Laser time-transfer facility and preliminary results from the CHOMPTT CubeSat mission

The CubeSat Handling of Multisystem Precision Time-Transfer (CHOMPTT) mission is a precision timing and laser time-transfer demonstration on a CubeSat in orbit. Developed by the University of Florida in collaboration with NASA Ames Research Center, the 3U CubeSat has been in orbit for over 3 years and has attempted time-transfer operations to three satellite laser ranging (SLR) facil-ities. Additionally, the CHOMPTT CubeSat has successfully achieved one of its two primary goals, the first-ever measurement of the relative timing performance (Allan deviation) of Chip Scale Atomic Clocks (CSAC) on-orbit, while time transfer operations continue. The on-orbit performance of the CSACs and host payload is consistent with pre-flight measurements on the ground, with the CSAC timing stability exceeding the manufacturer specification by roughly a factor of three, or an Allan Deviation of 100 ps over 1 s of aver-aging time compared to a datasheet value of 300 ps over the same timeframe. This paper discusses the CHOMPTT spacecraft's perfor-mance on-orbit relative to ground experiments performed prior to launch, as well as the design and operation of the laser ranging facility and spacecraft flight operations performed during the mission's lifetime. (c) 2023 COSPAR. Published by Elsevier B.V. All rights reserved.