Ernst Julius Öpik was an Estonian astronomer of international standing whose long career included, after exile from his homeland, which he never forgot, four decades based at the world-famous Armagh Observatory. 

Öpik was born in Kunda, a village in the parish of Lääne-Viru, in the Governorate of Estonia, then a part of the Russian Empire, one of the ten children of Karl Heinrich Öpik, a customs officer, and Leontine Johanna Freiwald. At his birth the Old Style system was still in use, hence the double date of 10 October is sometimes given. In 1900 Ernst left Kunda for Tallinn, principal city of Estonia where he attended the venerable Gustav Adolfi Gümnaasium, or Gustav Adolf Gymnasium, founded as the Reval Gymnasium in 1631 by King Gustav II Adolf of Sweden, though the original buildings dated back to the 14th century. The school thus always reflected the political situation in Estonia, which at various times was occupied by Sweden, Denmark and Germany, then Russia, when it was renamed (again), becoming the Nikolai Gymnasium. (As of 2022 the school’s official name, in Estonian, is Gustav Adolfi Gümnaasium, flourishing with over 1300 students and proud to be one of the oldest institutions of its kind in the world.) 

Öpik graduated from the school in 1911 with the gold medal. In the autumn of 1912 he began his studies at the University of Moscow. He chose the University of Moscow rather than the University of Tartu because in Moscow he could earn some money giving lessons but it was still a great struggle and he had to run up debts living in the Moscow Society of Estonia dormitory which he settled when he had the chance to give more lessons. Despite these difficulties, between 1912 and 1916 he produced 18 articles, showing a rapid development from an amateur level at the beginning to a top world-class researcher by the end of the four years. He graduated with an astronomy degree in 1916 and continued to work to qualify as a university professor.

The Russian Revolution of 1917 saw the country enter political chaos, with coup attempts and a collapsing economy with food shortages. Moscow remained relatively quiet for much of 1917 but, after the Bolsheviks seized power in St Petersburg in October, fighting began in Moscow. By 3 November the Bolsheviks were in control of the city. Öpik was totally opposed to the Bolsheviks so he joined the White Army, travelling to Yaroslavl where the Red Army was stationed. Öpik had a mysterious girlfriend in Yaroslavl which proved useful when he was captured by the Bolsheviks and sentenced to death. He claimed he had been using false identity papers so he could visit his married lover in Yaroslavl. He must have been convincing for he was released and able to return to astronomy in Moscow.

At the beginning of 1919, when Bolshevik rule was firmly established in most of Russia, with some fighting still continuing on the fringes, the new rulers decided to found a university in Tashkent . Over 100 professors and other teaching staff with their families volunteered to leave starving Moscow and to start a new life in the food-rich but otherwise risky Asiatic surroundings. As the only astronomer in the group, Öpik I was to be Chairman of Astronomy and put new life into Tashkent Observatory. A former military geodetic observatory, it had somehow fallen into disarray during the Revolution, and it was now to be made an integral part of the new Turkestan University. Rail communications in Russia were at that time in a state of disorganization, and so it was no wonder that the legendary trek of 3000 km from Moscow to Tashkent took 70 days, from the end of January to beginning of April, 1919. After arrival in April, 1919, he served for two years on the faculty of the newly organized Turkestan University Observatory. 

Öpik decided to make efforts to return to Estonia, his beloved native land, which at that time had become an independent country. On 1 December 1921 he was appointed to the University of Tartu where he worked at the Astronomical Observatory. He submitted a thesis on meteor observations to the University of Tartu and was awarded a doctorate in 1923. Öpik was by this time publishing a remarkable number of papers: in 1922 eight of his papers appeared totalling 143 pages; in 1923, eight of his papers appeared totalling 152 pages; in 1924 nine works were published having a total of 479 pages. In 1930 Öpik went to Harvard University in the United States where he spent much time over the following four years as a Visiting Scientist and Lecturer, invited by Harlow Shapley, the Director of the Observatory. 

During his stay in the USA, Öpik created a lot of interest for meteors among the Harvard astronomers and thereby generated the later Harvard meteor programme. Already in 1932, Öpik discussed the influence of stellar perturbations on nearly parabolic ellipses, which 18 years later was to be an important mechanism in Oort's concept of the Comet Cloud surrounding the Sun. It is for this reason that Fred Whipple, who embarked on meteor research because of Öpik's influence, always speaks of the “Öpik-Oort Comet Cloud". 

Öpik returned to the Astronomical Observatory in Tartu in 1934 and there followed a number of agreeable years before World War II. During the war Öpik continued his work barely disturbed by Nazi German occupation, but by 1944 the war was very much running against the occupiers and the counter-occupation by the Soviet Union was a growing likelihood and came to pass in the autumn. Thousands of Estonians fled at short notice, in Öpik’s case with all he could carry in a handcart.

