New Astronomy Reviews最新文献

A review on fundamental bounds and estimators for photometry and astrometry of celestial point sources using array detectors, from first principles 从第一性原理出发，综述了利用阵列探测器进行天体点源测光和天体测量的基本边界和估计

IF 26.8 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

New Astronomy Reviews

Pub Date : 2025-12-02 DOI: 10.1016/j.newar.2025.101745

Sebastián Espinosa , Rene A. Mendez , Jorge F. Silva , Marcos Orchard

Precise astrometric and photometric measurements of celestial point sources are fundamental to modern astronomy. These measurements, used to determine object positions, motions, and fluxes, are based on observational models that have evolved from empirical centroiding rules to rigorous probabilistic formulations at the pixel level. This review summarizes key contributions that formalized this transition and analyzes seminal works addressing both the theoretical limits and the empirical performance of estimators. Central to these developments is the derivation of fundamental bounds, such as the Cramér-Rao Lower Bound (CRLB), and the assessment of widely used estimators, including Maximum Likelihood (ML), Least Squares (LS), and Weighted Least Squares (WLS). These studies show that, while the CRLB sets a theoretical benchmark, practical estimators achieve it only under specific signal-to-noise ratio (SNR) regimes, with notable discrepancies in high-SNR conditions. Moreover, recent results demonstrate that jointly estimating source flux and background significantly improves photometric precision compared to sequential approaches. Looking ahead, the increasing complexity of astronomical surveys, driven by massive data volumes, dynamic observational conditions, and the integration of machine learning, poses new challenges to reliable inference. In this context, tools from statistical theory, including performance bounds and theoretically grounded estimators, remain critical to guide algorithm design and ensure robust astrometric and photometric pipelines.

对天体点源进行精确的天文测量和光度测量是现代天文学的基础。这些用于确定物体位置、运动和通量的测量是基于观测模型的，这些模型已经从经验质心规则发展到严格的像素级概率公式。这篇综述总结了形式化这一转变的关键贡献，并分析了解决理论限制和评估者的经验表现的开创性工作。这些发展的核心是基本边界的推导，例如cram - rao下限（CRLB），以及广泛使用的估计器的评估，包括最大似然（ML）、最小二乘（LS）和加权最小二乘（WLS）。这些研究表明，虽然CRLB设定了一个理论基准，但实际估计只能在特定的信噪比（SNR）制度下实现，在高信噪比条件下存在显著差异。此外，最近的研究结果表明，与顺序方法相比，联合估计源通量和背景可以显著提高光度精度。展望未来，在海量数据量、动态观测条件和机器学习集成的驱动下，天文调查的复杂性日益增加，对可靠的推断提出了新的挑战。在这种情况下，来自统计理论的工具，包括性能界限和理论基础估计器，对于指导算法设计和确保稳健的天体测量和光度测量管道仍然至关重要。

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引用次数: 0

Sublimation-driven dust activity of main-belt asteroids: Detection by spectral methods and analysis with numerical modeling of the reflectance spectra 主带小行星的升华驱动尘埃活动：光谱方法探测和反射光谱数值模拟分析

IF 26.8 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

New Astronomy Reviews

Pub Date : 2025-11-27 DOI: 10.1016/j.newar.2025.101735

Vladimir V. Busarev , Elena V. Petrova

We review the results of the spectrophotometric and multi-band photometric observations of main-belt asteroids aimed at searching for signs of sublimation-driven dust activity (SDA) and the analysis of these signs with numerical simulations of light scattering. The reflectance spectra of 17 main-belt asteroids out of 112 objects, which were observed near perihelion after 2012, exhibited the signs of activity as a temporary dust exosphere. Among these 17 asteroids, there are 12 primitive asteroids of C, F, B, P, and D spectral types with low-temperature mineralogy and a low geometric albedo (<0.10) and 5 asteroids predominantly of X-type with mixed mineralogy and a relatively high geometric albedo (>0.10). In our view, the most important result of these observations is that SDA was almost simultaneously detected in several asteroids for each of the observation periods, which apparently suggests that this phenomenon is frequent and widespread in the Solar System. We also discuss why in ground-based observations the spectral method is more sensitive than the direct imaging method in detecting the signs of a thin dust exosphere on main-belt asteroids. The registered reflectance spectra of asteroids were analyzed in comparison with numerically modeled spectra of an active asteroid enveloped by a dust exosphere containing particles of various composition and morphology. This comparison made it possible to obtain an insight into the properties of a formed temporary dust exosphere. Particularly, it has been found that the dust exosphere of an active asteroid may contain aggregate particles of different composition and structure rather than just homogenous submicron ice and dust particles. A relatively stable though temporary SDA in a primitive-type asteroid is apparently indicative of water-ice deposits located near the surface of the body. As our investigations suggest, on main-belt primitive asteroids, the mechanism of SDA often operates in conjunction with meteoroid impacts and the electrostatic field formed near the sunlit surface of the bodies. At the same time, flares and eruptive events on the Sun may considerably influence the shape and extension of the dust exosphere.

