Arved-Ervin Sapar
Arved-Ervin Sapar | |
|---|---|
 Sapar near Tõravere Observatory, 2008 | |
| Born | 7 February 1933 Paatna, Rakvere Parish (Virumaa), Estonia |
| Died | 1 December 2021 Tartu, Estonia |
| Citizenship | Estonian |
| Alma mater | University of Tartu |
| Known for | Theoretical work on stellar atmospheres and winds; analytical solutions in cosmological models |
| Awards | Order of the White Star, 4th Class (2006); Estonian Academy of Sciences Medal (1986) |
| Scientific career | |
| Fields | Astrophysics, Cosmology |
| Institutions | Tartu Observatory |
Arved-Ervin Sapar (7 February 1933 – 1 December 2021) was an Estonian theoretical astrophysicist and cosmologist. He was elected a member of the Estonian Academy of Sciences in 1990 and worked for most of his career at the institutions that evolved into the Tartu Observatory.[1][2][3]
Independent obituaries in Estonia’s cultural weekly Sirp and public broadcaster Eesti Rahvusringhääling described his long-running leadership roles in stellar-atmosphere research organizations in the late Soviet period and his continued work at Tõravere after Estonia regained independence.[4][5]
Early life and education
Sapar was born in Paatna village, Rakvere Parish (historically, Virumaa). He completed secondary school in Rakvere and graduated from the University of Tartu in 1957, specializing in theoretical physics.[3][2] He undertook postgraduate research (aspirantura) at the Institute of Physics and Astronomy of the Estonian SSR Academy of Sciences and defended a кандидат (Candidate of Sciences) dissertation in cosmology in 1965 at the University of Tartu.[2][3] In 1989 he received the degree of Doctor of Physical and Mathematical Sciences at Leningrad State University for work on non-equilibrium statistical thermodynamics of stellar atmospheres and the study of hot-star spectra.[2]
Career
From 1957 Sapar worked at the Institute of Physics and Astronomy (and successor organizations), progressing from junior researcher to senior researcher and head of the theoretical astrophysics sector; after institutional reorganizations he continued in comparable roles at the institute that later became the Tartu Observatory, remaining research-active into the 2010s.[2][3] The Estonian Academy of Sciences lists his election to the academy in 1990 (astronomy and physics section).[1]
Research
According to Academy and university profiles, Sapar’s research covered cosmology and the theory of stellar atmospheres, including radiative transfer, stellar winds, and kinetic theory applications in astrophysical plasma; he also worked on analysis of ultraviolet spectra of hot stars and related modelling methods.[1][2][3] Sirp and the Estonian Academy yearbook highlight his 1978 work at NASA’s Goddard Space Flight Center using the International Ultraviolet Explorer satellite telescope to study ultraviolet stellar spectra, with subsequent long-term analysis of the recorded data in Estonia.[4][6]
ERR’s obituary notes that he held international scientific-organization roles, including work connected to the International Astronomical Union and leadership roles in Soviet-era stellar-atmosphere working groups and astronomical societies.[5]
Recognition and legacy
Sapar received the Order of the White Star, 4th Class, by presidential decision published in the official gazette Riigi Teataja (2006).[7] He was also awarded the Estonian Academy of Sciences Medal (1986).[8] A minor planet was named in his honour; this is described in Estonian popular-history coverage and in Academy yearbook material.[9][6]
Selected works
- Sapar, A. (1977). “Evidence for the fundamental role of Planck units in cosmology.” Publ. Tartu Astrofiz. Obs. 45.[10]
- Sapar, A.; Sapar, L.; Poolamäe, R. (2003). “Analytical solutions for saturated P Cygni type profiles II: General case.” Astrophysics and Space Science 286:333.[11]
- Sapar, A. (2000). “Modelling and diagnostics of smooth winds.” In: Thermal and Ionization Aspects of Flows from Hot Stars: Observations and Theory (ASP Conf. Ser. 204).[12]
See also
References
- ^ a b c "NIMI Arved-Ervin Sapar – TEADUSALA Astrofüüsika" (PDF). Estonian Academy of Sciences. Retrieved 13 February 2026.
- ^ a b c d e f "Akadeemik Arved-Ervin Sapar 7.02.1933–1.12.2021" (PDF). Estonian Academy of Sciences. Retrieved 13 February 2026.
- ^ a b c d e "Suri astrofüüsik Arved-Ervin Sapar". University of Tartu. Retrieved 13 February 2026.
- ^ a b "Arved-Ervin Sapar 7. II 1933 – 1. XII 2021". Sirp. 10 December 2021. Retrieved 13 February 2026.
- ^ a b "Suri akadeemik Arved-Ervin Sapar". Novaator (ERR). 2 December 2021. Retrieved 13 February 2026.
- ^ a b "Eesti Teaduste Akadeemia aastaraamat 2021: Faktid ja arvud (veebi)" (PDF). Estonian Academy of Sciences. 30 April 2022. Retrieved 13 February 2026.
- ^ "994368 – Riiklike autasude andmine (Riigi Teataja)". Riigi Teataja. 6 February 2006. Retrieved 13 February 2026.
- ^ "EESTI TEADUSTE AKADEEMIA MEDAL (saajad)" (PDF). Estonian Academy of Sciences. Retrieved 13 February 2026.
- ^ "Väikeplaneet sai nime Paatna külapoisi järgi «Sapar»". Imeline Ajalugu. Retrieved 13 February 2026.
- ^ "Evidence for the fundamental role of Planck units in cosmology". ETDE/OSTI. Retrieved 13 February 2026.
- ^ Sapar, A.; Sapar, L.; Poolamäe, R. (2003). "Analytical solutions for saturated P cygni type profiles II: General case". Astrophysics and Space Science. 286 (3): 333. Bibcode:2003Ap&SS.286..333S. doi:10.1023/A:1026374800760. Retrieved 13 February 2026.
- ^ Sapar, A. (2000). "Modelling and Diagnostics of Smooth Winds (ASP Conf. Ser. 204)". Thermal and Ionization Aspects of Flows from Hot Stars. 204: 123. Bibcode:2000ASPC..204..123S. Retrieved 13 February 2026.