Nature Astronomy最新文献_第2页

Discovery of a second-generation planet candidate accreting onto a white dwarf 发现第二代候选行星吸积到一颗白矮星上

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2026-10-05 DOI: 10.1038/s41550-026-02983-7

Jamie T. Williams, Boris T. Gänsicke, Nicholas C. Stone, Detlev Koester, Benjamin D. R. Davies, Christopher Tong, David J. Wilson, Snehalata Sahu, Andrew Swan, Thomas G. Beatty, Sergio H. Ramírez, Tim Cunningham, Knox S. Long

{"title":"Discovery of a second-generation planet candidate accreting onto a white dwarf","authors":"Jamie T. Williams, Boris T. Gänsicke, Nicholas C. Stone, Detlev Koester, Benjamin D. R. Davies, Christopher Tong, David J. Wilson, Snehalata Sahu, Andrew Swan, Thomas G. Beatty, Sergio H. Ramírez, Tim Cunningham, Knox S. Long","doi":"10.1038/s41550-026-02983-7","DOIUrl":"https://doi.org/10.1038/s41550-026-02983-7","url":null,"abstract":"Many white dwarfs accrete the debris of disrupted planetary bodies, detected in the form of metal enrichment in their atmospheres, dusty or gaseous circumstellar discs, and photometric transits from debris. The composition of accreted debris has been shown to be diverse yet overall closely resembles Solar System bodies. Here we report the discovery of a white dwarf accreting material that is unlike any Solar System object. The atmosphere of HS 0209+0832 is strongly enriched in trans-iron elements including zinc, copper and niobium but depleted in the canonical rock-forming elements silicon and iron. The composition of the accreted object is consistent with a candidate second-generation planet, formed from the stellar material ejected during the giant phase. The key abundance signature that differentiates it from a first-generation planet is the high enrichment of s-process elements. Photospheric helium and the absence of terrestrial rock-forming elements implies that the white dwarf is accreting from the escaped atmosphere of a photo-evaporating giant planet candidate. This is further supported by the detection of a sinusoidal photometric period of 4.399 ± 0.026 days at an amplitude of 0.120% ± 0.018%, which we attribute to thermal emission phase variability from a planetary day–night cycle or a transiting cometary tail of an evaporating gas giant. The discovery of this second-generation planet that is chemically distinct from first-generation material demonstrates that close-in planets around white dwarfs can form after the main sequence.","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"75 1","pages":""},"PeriodicalIF":14.1,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149087858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A white dwarf polluted by its own ashes 一颗被自己的灰烬污染的白矮星

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2026-10-05 DOI: 10.1038/s41550-026-02982-8

Zifan Lin

引用次数: 0

Stable mass transfer from a substellar object onto an M dwarf 稳定的质量转移从一个次恒星物体到一个M矮星

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2026-10-05 DOI: 10.1038/s41550-026-02992-6

Aaron Householder, Kaitlyn Shin, Kevin B. Burdge, Thomas R. Marsh, Saul A. Rappaport, Kareem El-Badry, Joheen Chakraborty, Emma Chickles, Fei Dai, Matthew J. Graham, S. R. Kulkarni, Pablo Rodríguez-Gil, Andrew Vanderburg, Samuel Whitebook

{"title":"Stable mass transfer from a substellar object onto an M dwarf","authors":"Aaron Householder, Kaitlyn Shin, Kevin B. Burdge, Thomas R. Marsh, Saul A. Rappaport, Kareem El-Badry, Joheen Chakraborty, Emma Chickles, Fei Dai, Matthew J. Graham, S. R. Kulkarni, Pablo Rodríguez-Gil, Andrew Vanderburg, Samuel Whitebook","doi":"10.1038/s41550-026-02992-6","DOIUrl":"https://doi.org/10.1038/s41550-026-02992-6","url":null,"abstract":"Substellar objects such as brown dwarfs and planets are generally expected to remain detached from their main-sequence host stars unless orbital decay or stellar expansion brings them into contact, leading to rapid engulfment and destruction. Such a fate is predicted for the Earth and other rocky planets in our Solar System. In certain cases, however, theory also allows for stable long-lived mass transfer from a substellar object onto its main-sequence host, although such accretion has not been observed. Here we report the direct observation of stable mass transfer from a substellar object onto a main-sequence star. In particular, we identify ZTF J0440+2325, an 87-min binary in which a brown dwarf stably transfers mass onto an M dwarf, and present ZTF J1444+4820 (P = 67 min) as a strong candidate low-mass mass-transferring system in a hierarchical triple. These systems demonstrate that the fate of some substellar objects is not rapid engulfment and destruction, but instead gradual consumption for potentially billions of years.","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"6 1","pages":""},"PeriodicalIF":14.1,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149087863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The 15th Asteroids Comets Meteors Conference 第15届小行星、彗星、流星会议

