Pub Date : 2024-08-14DOI: 10.1038/s41550-024-02352-2
Bishwanath Gaire
{"title":"Magnetic field enhancement within a remnant","authors":"Bishwanath Gaire","doi":"10.1038/s41550-024-02352-2","DOIUrl":"10.1038/s41550-024-02352-2","url":null,"abstract":"","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"8 8","pages":"943-943"},"PeriodicalIF":12.9,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141980835","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}
Pub Date : 2024-08-14DOI: 10.1038/s41550-024-02353-1
Paul Woods
{"title":"Model test for very-metal-poor giant","authors":"Paul Woods","doi":"10.1038/s41550-024-02353-1","DOIUrl":"10.1038/s41550-024-02353-1","url":null,"abstract":"","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"8 8","pages":"944-944"},"PeriodicalIF":12.9,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141980924","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}
Pub Date : 2024-08-12DOI: 10.1038/s41550-024-02337-1
Mark R. Krumholz, Roland M. Crocker, Arash Bahramian, Pol Bordas
The propagation directions of cosmic rays travelling through interstellar space are repeatedly scattered by fluctuating interstellar magnetic fields. The nature of this scattering is a major unsolved problem in astrophysics, one that has resisted solution largely due to a lack of direct observational constraints on the scattering rate. Here we show that very high-energy γ-ray emission from the globular cluster Terzan 5, which has unexpectedly been found to be displaced from the cluster, presents a direct probe of this process. We show that this displacement is naturally explained by cosmic rays accelerated in the bow shock around the cluster, which then propagate a finite distance before scattering processes re-orient enough of them towards Earth to produce a detectable γ-ray signal. The angular distance between the cluster and the signal places tight constraints on the scattering rate, which we show are consistent with a model in which scattering is primarily due to excitation of magnetic waves by the cosmic rays themselves. The analysis method we develop here will make it possible to use sources with similarly displaced non-thermal X-ray and tera-electronvolt γ-ray signals as direct probes of cosmic ray scattering across a range of Galactic environments. How a star cluster manages to produce γ-rays at a location 30 light yr away from itself is a mystery that can be solved by carefully testing theories about how charged particles travel through space.
宇宙射线穿过星际空间时，其传播方向会被波动的星际磁场反复散射。这种散射的性质是天体物理学中一个尚未解决的重大问题，主要由于缺乏对散射率的直接观测约束，这个问题一直没有得到解决。在这里，我们展示了来自球状星团 Terzan 5 的高能 γ 射线辐射，它是对这一过程的直接探测。我们的研究表明，这种位移可以很自然地解释为宇宙射线在星团周围的弓形冲击中被加速，然后传播一段有限的距离，然后散射过程将足够多的宇宙射线重新定向到地球，从而产生可探测到的γ射线信号。星团和信号之间的角距离对散射率有严格的限制，我们的研究表明，这与散射主要是由于宇宙射线本身激发磁波的模型是一致的。我们在这里开发的分析方法将使我们有可能利用具有类似位移的非热 X 射线和太电子伏特 γ 射线信号源来直接探测一系列银河环境中的宇宙射线散射。
{"title":"Teraelectronvolt gamma-ray emission near globular cluster Terzan 5 as a probe of cosmic ray transport","authors":"Mark R. Krumholz, Roland M. Crocker, Arash Bahramian, Pol Bordas","doi":"10.1038/s41550-024-02337-1","DOIUrl":"10.1038/s41550-024-02337-1","url":null,"abstract":"The propagation directions of cosmic rays travelling through interstellar space are repeatedly scattered by fluctuating interstellar magnetic fields. The nature of this scattering is a major unsolved problem in astrophysics, one that has resisted solution largely due to a lack of direct observational constraints on the scattering rate. Here we show that very high-energy γ-ray emission from the globular cluster Terzan 5, which has unexpectedly been found to be displaced from the cluster, presents a direct probe of this process. We show that this displacement is naturally explained by cosmic rays accelerated in the bow shock around the cluster, which then propagate a finite distance before scattering processes re-orient enough of them towards Earth to produce a detectable γ-ray signal. The angular distance between the cluster and the signal places tight constraints on the scattering rate, which we show are consistent with a model in which scattering is primarily due to excitation of magnetic waves by the cosmic rays themselves. The analysis method we develop here will make it possible to use sources with similarly displaced non-thermal X-ray and tera-electronvolt γ-ray signals as direct probes of cosmic ray scattering across a range of Galactic environments. How a star cluster manages to produce γ-rays at a location 30 light yr away from itself is a mystery that can be solved by carefully testing theories about how charged particles travel through space.","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"8 10","pages":"1284-1293"},"PeriodicalIF":12.9,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141918771","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}
Pub Date : 2024-08-07DOI: 10.1038/s41550-024-02336-2
Franco Vazza
Giant shock waves at the physical boundaries of the most massive structures in the Universe could be used as an accurate tool to measure the total mass of clusters of galaxies.
