Up to now , most stellar-mass black holes were discovered in X-ray emitting binaries , in which the black holes are formed through a common-envelope evolution .
Here we give evidence for the presence of a massive black hole candidate as a tertiary companion in the massive eclipsing binary V Puppis .
We found that the orbital period of this short-period binary ( P=1.45 days ) shows a periodic variation while it undergoes a long-term increase .
The cyclic period oscillation can be interpreted by the light-travel time effect via the presence of a third body with a mass no less than 10.4 solar mass .
However , no spectral lines of the third body were discovered indicating that it is a massive black hole candidate .
The black hole candidate may correspond to the weak X-ray source close to V Puppis discovered by Uhuru , Copernicus , and ROSAT satellites produced by accreting materials from the massive binary via stellar wind .
The circumstellar matter with many heavy elements around this binary may be formed by the supernova explosion of the progenitor of the massive black hole .
All of the observations suggest that a massive black hole is orbiting the massive close binary V Puppis with a period of 5.47 years .
Meanwhile , we found the central close binary is undergoing slow mass transfer from the secondary to the primary star on a nuclear time scale of the secondary component , revealing that the system has passed through a rapid mass-transfer stage .