Arriving in Germany, Öpik, went to Hamburg Observatory and was given hospitality until the war ended. After this a Baltic University was set up in Hamburg in March 1946 to provide education for displaced students and Öpik became Professor of Astronomy and the Rector for Estonian students. This University was always going to be a short-term venture so Öpik had to find permanent employment. In fact the University closed in 1949 but Öpik had left in 1948. The astronomers at Harvard learnt of Öpik's predicament and Eric Mervyn Lindsay came to his help. Lindsay was born in Northern Ireland and studied at Queen's University, Belfast. He went to Harvard University to undertake research for his doctorate which he was awarded in 1934. Lindsay had, therefore, been a research student at Harvard at the time Öpik worked there and, in fact, Öpik had been one of the examiners of Lindsay’s PhD thesis. Lindsay had returned to Northern Ireland in 1937 where he was appointed Director of Armagh Observatory. In December 1947 Lindsay offered Öpik the position of Research Associate at Armagh Observatory and he arrived in Northern Ireland to take up the position in June 1948.

Although Öpik continued to work at the Armagh Observatory for the rest of his career, he also made many visits to the University of Maryland in the United States beginning in 1956. A contemporary left this description:

During the semester when he was in residence in Maryland, he usually taught a seminar on a research topic which was currently of interest to him. When I took the seminar (it happened to be about cometary break-up), I found that Dr Öpik had little or no time for teaching material which he considered as already well-established in the field of knowledge. He gave the impression of always wanting to be on the frontiers of knowledge, even in the classroom: anyone who took his seminar was expected, I suppose, to absorb the well-established material elsewhere. 

He remained a lifelong patriot. A newspaper report in November 1962 may show more about Öpik's passionate dislike of Russians than anything else:- 

College Park, Maryland. A world-famous astronomer says he will be pleasantly surprised if the Russian space vehicle now heading towards Mars adds any significant information on space science. Dr Ernest J Öpik, visiting research professor at the University of Maryland, said in an interview Thursday that the "Russians have contributed only five-tenths of one per cent" of the new information on space. “They (the Russians) profess to have sent huge payloads into space 10- 100 times larger than any the United States are capable of sending,” Dr Öpik said. “At the same time, however,”99.5 per cent of all new information on space has come from the United States probes. 

In Northern Ireland, Eric Lindsay initiated the founding of the Irish Astronomical Journal in 1950 edited by Öpik. He remained as Editor until he retired in 1981 at the age of 87. Even after this he continued as an associate editor up until his death in 1985. Other than astronomy, the other passion in Öpik’s life was music. He played the piano to a very high standard, once delivered an after-dinner address in song, and he composed piano pieces which were published. 

Öpik's son was Uno Öpik (1926-2005) who studied at Tartu High School, then left with his parents for Germany in 1944. He studied at the Baltic University 1946-48 after which he moved to Northern Ireland with his parents. He was awarded a PhD from Queen's University, Belfast in 1954. He then taught physics and applied mathematics at several universities with his career mainly being at Queen's in Belfast from 1962 to 1986. Uno Öpik married Liivi Vedo and their elder son was Lembit Öpik (born 1965) who became a successful Liberal Democrat member of the British Parliament from 1997 to 2010. He was also a well-known television personality and presenter of radio and television shows. Lembit was especially well known for his keeping the asteroid question, raised by Ernst many years earlier, before the public. Visitors to the Öpik residence in a leafy suburb near Queen’s University came upon a bohemian home, the front hall decorated by children’s farmyard scenes painted by Uno’s daughter Urve; a pinball machine, and a motorcycle engine. The family’s Estonian patriotism was evinced not just by their speaking in Estonian even in front of non-speakers, but also by a photo of Lembit during a pro-Estonian independence demonstration, complete with Estonian flags, outside the USSR embassy in Stockholm. 

Ernest Öpik received many honours for his outstanding contributions to astronomy. He was elected to the Estonian Academy of Sciences (1938), the Royal Astronomical Society (1949), The Royal Irish Academy (1954), the National Academy of Sciences (United States) (1975), and the American Academy of Arts and Sciences (1977). He received honorary degrees from Queen's University, Belfast (1968) and the University of Sheffield (1977). Among many other prizes and awards he received were the J Lawrence Smith Medal from the National Academy of Sciences (United States) (1960), the FC Leonard Medal of the International Meteoritical Society (1968), a Gold Medal from the American Association for the Advancement of Science (1974), the Gold Medal of the Royal Astronomical Society (1975), the Catherine Wolfe Bruce Gold Medal of the Astronomical Society of the Pacific (1976), and the Louis Jacot Grand Prix, Pensée University, Paris (1978). The asteroid 2099 Öpik is named for him as is the crater Öpik on the Martian moon Phobos. He appears on a 150 franc stamp of the Republic of Mali.

Born:	22 October 1893
Died:	10 September 1985