Kardashev/ community

03The scientist

Nikolai Kardashev

A Soviet and Russian radio astronomer who spent his career building sharper ways to listen to the sky, and who asked in 1964 how much power a civilization would need to be heard across it.

Николай Семёнович Кардашёв
25 April 1932 – 3 August 2019
Radio astronomer · Moscow

3.1Life

A radio astronomer first.

Nikolai Semyonovich Kardashev was born in Moscow on 25 April 1932.

He graduated from the Department of Astronomy of Moscow State University in 1955 and became a student of Iosif Shklovsky at the university’s Sternberg Astronomical Institute. He earned the higher Soviet doctorate, Doctor of Sciences, in 1965.

From 1967 he worked at the Space Research Institute (IKI) of the USSR Academy of Sciences. In 1990 he founded the Astro Space Center of the Lebedev Physical Institute, which he led until his death in Moscow on 3 August 2019.

3.2Timeline

Selected dates

  1. 1932
    Born in Moscow25 April 1932.
  2. 1955
    Graduates from Moscow State UniversityDepartment of Astronomy. He went on to postgraduate work at the university’s Sternberg Astronomical Institute under Iosif Shklovsky.
  3. 1959
    Predicts radio recombination linesHe showed that transitions between highly excited levels of hydrogen should produce observable lines in the radio spectrum. Soviet radio astronomers first detected such lines in 1964.
  4. 1964
    The paper behind the scaleTransmission of Information by Extraterrestrial Civilizations, presented in May at the First All-Union Conference on Extraterrestrial Civilizations at Byurakan, Armenia. The same year he published work on magnetic fields of collapsing stars, later linked to the pulsar idea.
  5. 1965
    Very-long-baseline interferometryWith Leonid Matveenko and Gennady Sholomitsky he published the idea of combining recordings from widely separated radio telescopes, each with its own clock, into one interferometer. The same year he became a Doctor of Sciences.
  6. 1967
    Space Research Institute (IKI)He moved to IKI of the USSR Academy of Sciences, where he worked until 1990.
  7. 1976
    Corresponding memberElected a corresponding member of the USSR Academy of Sciences.
  8. 1988
    USSR State PrizeShared for the discovery of radio recombination lines. He had also received the prize in 1980.
  9. 1990
    Astro Space CenterFounded the Astro Space Center of the Lebedev Physical Institute in Moscow and led it for the rest of his life.
  10. 1994
    AcademicianElected a full member of the Russian Academy of Sciences.
  11. 1997
    IAU Vice-PresidentVice-President of the International Astronomical Union, 1997–2003.
  12. 2011
    RadioAstron launchesOn 18 July the Spektr-R spacecraft carried RadioAstron’s 10-metre radio telescope into a high orbit. Linked with ground telescopes, it formed interferometer baselines of up to about 350,000 km. He had started the project in 1978 and led it.
  13. 2012
    Grote Reber MedalFor innovative contributions to radio astronomy over his lifetime.
  14. 2019
    Died in Moscow3 August 2019, aged 87. RadioAstron had stopped responding in January and was declared complete in May.

3.3Work

Three threads.

RADIO ASTROPHYSICS

Radio recombination lines

In 1959 he predicted that radio recombination lines should be observable. Soviet radio astronomers first detected them in 1964, and the 1988 USSR State Prize he shared recognised their discovery. In 1964 he also published on magnetic fields of collapsing stars, work later linked to the pulsar idea.

SHARPER EYES

VLBI, then space

Very-long-baseline interferometry lets telescopes thousands of kilometres apart work as one, each recording against its own clock. Kardashev was among those who first proposed it. He then led RadioAstron, which put a 10-metre radio telescope in orbit and worked with ground telescopes as one interferometer from 2011 to 2019.

SETI

Who might be transmitting?

His 1964 paper asked what power a civilization would need to send detectable signals across space, and grouped possible senders into the three types now called the Kardashev scale. He suggested two puzzling radio sources, CTA-21 and CTA-102, as candidates. CTA-102 later proved to be a quasar.

3.4Legacy

The scale is the famous part.

Outside astronomy, Kardashev is best known for the scale. Inside it, he is also remembered for radio recombination lines, for early work on VLBI, and for leading RadioAstron, which linked a 10-metre telescope in orbit with radio telescopes on the ground.

He was elected a full member of the Russian Academy of Sciences in 1994 and served as a Vice-President of the International Astronomical Union from 1997 to 2003.

The scale itself was qualitative: three order-of-magnitude bands meant to frame a question about communication, not measurements. The Scale page sets out what he wrote and how others changed it.

Policy

This page sticks to published facts. It does not attribute quotes, opinions or views on present-day projects to Kardashev, who died in 2019.

3.5Sources

Sources and further reading

  1. L. I. Gurvits, Y. Y. Kovalev and P. G. Edwards, obituary of Nikolai Kardashev, Physics Today (2019). physicstoday.aip.org
  2. Astro Space Center of the Lebedev Physical Institute, memorial site. kardashev.asc.rssi.ru
  3. N. S. Kardashev, Transmission of Information by Extraterrestrial Civilizations, Soviet Astronomy 8, 217 (1964). NASA ADS
  4. N. S. Kardashev, L. I. Matveenko and G. B. Sholomitsky, Large base-line radio interferometers, Izvestiya VUZov Radiofizika 8, 651 (1965).
  5. N. S. Kardashev et al., RadioAstron: a telescope with a size of 300 000 km, Astronomy Reports 57, 153 (2013). arXiv:1303.5013
  6. International Astronomical Union, individual member page. iau.org
  7. Grote Reber Medal, list of recipients. atnf.csiro.au
  8. L. M. Gindilis and L. I. Gurvits, history of SETI in the USSR and Russia, Acta Astronautica (2019). arXiv:1905.03225