我们回顾了主带小行星的分光光度和多波段光度观测结果，旨在寻找升华驱动尘埃活动（SDA）的迹象，并利用光散射数值模拟分析这些迹象。2012年后在近日点附近观测到的112颗小行星中，有17颗主带小行星的反射光谱显示出作为临时尘埃外逸层活动的迹象。17颗小行星中，C、F、B、P、D光谱类型的原始小行星12颗，具有低温矿物学特征，低几何反照率（<0.10）； 5颗以x型为主，具有混合矿物学特征，较高的几何反照率（>0.10）。我们认为，这些观测最重要的结果是，在每个观测周期内，几乎同时在几颗小行星上检测到SDA，这显然表明这种现象在太阳系中是频繁和广泛的。我们还讨论了为什么在地面观测中，光谱方法比直接成像方法在探测主带小行星上薄尘埃外逸层的迹象时更敏感。对小行星的记录反射光谱进行了分析，并与一颗被含有不同成分和形态颗粒的尘埃外逸层包裹的活动小行星的数值模拟光谱进行了比较。这种比较使我们有可能深入了解形成的临时尘埃外逸层的特性。特别是，已经发现，活动小行星的尘埃外逸层可能含有不同组成和结构的聚集颗粒，而不仅仅是均匀的亚微米冰和尘埃颗粒。原始型小行星的相对稳定的SDA虽然是暂时的，但显然表明在天体表面附近有水冰沉积物。我们的研究表明，在主带原始小行星上，SDA的机制通常与流星体撞击和天体阳光照射表面附近形成的静电场相结合。与此同时，太阳上的耀斑和爆发事件可能会对尘埃外逸层的形状和延伸产生相当大的影响。

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引用次数: 0

Current opinions and trends in the search for extrasolar photosynthesis 研究太阳系外光合作用的当前观点和趋势

IF 26.8 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

New Astronomy Reviews

Pub Date : 2025-11-26 DOI: 10.1016/j.newar.2025.101736

Svetoslav Alexandrov , Juliana Ivanova , Kolyo Dankov

The search for extrasolar photosynthetic life is one of the most important goals for modern astrobiology. Recent discoveries of cold brown dwarfs, as well as planets orbiting M-, G-, K-, and F-type main-sequence stars, have expanded opportunities to search for photosynthetic biosignatures within their habitable zones. This comprehensive review synthesizes current knowledge and emerging trends in the field. The paper addresses stellar variability and how spectral energy distribution influences potential pigment evolution and photoprotective adaptations, whether photosynthetic life could exist on peculiar exoworlds with specific illumination and surface conditions, as well as observational strategies with current and future telescopes. The goal of this work is to help researchers navigate the vast sea of knowledge by providing a strategic roadmap for prioritizing targets and interpreting potential biosignatures.

寻找太阳系外的光合生命是现代天体生物学最重要的目标之一。最近发现的冷褐矮星，以及围绕M型、G型、K型和f型主序恒星运行的行星，扩大了在其可居住区域内寻找光合作用生物特征的机会。这篇全面的评论综合了该领域的当前知识和新兴趋势。本文讨论了恒星变异性和光谱能量分布如何影响潜在的色素进化和光保护适应性，光合生命是否可能存在于具有特定照明和表面条件的特殊系外世界，以及当前和未来望远镜的观测策略。这项工作的目标是通过提供优先考虑目标和解释潜在生物特征的战略路线图，帮助研究人员在浩瀚的知识海洋中导航。