IF 15.2 1区物理与天体物理

Nature Astronomy Pub Date : 2026-10-02 DOI: 10.1038/s41550-026-02995-3

Siegfried Eggl, Agnieszka Kryszczyńska, Dagmara Oszkiewicz, Daniel Hestroffer, Cyrielle Opitom, Regina Rudawska, Agata Rożek

引用次数: 0

First-star imprints in a metal-poor galaxy overdensity near the end of reionization 在一个金属贫乏的星系中，第一颗恒星的印记在再电离结束时密度过高

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2026-09-29 DOI: 10.1038/s41550-026-02993-5

Zihao Li, Koki Kakiichi, Lise Christensen, Zheng Cai, Valentina D’Odorico, Jorryt Matthee, Daichi Kashino, Rongmon Bordoloi, Ruari Mackenzie, Trystyn A. M. Berg, Irene Vanni, Stefania Salvadori, Alessandra Venditti, Shiwu Zhang, Sarah E. I. Bosman, Eduardo Bañados, Frederick B. Davies, Xiaohui Fan, Hyunsung D. Jun, Xiangyu Jin, Mingyu Li, Sofía Rojas-Ruiz, Feige Wang, Jinyi Yang, Siwei Zou, Huanian Zhang, Yongda Zhu

{"title":"First-star imprints in a metal-poor galaxy overdensity near the end of reionization","authors":"Zihao Li, Koki Kakiichi, Lise Christensen, Zheng Cai, Valentina D’Odorico, Jorryt Matthee, Daichi Kashino, Rongmon Bordoloi, Ruari Mackenzie, Trystyn A. M. Berg, Irene Vanni, Stefania Salvadori, Alessandra Venditti, Shiwu Zhang, Sarah E. I. Bosman, Eduardo Bañados, Frederick B. Davies, Xiaohui Fan, Hyunsung D. Jun, Xiangyu Jin, Mingyu Li, Sofía Rojas-Ruiz, Feige Wang, Jinyi Yang, Siwei Zou, Huanian Zhang, Yongda Zhu","doi":"10.1038/s41550-026-02993-5","DOIUrl":"https://doi.org/10.1038/s41550-026-02993-5","url":null,"abstract":"The first generation of stars, known as population III (Pop III), formed from primordial gas consisting solely of hydrogen and helium and is believed to have emerged only a few hundred million years after the Big Bang. Detecting the chemical enrichment of metal-poor circumgalactic gas offers a promising way to trace the enrichment signature of Pop III stars. Along the sight line to the quasar SDSS J0100+2802, a metal absorber at z = 5.945, showing over-abundant carbon and silicon compared with solar, has been reported to be consistent with the enrichment pattern of Pop III stars. Here, using data recorded by the James Webb Space Telescope, we report the discovery of an unusually metal-poor galaxy overdensity of 17 members (mean metallicity ~3% of solar) near this metal absorber, which is ~0.4 dex more metal-poor than coeval galaxies in similarly overdense environments. This less chemically evolved system may have provided favourable conditions for preserving the absorption signatures of Pop III enrichment. We infer a minimum dark matter halo mass of (mathrm{log}({M}_{{rm{h}},min }/{M}_{odot })=10.6{8}_{-1.72}^{+0.93}), supporting late-time Pop III formation at the outskirts of atomic hydrogen cooling haloes. Our findings open a promising observational pathway to identifying the chemical imprints of the first stars and constrain the conditions for their formation.","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"37 1","pages":""},"PeriodicalIF":14.1,"publicationDate":"2026-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149087859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Growth of aromatic hydrocarbon dust particles in the extremely metal-poor galaxy Sextans A 六分星A中极度缺乏金属的芳烃尘埃颗粒的生长

