Jean-Marc Bonnet-Bidaud

Last updated
Jean-Marc Bonnet-Bidaud
Jean-Marc Bonnet-Bidaud en 2012.jpg
Born1950
Nationality French
Scientific career
FieldsHigh-energy astrophysics, highly condensed stars in the galaxy
Institutions Atomic Energy and Alternative Energies Commission (CEA)
Website bonnetbidaud.free.fr

Jean-Marc Bonnet-Bidaud (born 1950) is a French astrophysicist at the Atomic Energy and Alternative Energies Commission (CEA). He is a specialist in high-energy astrophysics and in the study of highly condensed stars in the galaxy (white dwarfs, neutron stars and black holes). He is also active in the field of the history of astronomy and in charge of the public outreach for astronomy at CEA.

Contents

Scientific work

Among his highest citation scientific papers are the discovery and collaborative study of an atypical supernova observed in 2006, [1] [2] [3] a scientific review on the enigmatic X-ray source Cygnus X-3 and its reported very high energy emission [4] [5] and the discovery of abnormal CNO abundances among accreting magnetic white dwarfs. [6] [7] [8]

From 2009, Jean-Marc Bonnet-Bidaud is involved in the StarAcc project (initially POLAR project) [9] which aims to reproduce in the laboratory physical conditions similar to those existing on the surface of magnetic white dwarfs thanks to the use of lasers of power. The POLAR project reached an essential milestone in 2016 by demonstrating for the first time the possibility of reproducing in the laboratory an accretion structure (accretion shock and radiative zone) in agreement with numerical predictions and astrophysical observations [10] [11] [12]

This result opens the way to the use of very energetic lasers, such as the NIF (National Ignition Facility-USA) or the LMJ (Laser Megajoule-France), to achieve radiative regimes strictly homothetic to the astrophysical situation. [13] Ultimately, these experiments should make it possible to reliably produce miniature models in the laboratory that are almost analogous to real astrophysical conditions. [14]

History of science

History of cosmology

With the philosopher of science Thomas Lepeltier, Jean-Marc Bonnet-Bidaud co-directed the publication in 2012 of the collective work Un autre cosmos ?. [15] The central idea of the book is to encourage researchers to look into alternative cosmological models to that of the Big Bang. [16]

In 2021, Jean-Marc Bonnet-Bidaud and Thomas Lepeltier published the work Big Bang - Histoire critique d'une idée, [17] in which the evolution of the idea of an expanding universe evolving at from a hot phase, at the basis of the current cosmology of the Big Bang is discussed. The authors show how this basic hypothesis evolved in several stages to arrive at the current model known as LCDM (Lamba-Cold-Dark-Matter) in which 95% of the content of the universe remains unknown. A critical analysis is provided of the assumptions underlying this model, highlighting the current difficulties. [18] [19]

Chinese astronomy

Bonnet-Bidaud is the author of the first scientific study of the oldest known stellar map, the Dunhuang Star Chart, also known as the S.3326 manuscript, a document found in China along the Silk road and now kept at the British Library in London, England. The study concludes to a now revised datation at +650-685, making the chart contemporary of the early Tang dynasty and most probably produced by the famous Chinese astronomer Li Chunfeng. [20] [21] [22] [23] [24] [25]

He has produced in 2017 the book 4000 ans d'astronomie chinoise , that gives an overview of the astronomical discoveries made in China over centuries. The book has been translated in Chinese in 2020 : 书名:4000年中国天文史. [26]

Bibliography

Books

Films

Related Research Articles

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Physical cosmology is a branch of cosmology concerned with the study of cosmological models. A cosmological model, or simply cosmology, provides a description of the largest-scale structures and dynamics of the universe and allows study of fundamental questions about its origin, structure, evolution, and ultimate fate. Cosmology as a science originated with the Copernican principle, which implies that celestial bodies obey identical physical laws to those on Earth, and Newtonian mechanics, which first allowed those physical laws to be understood.

<span class="mw-page-title-main">Olbers's paradox</span> Argument in astrophysics against the theory of an unchanging universe

Olbers's paradox, also known as the dark night paradox, is an argument in astrophysics and physical cosmology that says that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. In the hypothetical case that the universe is static, homogeneous at a large scale, and populated by an infinite number of stars, any line of sight from Earth must end at the surface of a star and hence the night sky should be completely illuminated and very bright. This contradicts the observed darkness and non-uniformity of the night sky.