引用次数: 0

Natal kicks of compact objects 致密物体的纳塔尔踢

IF 26.8 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

New Astronomy Reviews

Pub Date : 2025-10-27 DOI: 10.1016/j.newar.2025.101734

Sergei Popov , Bernhard Müller , Ilya Mandel

When compact objects – neutron stars and black holes – are formed in a supernova explosion, they may receive a high velocity at formation, which may reach or even exceed

1000

km s⁻¹ for neutron stars and hundreds of km s⁻¹ for black holes. The origin of the velocity kick is intimately related to supernova physics. A better understanding of kick properties from astronomical observations will shed light on the unsolved problems of these explosions, such as the exact conditions leading to exotic electron capture and ultra-stripped supernovae.

Kick velocities are profoundly important in several areas of astrophysics. Being a result of supernova explosions, the kick velocity distribution must be explained in the framework of the supernova mechanism. The kick magnitudes and directions influence many topics related to binary systems, including the rate of compact object coalescences observable through gravitational waves. Moreover, knowledge of the kick velocity distribution is significant in predicting future observational results and their interpretation. For example, it is expected that the Roman space telescope will discover many microlensing events related to neutron stars and black holes; accurate estimates of the number of observable microlensing events require precise kinematic properties of these compact objects.

当紧凑的物体——中子星和黑洞——在超新星爆炸中形成时，它们在形成时可能会获得很高的速度，中子星可能达到甚至超过1000 km s - 1，黑洞可能达到数百km s - 1。速度突升的起源与超新星物理学密切相关。从天文观测中更好地了解kick的特性将有助于揭示这些爆炸尚未解决的问题，例如导致奇异电子捕获和超剥离超新星的确切条件。在天体物理学的几个领域中，踢球速度是非常重要的。作为超新星爆炸的结果，踢速分布必须在超新星机制的框架内加以解释。踢的大小和方向影响许多与双星系统相关的主题，包括通过引力波观测到的致密物体合并的速率。此外，了解井涌速度分布对于预测未来的观测结果及其解释具有重要意义。例如，预计罗马太空望远镜将发现许多与中子星和黑洞有关的微透镜事件；准确估计可观测到的微透镜事件的数量需要这些致密物体的精确运动学特性。

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引用次数: 0

What drives the growth of black holes: A decade of progress 是什么推动了黑洞的增长：十年的进步

IF 26.8 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

New Astronomy Reviews

Pub Date : 2025-07-30 DOI: 10.1016/j.newar.2025.101733

D.M. Alexander , R.C. Hickox , J. Aird , F. Combes , T. Costa , M. Habouzit , C.M. Harrison , R.I. Leng , L.K. Morabito , S.L. Uckelman , P. Vickers

The last decade has witnessed significant progress in our understanding of the growth of super-massive black holes (SMBHs). It is now clear that an Active Galactic Nucleus (AGN: the observed manifestation of a growing SMBH) is an “event” within the broader lifecycle of a galaxy, which can significantly influence the shape and evolution of the galaxy itself. Our view of the obscuring medium that affects the observed properties of an AGN has also undergone a revolution, and we now have a more physical understanding of the connection between the fuelling of (and feedback from) the SMBH and the broader host-galaxy and larger-scale environment. We have a greater understanding of the physics of SMBH accretion, can identify AGNs out to

z =

8–10 witnessing the very earliest phases of SMBH growth, and have a more complete census of AGN activity than ever before. This great progress has been enabled by new innovative facilities, an ever-increasing quantity of multi-wavelength data, the exploitation and development of new techniques, and greater community-wide engagement. In this article we review our understanding of AGNs and the growth of SMBHs, providing an update of the earlier Alexander and Hickox (2012) review. Using citation-network analyses we also show where this review fits within the broader black-hole research literature and, adopting the previous article as a snapshot of the field over a decade ago, identify the drivers that have enabled the greatest scientific progress.

