Yurij Nikolaevich Efremov (b. 1937) is a leading research scientist at the Sternberg Astronomical Institute, Moscow University. His works on variable stars and star-formation regions are well known. He discovered the period-age relationship for cepheids and created the concept of large complexes of young stars.
Discovered on 28-9-1973 in Nauchnyj by Chernykh, N. S.