Jaan Einasto (born 23 February 1929) is an

Estonia Estonia, formally the Republic of Estonia, is a country by the Baltic Sea in Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to the west by the sea across from Sweden, to the south by Latvia, a ...

n astrophysicist and one of the discoverers of the large-scale structure of the

Universe The universe is all of space and time and their contents, including planets, stars, galaxies, and all other forms of matter and energy. The Big Bang theory is the prevailing cosmological description of the development of the universe. ...

. Born Jaan Eisenschmidt in Tartu, the name "Einasto" is an anagram of "Estonia" (it was chosen by his patriotic father in the 1930s to replace the family's German name). He attended the

University of Tartu The University of Tartu (UT; et, Tartu Ülikool; la, Universitas Tartuensis) is a university in the city of Tartu in Estonia. It is the national university of Estonia. It is the only classical university in the country, and also its biggest ...

, where he received the

Ph.D. A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is ...

equivalent in 1955 and a senior research doctorate in 1972. From 1952, he has worked as a scientist at the Tartu Observatory (1977–1998) Head of the Department of

Cosmology Cosmology () is a branch of physics and metaphysics dealing with the nature of the universe. The term ''cosmology'' was first used in English in 1656 in Thomas Blount's ''Glossographia'', and in 1731 taken up in Latin by German philosopher ...

; from 1992–1995, he was Professor of Cosmology at the University of Tartu. For a long time, he was Head of the Division of

Astronomy Astronomy () is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, g ...

and

Physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which r ...

of the

Estonian Academy of Sciences Founded in 1938, the Estonian Academy of Sciences ( et, Eesti Teaduste Akadeemia) is Estonia's national academy of science in Tallinn. As with other national academies, it is an independent group of well-known scientists whose stated aim is to ...

Tallinn Tallinn () is the most populous and capital city of Estonia. Situated on a bay in north Estonia, on the shore of the Gulf of Finland of the Baltic Sea, Tallinn has a population of 437,811 (as of 2022) and administratively lies in the Harju '' ...

. Einasto is a member of the

Academia Europaea The Academia Europaea is a pan-European Academy of Humanities, Letters, Law, and Sciences. The Academia was founded in 1988 as a functioning Europe-wide Academy that encompasses all fields of scholarly inquiry. It acts as co-ordinator of Europea ...

, the

European Astronomical Society The European Astronomical Society (EAS) is a learned society, founded under the Swiss Civil Code in 1990, as an association to contribute and promote the advancement of astronomy in Europe, and to deal with astronomical matters at a European lev ...

and the

Royal Astronomical Society (Whatever shines should be observed) , predecessor = , successor = , formation = , founder = , extinction = , merger = , merged = , type = NG ...

; he has received three Estonian National Science Awards. *1947 Tartu Secondary School No. 1 *1952 University of Tartu *1955 Cand.Sc. in physics and mathematics *1972 D.Sc. in physics and mathematics *1992 Professor Since 1991 he is member of Academia Europaea. Since 1994 he is member of the Royal British Society of Astronomy. The asteroid 11577 Einasto, discovered in 1994, is named in his honour. In 1974, in a seminal work with Kaasik and Saar at the

Tartu Observatory The Tartu Observatory ( et, Tartu Observatoorium) is the largest astronomical observatory in Estonia. On 1 January 2018, Tartu Observatory was joined again to the University of Tartu, and the observatory is now an institute of the university. I ...

, Einasto argued that "it is necessary to adopt an alternative hypothesis: that the clusters of galaxies are stabilised by hidden matter." This was a key paper in recognizing that a hidden matter, i.e.,

dark matter Dark matter is a hypothetical form of matter thought to account for approximately 85% of the matter in the universe. Dark matter is called "dark" because it does not appear to interact with the electromagnetic field, which means it does not a ...

, could explain observational anomalies in astronomy. Einasto showed in 1977 at a Symposium in Tallinn (Estonia) that the universe has a cell structure, in which the observed matter surrounds huge empty voids.

References

External links

Jaan Einasto
page at the Tõravere Observatory 1929 births Cosmologists Living people Estonian astrophysicists Estonian astronomers 20th-century Estonian physicists Members of Academia Europaea Members of the Estonian Academy of Sciences Recipients of the Order of the National Coat of Arms, 2nd Class University of Tartu alumni Hugo Treffner Gymnasium alumni People from Tartu {{Europe-astronomer-stub

See also

References

External links