to realize the lunar reference frames that are essential for positioning and navigation application on and around the moon."
— APO, NMSU researchers detect new laser reflector on moon with amazing precision, NMSU news, 4 Jun 2025

"ESDMD #0101: Positioning, Navigation, and Timing for Lunar Surface Extreme Environments"
— Moon to Mars knowledge base: ESDMD #0101: Positioning, Navigation, and Timing for Lunar Surface Extreme Environments, title

Open questions

• Who funded NGLR's design and the 10 cm reflector manufacturing work from 2004 to 2019? Not in public sources.
• Ground tests (thermal-vacuum and optical) before delivery: which facilities, and when? Not in the sources read here.