在过去的十年里，我们对超大质量黑洞（SMBHs）的理解取得了重大进展。现在很清楚，活动星系核（AGN：观测到的不断增长的SMBH的表现）是一个星系更广泛生命周期内的一个“事件”，它可以显著影响星系本身的形状和演化。我们对影响AGN观测属性的模糊介质的看法也经历了一场革命，我们现在对SMBH的燃料（和反馈）与更广泛的宿主星系和更大尺度环境之间的联系有了更多的物理理解。我们对SMBH吸积的物理学有了更深入的了解，可以识别出z= 8-10的AGN，见证了SMBH成长的最早阶段，并且对AGN活动有了比以往任何时候都更完整的普查。这一重大进展得益于新的创新设施、不断增加的多波长数据量、新技术的开发和发展，以及更广泛的社区参与。在本文中，我们回顾了我们对agn和SMBHs生长的理解，提供了早期Alexander和Hickox（2012）综述的更新。通过引用网络分析，我们还展示了这篇综述在更广泛的黑洞研究文献中的位置，并采用前一篇文章作为十多年前该领域的快照，确定了推动最大科学进步的驱动因素。

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引用次数: 0

Isolating Martian dust devils, dust storms, and water ice clouds through multi-satellite observations 通过多卫星观测分离火星尘卷风、沙尘暴和水冰云

IF 11.7 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

New Astronomy Reviews

Pub Date : 2025-04-07 DOI: 10.1016/j.newar.2025.101723

Jagabandhu Panda , Bijay Kumar Guha , Anirban Mandal , Claus Gebhardt , Zhaopeng Wu

Airborne dust and water ice clouds are the two major atmospheric constituents on Mars that have the most dynamic impact on its atmosphere. Airborne dust strongly alters atmospheric temperatures, therefore significantly impacting Martian weather and climate. Martian water ice clouds also have radiative impacts (both direct and via dust cycle feedbacks) and provide insight into the Martian water cycle and important questions about habitability and life. Satellite observations spanning more than two decades play a pivotal role in understanding the meteorological processes associated with airborne dust and water ice clouds on Mars. Therefore, this study reviews dust devils, dust storms, and water ice clouds with the help of imaging observations made by the sensors onboard different Mars orbiters. We discuss their characteristics, correlations, and inter-annual variation in general, in order to help support modeling and forecasting. The vertical distribution of dust and water ice and their dynamical, microphysical, and radiative interactions need more attention as well. The aim is to predict the thermal behavior of the atmosphere accurately, considering the complex interplay of dust and water ice forcing with temperature.

空气中的尘埃和水冰云是火星大气中的两大主要成分，对火星大气的动态影响最大。空气中的尘埃会强烈改变大气温度，从而对火星天气和气候产生重大影响。火星水冰云也会产生辐射影响（包括直接影响和通过尘埃循环反馈影响），并让人们深入了解火星水循环以及有关宜居性和生命的重要问题。二十多年的卫星观测在了解与火星空气尘埃和水冰云相关的气象过程方面发挥了关键作用。因此，本研究借助不同火星轨道器上的传感器进行的成像观测，对尘埃、尘暴和水冰云进行了回顾。我们从总体上讨论了它们的特征、相关性和年际变化，以帮助支持建模和预报。尘埃和水冰的垂直分布及其动力学、微物理和辐射相互作用也需要更多关注。目的是准确预测大气的热行为，同时考虑到尘埃和水冰与温度之间复杂的相互作用。

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引用次数: 0

Milky Way dynamics in light of Gaia 盖亚之光下的银河系动态

IF 11.7 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

New Astronomy Reviews

Pub Date : 2025-01-22 DOI: 10.1016/j.newar.2024.101721

Jason A.S. Hunt, Eugene Vasiliev

The Gaia mission has triggered major developments in the field of Galactic dynamics in recent years, which we discuss in this review. The structure and kinematics of all Galactic components – disc, bar/bulge and halo – are now mapped in great detail not only in the Solar neighbourhood, but across a large part of the Milky Way. The dramatic improvements in the coverage and precision of observations revealed various disequilibrium processes, such as perturbations in the Galactic disc and the deformations of the outer halo, which are partly attributed to the interaction with satellite galaxies. The knowledge of the gravitational potential at all scales has also advanced considerably, but we are still far from having a consistent view on the key properties of the Galaxy, such as the bar pattern speed or the mass profile and shape of the dark halo. The complexity and interplay of several dynamical processes makes the interpretation of observational data challenging, and it is fair to say that more theoretical effort is needed to fully reap the fruit of the Gaia revolution.

