A strange discovery of a system of six planets in perfect harmony

Led study University of Chicago Astronomer Raphael Locke might tell us how planets form.

Scientists have discovered a rare sight in a nearby star system: six planets orbiting their central star in a rhythmic rhythm. The planets move in an orbital waltz that repeats itself so precisely that it can easily be set to music.

In a rare case of “synchronized” gravitational harmony, the system could provide profound insight into the planet’s formation and evolution.

The analysis, conducted by University of Chicago scientist Raphael Locke, was published on November 29 in the journal Science nature.

“This discovery will become a reference system for studying how sub-Neptunian planets, the most common type of planets outside the solar system, form and evolve, what they are made of, and whether they have the right conditions to support their existence from liquid water on their surfaces,” Lokey said.

Artist’s illustration of the six newly discovered planets orbiting their star in resonance. Credit: Roger Thibaut (NCCR PlanetS)

Cosmic Ballet at Coma Berenice

The six planets orbit a star known as HD110067, which is located about 100 light-years away in the northern constellation of Berenice.

In 2020, NASATransiting Exoplanet Survey Satellite (he-goat) He discovered dips in the star’s brightness that indicate planets passing in front of the star’s surface. Combining data from both TESS and European Space AgencyIn describing the exoplanet satellite Khovs, a team of researchers analyzed the data and discovered the first-of-its-kind configuration.

While multi-planet systems are common in our galaxy, those in a tight gravitational configuration known as a “resonance” are observed by astronomers much less frequently.

In this case, the planet closest to the star makes three orbits for every two of the next planet — called a 3/2 resonance — a pattern repeated among the four closest planets. Among the exoplanets, a pattern of four orbits for every three of the following planets (4/3 resonance) is repeated twice.

“It shows us the original formation of an untouched planetary system.”

— Raphael Locke

These resonant orbits are rock-solid: The planets have likely been performing the same rhythmic dance since the system formed billions of years ago, scientists said.

This animation shows six “sub-“NeptuneThe exoplanets move in rhythmic orbits around their star – with a musical note as each planet passes a line drawn through the system. The line is where planets cross in front of (“transit”) their star from Earth’s perspective. In these rhythms, known as resonances, the innermost planet makes three orbits for every two orbits of the next planet. Among the exoplanets, a pattern of four orbits for every three of the following planets is repeated twice. Credit: Dr. Hugh Osborne, University of Bern

Rare in the galaxy

Finding orbital resonance systems is very important because they tell astronomers about the formation of a planetary system and its subsequent evolution. Circumstellar planets tend to form in resonance, but can easily become disturbed. For example, a very massive planet, a nearby collision with a passing star, or a giant impact event could upset the delicate balance. As a result, many multiplanetary systems known to astronomers are not in resonance but appear close enough that they could have resonance at once. However, multi-planet systems that maintain their resonance are rare.

“We think that only about 1% of all systems remain in resonance, and a smaller number show a series of planets in such a configuration,” Luckey said. That’s why HD110067 is special and calls for further study: “It shows us the original formation of an untouched planetary system.”

More precise measurements of the masses and orbits of these planets will be needed to sharpen the picture of how the system formed.

To learn more about this discovery, see Unraveling the Mystery of the Resonance of the Six Planets.

Reference: “A resonant sextet of sub-Neptunian planets crossing the bright star HD 110067” by R. Luque, HP Osborn, A. Leleu, E. Pallé, A. Bonfanti, O. Barragán, T. G. Wilson, C. Broeg, A. Collier-Cameron , Mother. Lindell, B. F. L. Maxted, Y. Alibert, D. Gandolfi, J.-P. Delisle, M.J. Houghton, J.A. Egger, G. Nowak, M. Lafarga, D. Rapetti, J.D. Tuecken, J.C. Morales, I. Carlio, J. Aurel Mikel, V. Adebekian, R. Alonso, A. Al-Qasim, P.J. Amado, Dr. Anderson, J. Anglada-Escudi, T. Pandey, T. Barkzi, Dr. Parrado Navasquez, SCC Barros, W. Bomjohan, Dr. Bayliss, J.L. Bean, M. Beck, T. Beck, W. Benz, N. Bellot, Sz. Csizmadia, P.E. Cubillos, F. Dai, M.B. Davies, H.J. Deeg, M. Deleuil, A. Deline, L. Delrez, O.D.S. Demangeon, B.-O. Demory, D. Ehrenreich, A. Erickson, E. Esparza Borges, b. Falk, A. Fortier, L. Fossati, M. Friedlund, A. Fukui, J. Garcia-Mejia, S. Gill, M. Gillon, E. Goffo, Y. Gómez Maqueo Chew, M. Güdel, EW Guenther, MN Günther, AP Hatzes, Ch. Hilling, K. M. Hess, S. B. Howell, S. Hoyer, K. Ikuta, K. G. Isaac, J. M. Jenkins, T. Kagitani, L. L. Case, T. Kodama, J. Kurth, K. W. F. Lam, J. Laskar, D. W. Latham, A. Lecavilliers des Etangs, J. P. D. Leon, J. H. Livingston, D. Magrin, R. A. Matson, E. C. Matthews, C. Mordasini, M. Mori, M. Moyano, M. Munari, F. Murgas, N. Narita, V. Nascimbini, G. Olofsson, H. L. M. Osborne, R. Ottensamer, I. Pagano, H. Parviainen, J. Peter, J. Piotto, D. Polacco, D. Queloz, S.N. Quinn, A. Kerenbach, R. Ragazzoni, N. Rando, F. Ratti, H. Rauer, S. Redfield, I. Ribas, GR Ricker, A. Rudat, L. Sabin, S. Salmon, N. C. Santos, G. Scandariato, N. Schanche, J. E. Schlieder, S. Seager, D. Ségransan ,A. Shporer, A.E. Simon, A.M.S. Smith, S.G. Sousa, M. Stalport, Gy. M. Szabó, N. Thomas, A. Tuson, S. Udry, A. M. Vanderburg, V. Van Eylen, V. Van Grootel, J. Venturini, I. Walter, N. A. Walton, N. Watanabe, J. N. Winn and T. Zingales , November 29, 2023, nature.
doi: 10.1038/s41586-023-06692-3

Professor Jacob Bean from the University of Chicago was also a co-author of this paper.