P. Chernyaha's scientific career began after defending his PhD (Candidate of Sciences) dissertation, Determining Satellite Refraction Considering the State of the Atmosphere, and earning in 1978 the Candidate of Sciences degree. In 1982 he was conferred the position of Associate Professor.
His further research at Ukrainian nuclear power plants and international experience gained at European Geophysics congresses (in Vienna in 1997, Nice in 1998, the Hague in 1999, Poland in 1997, 1998, 1999 and Croatia in 2001) helped him complete his Doctorate dissertation, Geodesic monitoring of the premises of nuclear power plants: theory and practice, and successfully defend it in 2000, with the position of Professor being conferred upon him.
Throughout his scientific career Petro Chernyaha published over 200 scientific, educational and methodological works and made an invention.
Petro Chernyaha’s was a member of editorial boards of six professional scientific journals, a member of specialized academic dissertation boards at the Kyiv National Construction and Architecture University and the National Lviv Polytechnical University. He also served on the methodological panel on Geodesy, Mapping and Land Utilization, as well as on the committee developing education standards in this subject. And he was a full member of the Ukrainian Academies of Construction and Higher Education Sciences.
Of particular value for students' educational life was the Research Geodynamics and Geo-information Systems laboratory established by P. Chernyaha at the National University of Water Economy and Management of Natural Recourses. This laboratory was engaged in research in the sphere of land relations reforms, mathematical modeling of geodynamic processes, considering the tropospheric, ionospheric and electro-optical refraction in geodesic surveying and GPS observation.
P. Chernyaha also established a research institution which made forecasts of territorial development considering the functional properties of territories and the impact of geodynamic processes. This school gained wide recognition in the academic world. Nearly twenty Candidate dissertations and one Doctorate dissertation were defended under his supervision there.
Petro Chernyaha was credited by many scientists, teachers and students with making an invaluable contribution to the development of Geodesy and Land Utilization in Ukraine.
In November 2014 an annual national scientific conference on Geodesy, Land Utilization and Management of Natural Resources was initiated posthumously in commemoration of P. Chernyaha at the National University of Water Economy and Management of Natural Recourses in Rivne, where a memorial plaque was unveiled and a classroom was named in his honour. In his lifetime P. Chernyaha received numerous awards and titles from various institutions and bodies or government.