Prof. Dr. Mezak Arnold Ratag, APU

Prof. Dr. Mezak Arnold Ratag, APU

Prof. Dr. Mezak Arnold Ratag, APU

Mezak A. Ratag is Professor of Astronomy & Astrophysics of the Faculty of Mathematics & Sciences at the Christian University of Indonesia in Tomohon (UKIT), where he currently serves as the President/Rector of the University. He is also a Senior Principal Research Scientist at the University. Ratag received BSc degrees in Astronomy from Bandung Institute of Technology in 1984. Dr. Ratag received his Ph.D. in Astrophysiscs from Groningen Royal University in 1991 working under the supervision of Prof. Stuart R. Pottasch. He was a researcher at the National Aeronautics & Space Institute (LAPAN) and then Head of Atmospheric Division and Climate Modelling Division. From 2004 until 2008 he became the Director for Research & Development at the National Bureau of Meteorology and Geophysics. From 1999 to 2009 he worked also as professor at Bandung Institute of Technology. His research team is responsible for the discovery of 46 new Ratag-Pottasch-Zijlstra- Menzies RPZM planetary nebula (PN) as well as 75 new Ratag-Pottasch PN. He was part of the team who discovered the OH-maser in PNe. He published also some new formulae of the ionization correction factors for argon, sulfur and neon in very low density medium. Ratag is also active in many social activities including math & science teaching for students in remote and under- developed areas. He established the Indonesia CosmoGenius education center which trains basic math and sciences for regular and olympiad students. In 2000, Dr. Ratag received the Medal for Heroic Achievements in science (Satyalancana Wirakarya) from the President of Republic of Indonesia. Research Awards from the National Institute of Sciences and the National Institute

Planetary Nebulae: the final fate of stars like our Sun

A planetary nebula (PN) is believed to be a short evolutionary phase preceeding the white dwarf phase in the late evolutionary history of stars with initial masses between 0.8 and 6 solar masses. The ‘forbidden’ natures of some of their important spectroscopic lines, make it possible for planetary nebulae to be easily observed at very large distances, and the chemical composition of the material as well as other properties of the nebulae and the central stars can be derived. In this lecture we will dicuss the recent results highlighting the importances of the knowledge of planetary nebulae for understanding not only the evolution of stars similar to our Sun but also the evolution of the Milky Way and other galaxies