Ultra-Low-Frequency Radio Astronomy Observations from a Selenocentric Orbit: first results of the Longjiang-2 experiment

Jingye Yan; Ji Wu; Leonid I. Gurvits; Lin Wu; Li Deng; Fei Zhao; Li Zhou; Ailan Lan; Wenjie Fan; Min Yi; Yang Yang; Zhen Yang; Mingchuan Wei; Jinsheng Guo; Shi Qiu; Fan Wu; Chaoran Hu; Xuelei Chen; Hanna Rothkaehl; Marek Morawski

doi:10.1007/s10686-022-09887-0

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arXiv · 2212.09590

Ultra-Low-Frequency Radio Astronomy Observations from a Selenocentric Orbit: first results of the Longjiang-2 experiment

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Abstract

This paper introduces the first results of observations with the Ultra-Long-Wavelength (ULW) -- Low Frequency Interferometer and Spectrometer (LFIS) on board the selenocentric satellite Longjiang-2. We present a brief description of the satellite and focus on the LFIS payload. The in-orbit commissioning confirmed a reliable operational status of the instrumentation. We also present results of a transition observation, which offers unique measurements on several novel aspects. We estimate the RFI suppression required for such a radio astronomy instrumentation at the Moon distances from Earth to be of the order of 80 dB. We analyse a method of separating Earth- and satellite-originated radio frequency interference (RFI). It is found that the RFI level at frequencies lower than a few MHz is smaller than the receiver noise floor.

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Jingye Yan, Ji Wu, Leonid I. Gurvits, Lin Wu, Li Deng, Fei Zhao, Li Zhou, Ailan Lan, Wenjie Fan, Min Yi, Yang Yang, Zhen Yang, Mingchuan Wei, Jinsheng Guo, Shi Qiu, Fan Wu, Chaoran Hu, Xuelei Chen, Hanna Rothkaehl, Marek Morawski. 2022-12-19. Ultra-Low-Frequency Radio Astronomy Observations from a Selenocentric Orbit: first results of the Longjiang-2 experiment. https://doi.org/10.1007/s10686-022-09887-0

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