Astronomy Day is annually celebrated in Armenia on September 18. This observance was established by the government of Armenia to commemorate birthday of Victor Ambartsumian, an outstanding Armenian scientist, founder of theoretical astrophysics and national hero in Armenia Byurakan Astrophysical Observatory reports.

Victor Ambartsumian was born on September 18, 1908. He obtained a diploma in physics and mathematics and continued studies at Pulkovo Observatory, the principal astronomical observatory of the Russian Academy of Science. In 1926 he published his first scientific article. He became a prominent person in physics in 1929, when he published a demonstration, proving that atomic nuclei couldn't be made from protons and electrons.

Much of his research was dedicated to the evolution of galaxies. One of his groundbreaking works was a lecture concerning the explosion of nuclei of the galaxies, the source said.