Nature Astronomy最新文献

Determination of the mass distribution of the first stars from the 21-cm signal 从21厘米信号确定第一批恒星的质量分布

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2025-06-20 DOI: 10.1038/s41550-025-02575-x

T. Gessey-Jones, N. S. Sartorio, H. T. J. Bevins, A. Fialkov, W. J. Handley, E. de Lera Acedo, G. M. Mirouh, R. G. Izzard, R. Barkana

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Co-precession of a curved jet and compact accretion disk in M87 M87中弯曲射流与致密吸积盘的共进动

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2025-06-20 DOI: 10.1038/s41550-025-02580-0

Yuzhu Cui, Weikang Lin

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Fermi detection of gamma-ray emission from the hot coronae of radio-quiet active galactic nuclei 费米探测的伽马射线发射热日冕的无线电安静的活动星系核

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2025-06-20 DOI: 10.1038/s41550-025-02538-2

Jun-Rong Liu, Jian-Min Wang

{"title":"Fermi detection of gamma-ray emission from the hot coronae of radio-quiet active galactic nuclei","authors":"Jun-Rong Liu, Jian-Min Wang","doi":"10.1038/s41550-025-02538-2","DOIUrl":"https://doi.org/10.1038/s41550-025-02538-2","url":null,"abstract":"Relativistic jets around supermassive black holes are well-known powerful γ-ray emitters. In the absence of the jets in radio-quiet active galactic nuclei, how the supermassive black holes work in γ-ray bands is still unknown despite great observational efforts in the past three decades. Here, considering the previous efforts, we carefully select an active galactic nucleus sample composed of 37 nearby Seyfert galaxies with ultrahard X-rays for γ-ray detection by excluding all potential contamination in this band. Adopting a stacking technique, we report the significant γ-ray detection (test statistic 30.6, or 5.2σ) from the sample using 15-year Fermi-LAT observations. We find the average γ-ray luminosity of the sample to be (1.5 ± 1.0) × 1040 erg s−1 at energies of 1–300 GeV. Limited by the well-known pair production from the interaction of γ-rays with low-energy photons, γ-rays of more than several giga-electronvolts are found to originate from an extended corona (~2.7 × 106 gravitational radii), whereas the canonical much more compact X-ray corona (~10 gravitational radii) is responsible for γ-rays of one to several giga-electronvolts. The finding of the compact region lends strong support to the long-time theoretical expectations, but the extended corona is an unexpected finding. One promising scenario is that the electron–positron pairs produced in the compact X-ray corona would expand as a fireball, similar to that in γ-ray bursts, forming the structure of extended corona.","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"19 1","pages":""},"PeriodicalIF":14.1,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144329005","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

Black in galaxy astrophysics 星系天体物理学中的黑色

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2025-06-19 DOI: 10.1038/s41550-025-02581-z

Devontae C. Baxter, Arianna S. Long, Sinclaire M. Manning, Evan H. Nuñez, Zara Randriamanakoto, Gianni Sims

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Invisible spiral arms in Milky Way-like galaxies 银河系状星系中看不见的旋臂

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2025-06-19 DOI: 10.1038/s41550-025-02598-4

Bokyoung Kim

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Empowering voices and building bridges across the space community with Black In Astro 通过《Black In Astro》增强声音并在整个太空社区建立桥梁

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2025-06-19 DOI: 10.1038/s41550-025-02588-6

Naia Butler-Craig, Bryné Hadnott, KeShawn Ivory, Tana Joseph, AJ Link, Cheyenne Polius, Caprice L. Phillips, Dakotah Tyler, Ashley Walker, Robert Washington

引用次数: 0

Life might seem out of whack 生活似乎不正常

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2025-06-19 DOI: 10.1038/s41550-025-02601-y

Paul Woods

{"title":"Life might seem out of whack","authors":"Paul Woods","doi":"10.1038/s41550-025-02601-y","DOIUrl":"https://doi.org/10.1038/s41550-025-02601-y","url":null,"abstract":"A robust detection of life on another world would be a landmark event. A common approach towards life detection focuses on observing key chemical species in atmospheres that are uniquely associated with life. However, an alternative method involves identifying chemical disequilibrium: atmospheric chemistry that has been perturbed from thermodynamic equilibrium by some biological process. Amber Young and colleagues have simulated a present-day Earth orbiting another star to determine whether our ‘out of whack’ atmosphere would be detectable by JWST — and the answer is yes, under certain circumstances.Under this method, chemical disequilibrium is established by calculating the available Gibbs free energy (GFE) of a planet, which is the difference between the observed GFE and a theoretical equilibrium GFE for the same system. The observed GFE is a combination of observationally derived quantities, such as gas mixing ratios, global surface pressure, effective temperature, and physical properties of clouds, aerosols, and hazes in the atmosphere. The theoretical estimate is derived from essentially putting planetary ingredients into a ‘box’ and letting them settle. Earth’s main atmospheric ‘perturbation’ from equilibrium relates to the CH4–O2 system, where methane is a waste gas from metabolism. JWST/MIRI could not detect the ∼1 J mol−1 GFE offset of an Earth–Sun system. However, if the Earth were to transit an M dwarf (a TRAPPIST-1 analogue), the ~320 J mol−1 GFE offset would be detectable if a challenging part-per-million noise level could be achieved.","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"45 1","pages":""},"PeriodicalIF":14.1,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144329027","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 Juneteenth issue 六月号

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2025-06-19 DOI: 10.1038/s41550-025-02603-w

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Black in stellar astrophysics 恒星天体物理学中的黑色

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2025-06-19 DOI: 10.1038/s41550-025-02578-8

James O. Chibueze, Samaiyah Farid, India Jackson, Teresa Monsue, Miriam M. Nyamai

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A little red dot up close 一个小红点

IF 14.1 1区物理与天体物理

Nature Astronomy Pub Date : 2025-06-19 DOI: 10.1038/s41550-025-02599-3

Lindsay Oldham

{"title":"A little red dot up close","authors":"Lindsay Oldham","doi":"10.1038/s41550-025-02599-3","DOIUrl":"https://doi.org/10.1038/s41550-025-02599-3","url":null,"abstract":"Taking their name from their extremely red and compact emission, little red dots (LRDs) do not yet have a physical explanation that is consistent across their full spectral energy distribution (SED): whilst some spectral features indicate the presence of dusty active galactic nuclei (AGN), others are more naturally interpreted as stellar light. Observations and modelling are also often hampered by the high redshifts (z ≲ 5) at which most LRDs have been found. Bingjie Wang and colleagues present multiwavelength data for a likely LRD analogue at redshift z ~ 3, along with a feasible model for its structure.Combining JWST observations from multiple instruments with HST imaging and upper limits from Spitzer and Herschel data, the authors construct a range of spectrophotometric models with flexible treatment of the putative AGN and galaxy light. Though they cannot rule out a galaxy-only model, the high stellar mass implied by such a model would require an extreme stellar surface density and is an order of magnitude larger than the object’s estimated dynamical mass. Their joint galaxy–AGN model, on the other hand, depends on the dust in the AGN torus being unusually — but not unprecedently — cold. They also detect a blueshifted He I absorption feature, suggestive of an ionized outflow from the supermassive black hole (SMBH).","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"46 1","pages":""},"PeriodicalIF":14.1,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144329035","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