宇宙中最大质量结构物理边界上的巨型冲击波可以作为精确测量星系团总质量的工具。
{"title":"Weighing galaxy clusters with shocks","authors":"Franco Vazza","doi":"10.1038/s41550-024-02336-2","DOIUrl":"10.1038/s41550-024-02336-2","url":null,"abstract":"Giant shock waves at the physical boundaries of the most massive structures in the Universe could be used as an accurate tool to measure the total mass of clusters of galaxies.","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"8 9","pages":"1075-1076"},"PeriodicalIF":12.9,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141899453","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}
Pub Date : 2024-08-05DOI: 10.1038/s41550-024-02338-0
Jakob Stegmann, Lorenz Zwick, Sander M. Vermeulen, Fabio Antonini, Lucio Mayer
The most massive black holes in our Universe form binaries at the centre of merging galaxies. The recent evidence for a gravitational-wave (GW) background from pulsar timing may constitute the first observation that these supermassive black-hole binaries (SMBHBs) merge. Yet, the most massive SMBHBs are out of reach of interferometric GW detectors and are exceedingly difficult to resolve individually with pulsar timing. These limitations call for unexplored strategies to detect individual SMBHBs in the uncharted frequency band ≲10−5 Hz to establish their abundance and decipher the coevolution with their host galaxies. Here we show that SMBHBs imprint detectable long-term modulations on GWs from stellar-mass binaries residing in the same galaxy at a distance d ≲ 1 kpc. We determine that proposed decihertz GW interferometers sensitive to numerous stellar-mass binaries could uncover modulations from ~O(10−1–104) SMBHBs with masses ~O(107–108) M⊙out to redshift z ≈ 3.5. This offers a unique opportunity to map the population of SMBHBs through cosmic time, which might remain inaccessible otherwise. Merging supermassive black holes emit low-frequency gravitational waves, difficult to observe with current and future detectors. Stegmann et al. show that these black holes can leave measurable traces in high-frequency signals from adjacent sources.