<span class="mw-page-title-main">Sirius</span> Brightest star in the night sky, in the constellation Canis Major

Sirius is the brightest star in the night sky. Its name is derived from the Greek word Σείριος, meaning lit. 'glowing' or 'scorching'. The star is designated α Canis Majoris, Latinized to Alpha Canis Majoris, and abbreviated α CMa or Alpha CMa. With a visual apparent magnitude of −1.46, Sirius is almost twice as bright as Canopus, the next brightest star. Sirius is a binary star consisting of a main-sequence star of spectral type A0 or A1, termed Sirius A, and a faint white dwarf companion of spectral type DA2, termed Sirius B. The distance between the two varies between 8.2 and 31.5 astronomical units as they orbit every 50 years.

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<span class="mw-page-title-main">Astronomy</span> Scientific study of celestial objects

Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest include planets, moons, stars, nebulae, galaxies, meteoroids, asteroids, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates beyond Earth's atmosphere. Cosmology is a branch of astronomy that studies the universe as a whole.

<span class="mw-page-title-main">Supermassive black hole</span> Largest type of black hole

A supermassive black hole is the largest type of black hole, with its mass being on the order of hundreds of thousands, or millions to billions, of times the mass of the Sun (M). Black holes are a class of astronomical objects that have undergone gravitational collapse, leaving behind spheroidal regions of space from which nothing can escape, including light. Observational evidence indicates that almost every large galaxy has a supermassive black hole at its center. For example, the Milky Way galaxy has a supermassive black hole at its center, corresponding to the radio source Sagittarius A*. Accretion of interstellar gas onto supermassive black holes is the process responsible for powering active galactic nuclei (AGNs) and quasars.

<span class="mw-page-title-main">Nommo</span> Primordial ancestral spirits in Dogon religion and cosmogony

The Nommo or Nummo are primordial ancestral spirits in Dogon religion and cosmogony venerated by the Dogon people of Mali. The word Nommos is derived from a Dogon word meaning "to make one drink." Nommos are usually described as amphibious, hermaphroditic, fish-like creatures. Folk art depictions of Nommos show creatures with humanoid upper torsos, legs/feet, and a fish-like lower torso and tail. Nommos are also referred to as "Masters of the Water", "the Monitors", and "the Teachers". Nommo can be a proper name of an individual or can refer to the group of spirits as a whole. For purposes of this article, "Nommo" refers to a specific individual and "Nommos" is used to reference the group of beings.

<span class="mw-page-title-main">Canopus</span> Star in the constellation of Carina

Canopus is the brightest star in the southern constellation of Carina and the second-brightest star in the night sky. It is also designated α Carinae, which is romanized (transliterated) to Alpha Carinae. With a visual apparent magnitude of −0.74, it is outshone only by Sirius.

<span class="mw-page-title-main">Beta Canis Majoris</span> Star in the constellation Canis Major

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<span class="mw-page-title-main">Centaurus X-3</span> Binary star with an X-ray pulsar in the constellation Centaurus

Centaurus X-3 is an X-ray pulsar with a period of 4.84 seconds. It was the first X-ray pulsar to be discovered, and the third X-ray source to be discovered in the constellation Centaurus. The system consists of a neutron star orbiting a massive, O-type supergiant star dubbed Krzeminski's star after its discoverer, Wojciech Krzemiński. Matter is being accreted from the star onto the neutron star, resulting in X-ray emission.

<span class="mw-page-title-main">Accretion (astrophysics)</span> Accumulation of particles into a massive object by gravitationally attracting more matter

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<span class="mw-page-title-main">Cosmology</span> Scientific study of the origin, evolution, and eventual fate of the universe

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<span class="mw-page-title-main">Star chart</span> Map of the night sky

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<span class="mw-page-title-main">Dunhuang Star Chart</span> Star atlas from ancient Chinese astronomy, dated to the Tang dynasty (618–907)

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<span class="mw-page-title-main">Nathalie Palanque-Delabrouille</span> French cosmologist

