  Coalescing supermassive black hole binaries (SMBHBs) are the primary source
candidates for low frequency gravitational wave (GW) detections, which could
bring us deep insights into galaxy evolutions over cosmic time and violent
processes of spacetime dynamics. Promising candidates had been found based on
optical and X-ray observations, which claims for new and ready-to-use GW
detection approaches before the operations of space-borne antennas. We show
that, satellite laser ranging (SLR) missions could serve as probes of
coalescing SMBHBs through the GW-induced resonant effects. Lasting and
characteristic imprints caused by such resonances in the residual distances or
accelerations from SLR measurements are studied, and the detection SNR is
analyzed with both the current and future improved ranging precisions. Within
redshift $z \sim 1$, the threshold SNR=5 requires 1-2 years of accumulated data
for the current precision and months of data for improved precision, which are
workable for the data processing of SLR missions. Meanwhile, joint detections
with multiple SLR missions could further improve the total SNR and the
confidence level. Such a detection scheme could fulfill the requirement of a
tentative SMBHB probe during the preparing stage of LISA and Taiji, and it
requires no further investment to any new and advanced facilities. It is also
worthwhile to look back and re-process the archived data from the past decades,
in where resonant signals from SMBHBs might be hidden.

General Relativity and Quantum Cosmology;Instrumentation and Methods for Astrophysics;Instrumentation and Detectors;Space Physics