{"title":"Imprints of massive black-hole binaries on neighbouring decihertz gravitational-wave sources","authors":"Jakob Stegmann, Lorenz Zwick, Sander M. Vermeulen, Fabio Antonini, Lucio Mayer","doi":"10.1038/s41550-024-02338-0","DOIUrl":"10.1038/s41550-024-02338-0","url":null,"abstract":"The most massive black holes in our Universe form binaries at the centre of merging galaxies. The recent evidence for a gravitational-wave (GW) background from pulsar timing may constitute the first observation that these supermassive black-hole binaries (SMBHBs) merge. Yet, the most massive SMBHBs are out of reach of interferometric GW detectors and are exceedingly difficult to resolve individually with pulsar timing. These limitations call for unexplored strategies to detect individual SMBHBs in the uncharted frequency band ≲10−5 Hz to establish their abundance and decipher the coevolution with their host galaxies. Here we show that SMBHBs imprint detectable long-term modulations on GWs from stellar-mass binaries residing in the same galaxy at a distance d ≲ 1 kpc. We determine that proposed decihertz GW interferometers sensitive to numerous stellar-mass binaries could uncover modulations from ~O(10−1–104) SMBHBs with masses ~O(107–108) M⊙out to redshift z ≈ 3.5. This offers a unique opportunity to map the population of SMBHBs through cosmic time, which might remain inaccessible otherwise. Merging supermassive black holes emit low-frequency gravitational waves, difficult to observe with current and future detectors. Stegmann et al. show that these black holes can leave measurable traces in high-frequency signals from adjacent sources.","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"8 10","pages":"1321-1331"},"PeriodicalIF":12.9,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41550-024-02338-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141895227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-02DOI: 10.1038/s41550-024-02348-y
T. Cavalié, L. Rezac, R. Moreno, E. Lellouch, T. Fouchet, B. Benmahi, T. K. Greathouse, J. A. Sinclair, V. Hue, P. Hartogh, M. Dobrijevic, N. Carrasco, Z. Perrin
{"title":"Author Correction: Evidence for auroral influence on Jupiter’s nitrogen and oxygen chemistry revealed by ALMA","authors":"T. Cavalié, L. Rezac, R. Moreno, E. Lellouch, T. Fouchet, B. Benmahi, T. K. Greathouse, J. A. Sinclair, V. Hue, P. Hartogh, M. Dobrijevic, N. Carrasco, Z. Perrin","doi":"10.1038/s41550-024-02348-y","DOIUrl":"10.1038/s41550-024-02348-y","url":null,"abstract":"","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"8 9","pages":"1206-1206"},"PeriodicalIF":12.9,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41550-024-02348-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142273355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1038/s41550-024-02334-4
Niels F. W. Ligterink, Paola Pinilla, Nienke van der Marel, Jeroen Terwisscha van Scheltinga, Alice S. Booth, Conel M. O’D. Alexander, My E. I. Riebe
Organic macromolecular matter is the dominant carrier of volatile elements such as carbon, nitrogen and noble gases in chondrites—the rocky building blocks from which Earth formed. How this macromolecular substance formed in space is unclear. Here we show that its formation could be associated with the presence of dust traps, which are prominent mechanisms for forming planetesimals in planet-forming disks. We demonstrate the existence of heavily irradiated zones in dust traps, where small frozen molecules that coat large quantities of microscopic dust grains could be rapidly converted into macromolecular matter by receiving radiation doses of up to several tens of electronvolts per molecule per year. This allows for the transformation of simple molecules into complex macromolecular matter within several decades. Up to roughly 4% of the total disk ice reservoir can be processed this way and subsequently incorporated into the protoplanetary disk midplane where planetesimals form. This finding shows that planetesimal formation and the production of organic macromolecular matter, which provides the essential elemental building blocks for life, might be linked. The organic macromolecular matter found in meteorites could have formed in heavily irradiated zones in dust traps in planet-forming disks, according to an evolutionary model of a protoplanetary disk.
