Progress

Important progress has been made along the "0123" roadmap of the TianQin Project:

Step 0

The TianQin Ranging Station has been constructed and has successfully ranged to all five retro-reflectors available on the moon in 2019.

Key reference:

Zhang et al., The facilities and performance of TianQin laser ranging station, Class.Quant.Grav. 39 (2022) 12, 125005 

Step 1

The TianQin-1 experimental satellite has been launched in December 2019 and completed operation in January 2021. The satellite successfully completed all planned tests, has improved the technology index of inertial sensing by about two orders of magnitude, and has enabled the first production of an Earth gravity model using Chinese satellite data. The mission has been given a top grade by CNSA in November 2022.

Key reference:

Luo et al., The first round result from the TianQin-1 satellite, Class.Quant.Grav. 37 (2020) 18, 185013 

Step 2

The TianQin-2 mission has been officially approved by CNSA in December 2021 and is expected to be launched in 2026.

Step 3

Various aspects of the TianQin-3 gravitational wave detection mission have been studied in detail. Issues and questions concerning the concept of a geocentric mission, and potential contribution of TianQin to gravitational wave science in the 2030s have been clarifed.

Overview of the TianQin project:

Luo et al., TianQin: a space-borne gravitational wave detector, Class.Quant.Grav. 33 (2016) 3 

Mei et al., The TianQin project: current progress on science and technology, PTEP 2021 (2021) 5, 05A107 

Luo et al., Progress of the TianQin project，e-Print: 2502.11328 [gr-qc]

TianQin science white papers:

Li et al., Gravitational wave astronomy with TianQin, Rept.Prog.Phys. 88 (2025) 5, 056901

Luo et al., Fundamental Physics and Cosmology with TianQin, e-Print: 2502.20138 [gr-qc]

Torres-Orjuela et al., Detection of astrophysical gravitational wave sources by TianQin and LISA, Sci.China Phys.Mech.Astron. 67 (2024) 5, 259511

TianQin science data simulation:

Li et al., GWSpace: a multi-mission science data simulator for space-based gravitational wave detection, e-Print: 2309.15020 [gr-qc]