Hakkı Ögelman

Hakkı Boran Ögelman (July 8, 1940 – September 4, 2011) was a Turkish physicist and astrophysicist.

He was an expert on gamma ray astronomy, the physics of neutron stars, and solar energy and worked on several key topics in modern astrophysics.

He made many contributions to high energy astrophysics.

In his early professional career he engaged in the SAS-II Small Gamma Ray Astronomy Satellite experiment development, data analysis, and first detection and imaging of our universe in gamma rays with his NASA colleagues, as well as in other fields of physics.

His main interests in the field of astrophysics were the study of gamma ray astronomy and compact objects such as neutron stars and pulsars.

Ögelman worked at NASA Goddard Space Flight Center, Middle East Technical University (METU) in Ankara, Turkey, Çukurova University in Adana, Turkey, Max Planck Institute (MPI) at Garching, Germany and the University of Wisconsin.

Hakkı Ögelman was born in Ankara, Turkey, on July 8, 1940.

His father was Salehettin Ögelman, a lawyer, and his mother was Vedya Özlem Ögelman, a schoolteacher.

Hakkı Ögelman attended English-language Robert College in Istanbul, receiving his baccalaureate in 1957, then went to the U.S. to further his education.

He received his B.A. in physics from DePauw University in June 1960 and his M.Sc.

and Ph.D. from Cornell University in 1963 and 1966, respectively.

He married a DePauw classmate, Ivy White.

After his 1966 graduation from Cornell, Ögelman did one year of postdoctoral research at the University of Sydney, Australia.

He then worked at Goddard Space Flight Center from September 1967 to January 1970 as National Academy of Sciences Research Associate.

In February 1970 Ögelman decided to return to Turkey, so that he could contribute his experimental research and teaching capabilities to his country.

He was hired as an associate professor in the Middle East Technical University (METU) Physics Department, and was appointed department chairman that same year.

He started an experimental High Energy Astrophysics group specializing in gamma ray astronomy—at the time, a fledgling new field—and took on graduate students for the group's M.Sc.

and Ph.D. programs.

Ögelman also started a new solar energy group to train graduate students to address Turkey's energy needs.

Additionally, he worked with the METU's Carbon-14 Dating Group, led by Yeter Goksu, a physics department colleague who would later become his second wife.

During Ögelman's time at METU, his astrophysics group's major projects used data of NASA's SAS-II (Second Small Astronomy Satellite) gamma ray telescope.

With this group and his former NASA colleagues, Ögelman co-authored several critical papers on gamma ray astronomy published using the SAS II data.

Their work covered the premiere satellite based detection of gamma rays from celestial objects, the observation of galactic gamma ray emission from compact objects including the Crab Nebula, and the discovery of Geminga.

The SAS II gamma ray telescope's successful results during the 1970s brought gamma ray astronomy of age and established it as the newest astrophysics field.

Under Ögelman's leadership, his group carried out actual data analysis at METU with graduate and undergraduate students, and contributed significantly to the SAS II project's success.

By that time the once-fledgling field of gamma ray astronomy had since grown into a major science utilizing numerous other space-based and balloon-born telescopes, and many important discoveries have been made extending astronomy to the high energy region.

In 1973 Ögelman took a leave of absence from METU to complete his army service.

In 1974 he took a sabbatical leave of absence to serve as a National Academy of Sciences Senior Research Associate at the Goddard Space Flight Center in Greenbelt, Maryland, working with his colleagues at NASA's Gamma Ray Astronomy Group led by Dr. Carl E. Fichtel.

Ögelman returned to METU in 1975, becoming a full professor in 1976.

In 1977, at the invitation of the president of Çukurova University (CÜ) in Adana, Turkey, Ögelman took another leave of absence and with three of his METU colleagues (and, later, some of his graduate and post graduate students from METU, who formed the core of the new Physics Department) moved to CÜ to start and establish its Faculty of Arts and Sciences.

Becoming the founding Dean of the faculty, he decided to take students without delay, and the group started classes in barracks.

Eventually, Ögelman arranged for funding from the Ford Foundation and the USAID to start a modern research laboratory in the campus.

He also took an interest in the local economy and needs of the people, and encouraged the faculty to research in fields with most benefit to the region.

One of the most important topics to address at that time concerning physics was Turkish society's energy needs.

Ögelman gave priority to solar energy research in the Physics Department because in the Cukurova region there is plenty of sunshine throughout the year.

To this end, as he had at METU, he started research in solar energy, building Turkey's first energy efficient solar house and a solar pond.

Ögelman left CÜ in 1982 to return to METU but continued working with his previous students as colleagues on astrophysics.

From July 1983 to July 1985, Ögelman again took a leave of absence from METU, spending the period as a guest scientist at the Max Planck Institute for Extraterrestrial Physics (MPE) in Munich, Germany.

Ögelman then became a resident scientist at MPE and worked there from July 1985 to January 1991.

He started working on X-ray data of the Einstein and Exosat satellites.