The DOI matches its Crossref record; 13 of the 13 references it cites were found in a registry or an index.
AN ANCIENT EXTRASOLAR SYSTEM WITH FIVE SUB-EARTH-SIZE PLANETS
Open accessAbstract
The chemical composition of stars hosting small exoplanets (with radii less than four Earth radii) appears to be more diverse than that of gas-giant hosts, which tend to be metal-rich. This implies that small, including Earth-size, planets may have readily formed at earlier epochs in the universe's history when metals were more scarce. We report Kepler spacecraft observations of Kepler-444, a metal-poor Sun-like star from the old population of the Galactic thick disk and the host to a compact system of five transiting planets with sizes between those of Mercury and Venus. We validate this system as a true five-planet system orbiting the target star and provide a detailed characterization of its planetary and orbital parameters based on an analysis of the transit photometry. Kepler-444 is the densest star with detected solar-like oscillations. We use asteroseismology to directly measure a precise age of 11.2 ± 1.0 Gyr for the host star, indicating that Kepler-444 formed when the universe was less than 20% of its current age and making it the oldest known system of terrestrial-size planets. We thus show that Earth-size planets have formed throughout most of the universe's 13.8 billion year history, leaving open the possibility for the existence of ancient life in the Galaxy. The age of Kepler-444 not only suggests that thick-disk stars were among the hosts to the first Galactic planets, but may also help to pinpoint the beginning of the era of planet formation.
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Citations
Cites
A Jupiter-mass companion to a solar-type star
Mayor, M., & Queloz, D. (1995) · Nature · doi:10.1038/378355a0 · Cited by 4,111
Kepler planet-detection mission: Introduction and first results
Borucki, W. J., Koch, D., Basri, G., Batalha, N., Brown, T., Caldwell, D., Caldwell, J., Christensen-Dalsgaard, J., Cochran, W. D., DeVore, E., et al. (2010) · Science · doi:10.1126/science.1185402 · Cited by 4,035
Self-citationHABITABLE ZONES AROUND MAIN-SEQUENCE STARS: NEW ESTIMATES
Kopparapu, R. K., Ramirez, R., Kasting, J. F., Eymet, V., Robinson, T. D., Mahadevan, S., Terrien, R. C., Domagal-Goldman, S., Meadows, V., & Deshpande, R. (2013) · The Astrophysical Journal · doi:10.1088/0004-637x/765/2/131 · Cited by 1,615 · cited 1×
“These orbits are well interior to the inner edge of the system’s habitable zone, which lies 0.47 AU from the parent star if we consider the rather optimistic ‘Recent Venus’ limit of Kopparapu et al. (2013).”
BackgroundInfluentialBorucki, W. J., Koch, D. G., Basri, G., Batalha, N., Brown, T. M., Bryson, S. T., Caldwell, D., Christensen-Dalsgaard, J., Cochran, W. D., DeVore, E., et al. (2011) · The Astrophysical Journal · doi:10.1088/0004-637x/736/1/19 · Cited by 1,042
Self-citationGiant Planet Occurrence in the Stellar Mass-Metallicity Plane
Johnson, J. A., Aller, K. M., Howard, A. W., & Crepp, J. R. (2010) · Publications of the Astronomical Society of the Pacific · doi:10.1086/655775 · Cited by 782
UNDERSTANDING THE MASS-RADIUS RELATION FOR SUB-NEPTUNES: RADIUS AS A PROXY FOR COMPOSITION
Lopez, E. D., & Fortney, J. J. (2014) · The Astrophysical Journal · doi:10.1088/0004-637x/792/1/1 · Cited by 722
THE MASS-RADIUS RELATION FOR 65 EXOPLANETS SMALLER THAN 4 EARTH RADII
Weiss, L. M., & Marcy, G. W. (2014) · The Astrophysical Journal · doi:10.1088/2041-8205/783/1/l6 · Cited by 665
Self-citationAn Earth-mass planet orbiting α Centauri B
Dumusque, X., Pepe, F., Lovis, C., Ségransan, D., Sahlmann, J., Benz, W., Bouchy, F., Mayor, M., Queloz, D., Santos, N., et al. (2012) · Nature · doi:10.1038/nature11572 · Cited by 404 · cited 1×
“Transit and radial velocity surveys have found an increasing number of planets with low mass and/or radius orbiting other suns (Borucki et al. 2011b; Mayor et al. 2011a; Dumusque et al. 2012).”
