We said goodbye to Andrei Sakharov on December 14th, 1989, 30 years ago. He lived just long enough to witness the total collapse of the evil regime he had spent much of his life in opposition to.

As a PhD physicist, his primary interest was initially in cosmic rays, but he was assigned to the postwar team that developed the first Soviet atomic bomb. They were able to produce one rapidly because Soviet spies had stolen the technology from the US Manhattan Project. Sakharov researched a possible way of making thermonuclear weapons in a way that was totally original, however, and produced a device radically different from the US Teller-Ulam design. Although the US exploded the first H-bomb, Sakharov's design for the Soviet Union was in many ways more practical, and gave them a brief lead in thermonuclear technology.

His work made Sakharov a leading figure, a position he used to campaign for civil liberties and human rights, to the increasing concern of the authorities. He was also concerned by the implications of his scientific work, and opposed both nuclear proliferation and atmospheric testing. He was involved in the 1963 Partial Test Ban Treaty.

Sakharov broke with tradition by publicly opposing the election of Nikolai Nuzhdin to the Soviet Academy of Sciences, citing his responsibility for "the defamation, firing, arrest, even death, of many genuine scientists." When he succeeded in preventing the election, the KGB began to compile a dossier on Sakharov.

From 1968, he emerged as the leading dissident figure, publishing calls for civil liberties and staging vigils outside closed courtrooms. He made public appeals on behalf of over 200 prisoners he thought were unjustly detained. He was in 1970 a founder member of the USSR's Committee on Human Rights. With others he wrote petitions and established contacts with international groups campaigning for human rights.

He came under increasing pressure and, when awarded the 1975 Nobel Peace Prize, was not allowed to leave the country to collect it. His wife did, though, on his behalf. Sakharov wrote publicly that the state he had once thought of as a breakthrough to a better future for mankind, was now corrupted.

"Yet our state is similar to a cancer cell – with its messianism and expansionism, its totalitarian suppression of dissent, the authoritarian structure of power, with a total absence of public control in the most important decisions in domestic and foreign policy, a closed society that does not inform its citizens of anything substantial, closed to the outside world, without freedom of travel or the exchange of information."

After he opposed the Soviet war in Afghanistan, he was exiled to Gorky, off-limits to foreigners, in 1980, and was held in internal exile until 1986. When his wife was arrested, he went in hunger strike to demand her release, and to allow her to travel abroad for heart surgery. He was detained in hospital and force-fed. The Politburo, under international pressure now, allowed her to go for surgery in the US, but sentenced her to Gorky on her return. Finally, in 1986, Gorbachev told them they could return to Moscow.

There are many Sakharov prizes now to recognize those who campaign for human rights, including the European Sakharov Prize for Freedom of Thought. There are also streets named after him and statues to honour his contribution. He was a brave man, enduring innumerable seizures, searches and detentions, but ultimately he won. He shamed his country, and in doing so, helped bring about the demise of one of the most corrupt and poisonous ideologies that ever held sway.