We analyzed high accuracy time delays of laser signals sent from the Earth to the retroreflector arrays on the Moon in conjunction with several other sets of solar‐system astrometric data. Using especially the lunar laser ranging data obtained from the Apache Point Observatory telescope site in New Mexico and the Apollo 11 and Apollo 14 retroreflectors on the Moon, we have set a bound on their relative motion along the connecting great circle of 4 mm/yr over a 14‐year period.
Fifteen Years of Millimeter Accuracy Lunar Laser Ranging with APOLLO: Data Set Characterization
We present data from the Apache Point Observatory Lunar Laser-ranging Operation (APOLLO) covering the 15 yr span from 2006 April through the end of 2020. APOLLO measures the Earth–Moon separation by recording the round-trip travel time of photons from the Apache Point Observatory to five retro-reflector arrays on the Moon. The APOLLO data set, combined with the 50 yr archive of measurements from other lunar laser ranging (LLR) stations, can be used to probe fundamental physics such as gravity and Lorentz symmetry, as well as properties of the Moon itself. We show that range measurements performed by APOLLO since 2006 have a median nightly accuracy of 1.7 mm, which is significantly better than other LLR stations.
more » « less- NSF-PAR ID:
- 10471139
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Publications of the Astronomical Society of the Pacific
- Volume:
- 135
- Issue:
- 1052
- ISSN:
- 0004-6280
- Format(s):
- Medium: X Size: Article No. 104504
- Size(s):
- ["Article No. 104504"]
- Sponsoring Org:
- National Science Foundation
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