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2026-09-29 DOI: 10.1038/s41550-026-02969-5

Elizabeth J. Tarantino, Julia Roman-Duval, Karin M. Sandstrom, Cory M. Whitcomb, J.-D. T. Smith, Bruce T. Draine, Martha L. Boyer, Jérémy Chastenet, Ryan Chown, Christopher J. R. Clark, Meriem Elyajouri, Karl D. Gordon, Brandon S. Hensley, Thomas S.-Y. Lai, Christina W. Lindberg, Kristen B. W. McQuinn, Max J. B. Newman, O. Grace Telford, Dries Van De Putte, Benjamin F. Williams

{"title":"Growth of aromatic hydrocarbon dust particles in the extremely metal-poor galaxy Sextans A","authors":"Elizabeth J. Tarantino, Julia Roman-Duval, Karin M. Sandstrom, Cory M. Whitcomb, J.-D. T. Smith, Bruce T. Draine, Martha L. Boyer, Jérémy Chastenet, Ryan Chown, Christopher J. R. Clark, Meriem Elyajouri, Karl D. Gordon, Brandon S. Hensley, Thomas S.-Y. Lai, Christina W. Lindberg, Kristen B. W. McQuinn, Max J. B. Newman, O. Grace Telford, Dries Van De Putte, Benjamin F. Williams","doi":"10.1038/s41550-026-02969-5","DOIUrl":"https://doi.org/10.1038/s41550-026-02969-5","url":null,"abstract":"The mid-infrared spectrum of star-forming, high-metallicity galaxies is dominated by emission features from aromatic and aliphatic bonds in small carbonaceous dust grains, often referred to as polycyclic aromatic hydrocarbons (PAHs). In metal-poor galaxies, the abundance of PAHs relative to the total dust sharply declines, but the origin of this deficit is unknown. Here we present observations by the James Webb Space Telescope that detect and resolve emission from PAHs in the 7% solar metallicity galaxy Sextans A, representing, to our knowledge, the lowest metallicity detections of PAH emission known so far. In contrast to higher metallicity galaxies, the clumps of PAH emission are compact (0.5–1.5\" or 3–10 pc), which explains why PAH emission has evaded detection by lower resolution instruments. Ratios of the 3.3-μm, 7.7-μm and 11.3-μm PAH features indicate that the PAH grains in Sextans A are small and neutral, with no evidence of substantial processing from radiation fields. These results favour inhibited grain growth over enhanced destruction as the origin of the low PAH abundance in Sextans A. The compact clumps of PAH emission are likely active sites of in situ PAH growth within a dense, well-shielded phase of the interstellar medium. Our results show that PAHs can form and survive in the extremely metal-poor environments common early in the evolution of the Universe.","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"40 1","pages":""},"PeriodicalIF":14.1,"publicationDate":"2026-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149087860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Persistent primordial signature in present-day galaxies 现代星系中持续存在的原始特征

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2026-09-28 DOI: 10.1038/s41550-026-02979-3

Xi Kang

引用次数: 0

Beyond Hubble: revisiting the Hubble sequence across cosmic time 超越哈勃：穿越宇宙时间重访哈勃序列

IF 15.2 1区物理与天体物理

Nature Astronomy Pub Date : 2026-09-28 DOI: 10.1038/s41550-026-02989-1

Sandro Tacchella

引用次数: 0

Volatile depletion in rocky planets as a chemical fingerprint of hybrid accretion 岩石行星中挥发性耗竭作为混合吸积的化学指纹

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2026-09-25 DOI: 10.1038/s41550-026-02984-6

Haiyang S. Wang,Anders Johansen,Ziyan Xu,Marie-Luise Steinmeyer,Michiel Lambrechts,Elishevah van Kooten,Chao-Chin Yang,Zhaohuan Zhu,Dante S. Lauretta,Martin Bizzarro

引用次数: 0

ΛCDM in a courtroom ΛCDM在法庭上

IF 15.2 1区物理与天体物理

Nature Astronomy Pub Date : 2026-09-25 DOI: 10.1038/s41550-026-02977-5

Ofer Lahav, Paul Shah

引用次数: 0