Lunar Orbital VLBI Experiment: motivation, scientific purposes and status
Abstract
The Lunar Orbital VLBI Experiment (LOVEX) is a scientific component of the Chinese Lunar Exploration Project (CLEP) Chang'E-7. The spaceborne component of LOVEX is implemented onboard the relay satellite QueQiao-2, which was launched on 2024 March 20, and later placed into an elliptical selenocentric orbit. The LOVEX-specific payload consists of an X-band cryogenic receiver, a hydrogen maser frequency standard, and VLBI data formatting and acquisition electronics. Several components of the QueQiao-2 nominal onboard instrumentation, such as the 4.2-meter antenna, the data storage device, and the downlink communication system, contribute to the overall spaceborne VLBI instrumentation. This allows us to form a space radio telescope capable of co-observing with Earth-based radio telescopes in VLBI mode. In this space VLBI system, the length of the baseline extends up to approximately 380,000 km. This paper presents the LOVEX scientific objectives, architecture, instrumentation, pre-launch tests, in-flight verification and calibration, and the first in-flight detections of interferometric response (''fringes'') achieved through observations of the quasar AO 0235+164 and the Chang'E-6 orbital module, positioned at the Sun-Earth Lagrange point L2. These initial results demonstrate the successful performance of LOVEX, verifying its capability for both astronomical and spacecraft tracking observations at ultra-long VLBI baselines.
Keywords
Cite
@article{arxiv.2507.16317,
title = {Lunar Orbital VLBI Experiment: motivation, scientific purposes and status},
author = {Xiaoyu Hong and Weiren Wu and Qinghui Liu and Dengyun Yu and Chi Wang and Tao Shuai and Weiye Zhong and Renjie Zhu and Yonghui Xie and Lihua Zhang and Liang Xiong and Yuhua Tang and Yongliao Zou and Haitao Li and Guangli Wang and Jianfeng Xie and Changbin Xue and Hao Geng and Juan Zhang and Xiaojing Wu and Yong Huang and Weimin Zheng and Lei Liu and Fang Wu and Xiuzhong Zhang and Tao An and Xiaolong Yang and Fengxian Tong and Leonid I. Gurvits and Yong Zheng and Minfeng Gu and Xiaofei Ma and Liang Li and Peijia Li and Shanshan Zhao and Ping Rui and Luojing Chen and Guohui Chen and Ke Li and Chao Zhang and Yuanqi Liu and Yongchen Jiang and Jinqing Wang and Wenbin Wang and Yan Sun and Longfei Hao and Lang Cui and Dongrong Jiang and Zhihan Qian and Shuhua Ye},
journal= {arXiv preprint arXiv:2507.16317},
year = {2025}
}
Comments
Accepted for publication in Science China: Physics, Mechanics & Astronomy