BackgroundSelf-citationStellar Spin-Orbit Misalignment in a Multiplanet System
Huber, D., Carter, J. A., Barbieri, M., Miglio, A., Deck, K. M., Fabrycky, D. C., Montet, B. T., Buchhave, L. A., Chaplin, W. J., Hekker, S., et al. (2013) · Science · doi:10.1126/science.1242066 · Cited by 315
Self-citationKepler-22b: A 2.4 EARTH-RADIUS PLANET IN THE HABITABLE ZONE OF A SUN-LIKE STAR
Borucki, W. J., Koch, D. G., Batalha, N., Bryson, S. T., Rowe, J., Fressin, F., Torres, G., Caldwell, D. A., Christensen-Dalsgaard, J., Cochran, W. D., et al. (2012) · The Astrophysical Journal · doi:10.1088/0004-637x/745/2/120 · Cited by 241
Self-citation
Cited by
Hot super-Earths stripped by their host stars
Lundkvist, M. S., Kjeldsen, H., Albrecht, S., Davies, G. R., Basu, S., Huber, D., Justesen, A. B., Karoff, C., Silva Aguirre, V., Van Eylen, V., et al. (2016) · Nature Communications · doi:10.1038/ncomms11201 · Cited by 258
Self-citationGuinan, E. F., Engle, S. G., & Durbin, A. (2016) · The Astrophysical Journal · doi:10.3847/0004-637x/821/2/81 · Cited by 77
Metadata
- Authors
- Campante, T. L., Barclay, T., Swift, J. J., Huber, D., Adibekyan, V. Z., Cochran, W., Burke, C. J., Isaacson, H., Quintana, E. V., Davies, G. R., Silva Aguirre, V., Ragozzine, D., Riddle, R., Baranec, C., Basu, S., Chaplin, W. J., Christensen-Dalsgaard, J., Metcalfe, T. S., Bedding, T. R., Handberg, R., Stello, D., Brewer, J. M., Hekker, S., Karoff, C., Kolbl, R., Law, N. M., Lundkvist, M., Miglio, A., Rowe, J. F., Santos, N. C., Van Laerhoven, C., Arentoft, T., Elsworth, Y. P., Fischer, D. A., Kawaler, S. D., Kjeldsen, H., Lund, M. N., Marcy, G. W., Sousa, S. G., Sozzetti, A., & White, T. R.
- Venue
- The Astrophysical Journal
- Publisher
- American Astronomical Society
- Published
- 2015-01-27
- Volume
- 799
- Issue
- 2
- Pages
- 170
- ISSN
- 0004-637X (ISSN-L)
- 1538-4357
- OpenAlex
- W2082378688
- Cited by
- 209
- References
- 13
- FWCI
- 17.75
- Type
- journal article
- Language
- en
- Open access
- bronze
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- Campante, T. L., Barclay, T., Swift, J. J., Huber, D., Adibekyan, V. Z., Cochran, W., Burke, C. J., Isaacson, H., Quintana, E. V., Davies, G. R., Silva Aguirre, V., Ragozzine, D., Riddle, R., Baranec, C., Basu, S., Chaplin, W. J., Christensen-Dalsgaard, J., Metcalfe, T. S., Bedding, T. R., . . . White, T. R. (2015). AN ANCIENT EXTRASOLAR SYSTEM WITH FIVE SUB-EARTH-SIZE PLANETS. The Astrophysical Journal. https://doi.org/10.1088/0004-637x/799/2/170
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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
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