{"title":"The rapid formation of macromolecules in irradiated ice of protoplanetary disk dust traps","authors":"Niels F. W. Ligterink, Paola Pinilla, Nienke van der Marel, Jeroen Terwisscha van Scheltinga, Alice S. Booth, Conel M. O’D. Alexander, My E. I. Riebe","doi":"10.1038/s41550-024-02334-4","DOIUrl":"10.1038/s41550-024-02334-4","url":null,"abstract":"Organic macromolecular matter is the dominant carrier of volatile elements such as carbon, nitrogen and noble gases in chondrites—the rocky building blocks from which Earth formed. How this macromolecular substance formed in space is unclear. Here we show that its formation could be associated with the presence of dust traps, which are prominent mechanisms for forming planetesimals in planet-forming disks. We demonstrate the existence of heavily irradiated zones in dust traps, where small frozen molecules that coat large quantities of microscopic dust grains could be rapidly converted into macromolecular matter by receiving radiation doses of up to several tens of electronvolts per molecule per year. This allows for the transformation of simple molecules into complex macromolecular matter within several decades. Up to roughly 4% of the total disk ice reservoir can be processed this way and subsequently incorporated into the protoplanetary disk midplane where planetesimals form. This finding shows that planetesimal formation and the production of organic macromolecular matter, which provides the essential elemental building blocks for life, might be linked. The organic macromolecular matter found in meteorites could have formed in heavily irradiated zones in dust traps in planet-forming disks, according to an evolutionary model of a protoplanetary disk.","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"8 10","pages":"1257-1263"},"PeriodicalIF":12.9,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141794604","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}
Pub Date : 2024-07-24DOI: 10.1038/s41550-024-02287-8
Mikhail Dobynde, Jingnan Guo
The effects of harmful space radiation are one of the biggest concerns for future lunar explorers. Here, we use a data-validated model, the Radiation Environment and Dose on the Moon (REDMoon), to create mission schedules for different scenarios of lunar bases limited by radiation constraints. We consider habitats at the surface and subsurface of the Moon with different regolith and aluminium shielding using the last two solar cycles (2000–2022) as a baseline. The exposure due to background galactic cosmic rays (GCRs) is about 66% on the lunar surface than in interplanetary space and can even slightly increase beneath the surface before it decreases to a negligible value at about 3 m depth. If the shielding is insufficient, the surface dose during a single solar particle event could sometimes exceed annual GCR exposure, leading to an immediate replacement of the crew. Our work provides radiation-mitigation considerations for future human lunar bases and exploration cost estimates. A data-validated model for the lunar radiation environment is used to draw guidelines for safe future activities on the Moon, depending on the thickness and type of habitat shielding. Unless the base is at a depth of at least 3 m, some degree of crew rotation is needed, up to several times per year.
{"title":"Guidelines for radiation-safe human activities on the Moon","authors":"Mikhail Dobynde, Jingnan Guo","doi":"10.1038/s41550-024-02287-8","DOIUrl":"10.1038/s41550-024-02287-8","url":null,"abstract":"The effects of harmful space radiation are one of the biggest concerns for future lunar explorers. Here, we use a data-validated model, the Radiation Environment and Dose on the Moon (REDMoon), to create mission schedules for different scenarios of lunar bases limited by radiation constraints. We consider habitats at the surface and subsurface of the Moon with different regolith and aluminium shielding using the last two solar cycles (2000–2022) as a baseline. The exposure due to background galactic cosmic rays (GCRs) is about 66% on the lunar surface than in interplanetary space and can even slightly increase beneath the surface before it decreases to a negligible value at about 3 m depth. If the shielding is insufficient, the surface dose during a single solar particle event could sometimes exceed annual GCR exposure, leading to an immediate replacement of the crew. Our work provides radiation-mitigation considerations for future human lunar bases and exploration cost estimates. A data-validated model for the lunar radiation environment is used to draw guidelines for safe future activities on the Moon, depending on the thickness and type of habitat shielding. Unless the base is at a depth of at least 3 m, some degree of crew rotation is needed, up to several times per year.","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"8 8","pages":"991-999"},"PeriodicalIF":12.9,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141764013","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}
Pub Date : 2024-07-22DOI: 10.1038/s41550-024-02332-6
Morgan Hollis
{"title":"Red and definitely not dead in the early Universe","authors":"Morgan Hollis","doi":"10.1038/s41550-024-02332-6","DOIUrl":"10.1038/s41550-024-02332-6","url":null,"abstract":"","PeriodicalId":18778,"journal":{"name":"Nature Astronomy","volume":"8 7","pages":"804-804"},"PeriodicalIF":12.9,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141750282","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}
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