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References

  1. Pastorello, A.; et al. (2007). "A giant outburst two years before the core-collapse of a massive star". Nature. 447 (7146): 829–32. arXiv: astro-ph/0703663 . Bibcode:2007Natur.447..829P. doi:10.1038/nature05825. PMID   17568740. S2CID   4409319.
  2. "A supernova that explodes twice" on YouTube, 19 June 2007.
  3. "Warning shot for a cataclysm" , CEA scientific news, Commissariat à l'énergie atomique et aux énergies alternatives , 14 June 2007.
  4. M. van der Klis; J.M. Bonnet-Bidaud (1989). "The X-ray ephemeris of Cygnus X-3". Astronomy and Astrophysics . 214: 203. Bibcode:1989A&A...214..203V.
  5. J.M. Bonnet-Bidaud; G. Chardin (1988). "Cygnus X-3, a critical review". Physics Reports . 170 (6): 325–404. Bibcode:1988PhR...170..325B. doi:10.1016/0370-1573(88)90083-X.
  6. J.M. Bonnet-Bidaud; M. Mouchet (1987). "The anomalous ultraviolet spectrum of the AM HER star H 0538 + 608". Astronomy and Astrophysics . 188: 89. Bibcode:1987A&A...188...89B.
  7. M. Mouchet; et al. (2003). "The surprising Far-UV spectrum of the polar BY Camelopardalis". Astronomy and Astrophysics . 401 (3): 1071–1076. arXiv: astro-ph/0302312 . Bibcode:2003A&A...401.1071M. doi:10.1051/0004-6361:20030176. S2CID   17177011.
  8. "Overabundance of nitrogen onto a magnetic white dwarf" Archived 2013-03-07 at the Wayback Machine , Paris-Meudon Observatory scientific news Paris Observatory , Mars 2003.
  9. « Projet StarAcc (Stellar Objects Accretion column) », irfu.cea.fr.
  10. Cross, J.E.; et al. (2016). "Laboratory analogue of a supersonic accretion column in a binary star system". Nature Communications . 7: id. 11899. Bibcode:2016NatCo...711899C. doi: 10.1038/ncomms11899 . PMC   4910020 .
  11. Lehoucq, R. (12 September 2016). "Une étoile en laboratoire". Le Monde Sciences.
  12.  Siphonner » une étoile : reconstitution par laser" , Communiqué de presse CEA, Commissariat à l'énergie atomique et aux énergies alternatives , 15 June 2016
  13. Michel Koenig; Emeric Falize (December 2015). "Recréer l'univers". La Recherche . 506: 34–39.
  14. "L'Univers en laboratoire: les Naines blanches magnétiques", 13 September 2017 on YouTube
  15. Un autre cosmos ?, vuibert.fr.
  16. « Le modèle du Big Bang est fragile, un entretien avec Jean-Marc Bonnet-Bidaud », par Pierre Barthélémy dans Le Monde.fr , 14 mai 2012.
  17. Big Bang - Histoire critique d'une idée (in French). Paris: Gallimard. 2021. ISBN   978-2072586491.
  18. "Big Bang, ça tangue !" France Culture, La Méthode scientifique par Nicolas Martin (journalist) 7 April 2022.
  19. "Le modèle du Big Bang pourrait ne pas être bien établi" par Jacques-Olivier Baruch dans Sciences et Avenir , 9 April 2022.
  20. J.M. Bonnet-Bidaud; F. Praderie; S. Whitfield (2009). "The Dunhuang Chinese sky: a comprehensive study of the oldest known star atlas". Journal of Astronomical History and Heritage . 12 (1): 39–59. arXiv: 0906.3034 . Bibcode:2009JAHH...12...39B. doi:10.3724/SP.J.1440-2807.2009.01.04. S2CID   55911862.
  21. Qiu, Jane (2009). "Charting the heavens from China". Nature . 459 (7248): 778–779. Bibcode:2009Natur.459..778Q. doi: 10.1038/459778a .
  22. "Dunhuang star atlas" , APOD Astronomy Picture of the Day , 19 June 2009.
  23. Mathieu Grousson (2010). "The oldest celestial atlas". CNRS International Magazine. 18: 14.
  24. "Charting the heavens from a Chinese perspective" , Irish Times.com, Irish Times , 9 Septembre 2011.
  25. "Star maps and astronomy in ancient China" in "The Silk Road: Trade, Travel, War and Faith", The British Library, ed. Susan Whitfield, 2004.
  26. 书名:4000年中国天文史 (in Chinese). Beijing: CITIC. 2021. ISBN   978-7521713527.