近年来，盖亚任务引发了银河系动力学领域的重大发展，我们在本文中进行了讨论。银河系所有组成部分的结构和运动学——盘状、棒状/凸起和光晕——现在不仅在太阳附近，而且在银河系的大部分地区都被绘制得非常详细。观测范围和精度的显著提高揭示了各种不平衡过程，例如银盘的扰动和外晕的变形，这些过程部分归因于与卫星星系的相互作用。所有尺度上的引力势的知识也有了相当大的进步，但我们对银河系的关键特性仍然没有一个一致的看法，比如条形速度或暗晕的质量轮廓和形状。几个动态过程的复杂性和相互作用使得观测数据的解释具有挑战性，公平地说，需要更多的理论努力才能充分收获盖亚革命的成果。

引用次数: 0

BBN-simple: How to bake a universe-sized cake bbn简单：如何烤一个宇宙大小的蛋糕

IF 11.7 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

New Astronomy Reviews

Pub Date : 2025-01-15 DOI: 10.1016/j.newar.2025.101722

Aidan Meador-Woodruff , Dragan Huterer

Big Bang Nucleosynthesis (BBN), the process of creation of lightest elements in the early universe, is a highly robust, precise, and ultimately successful theory that forms one of the three pillars of the standard hot-Big-Bang cosmological model. Existing theoretical treatments of BBN and the associated computer codes are accurate and flexible, but are typically highly technical and opaque, and not suitable for pedagogical understanding of the BBN. Here we present BBN-simple – a from-scratch numerical calculation of the lightest element abundances pitched at an advanced undergraduate or beginning graduate level. We review the physics of the early universe relevant for BBN, provide information about the reaction rates, and discuss computational-mathematics background that is essential in setting up a BBN calculation. We calculate the abundances of the principal nuclear species in a standard cosmological model, and find a reasonably good agreement with public precision-level BBN codes. A condensed version of this paper and associated snippets of computer code are given at http://www-personal.umich.edu/~aidanmw/.

大爆炸核合成（BBN）是早期宇宙中产生最轻元素的过程，是一个高度稳健、精确、最终成功的理论，它构成了标准热大爆炸宇宙模型的三大支柱之一。现有的理论处理BBN和相关的计算机代码是准确和灵活的，但通常是高度技术性和不透明的，不适合对BBN的教学理解。在这里，我们提出了BBN-simple -一个从头开始的最轻元素丰度的数值计算，适用于高级本科或研究生初级水平。我们回顾了与BBN相关的早期宇宙物理学，提供了有关反应速率的信息，并讨论了建立BBN计算所必需的计算数学背景。我们计算了标准宇宙学模型中主要核物质的丰度，并找到了与公共精度级BBN代码相当好的一致性。本文的精简版本和相关的计算机代码片段可在http://www-personal.umich.edu/~aidanmw/上找到。

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引用次数: 0

Martian hydrosphere: A brief overview of water on Mars 火星水圈：火星上的水的简要概述

IF 11.7 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

New Astronomy Reviews

Pub Date : 2024-11-29 DOI: 10.1016/j.newar.2024.101714

Brahma Gopalchetty

Understanding the status of water on Mars is crucial for evaluating its capacity to support life and to serve as a resource for future possible human exploration. Investigations have been carried out in the past to find signs of water in its past or present states. It is generally agreed that Mars had significant amounts of water early in its existence, but today, only remnants exist, mostly as ice or within hydrous minerals. Current evidence of water on Mars includes geological features, Martian meteorites, sporadic wet flows on slopes, surface moisture detected by missions like Curiosity and Phoenix, and features suggesting ancient lakes and rivers. A notable recent discovery was an old streambed in Gale Crater, indicating the presence of considerable water flow in the past, which might have supported microbial life. Nowadays, Mars' arid surface is not suitable for life as we know it, leading scientists to focus on underground environments for the exploration of life and its respective biosignatures. Recent efforts have unveiled substantial underground ice reserves discovered by NASA in 2016 and a hidden subglacial lake identified by Italian researchers in 2018. The question of life on Mars still remains unresolved to date. This overview compiles the findings from diverse studies on Mars' water history and attempts to address the ongoing discussions about the potential for life on the planet.

了解火星上的水的状况对于评估其支持生命的能力以及作为未来可能的人类探索的资源至关重要。过去曾进行过调查，以寻找过去或现在状态下存在水的迹象。人们普遍认为，火星早期存在大量的水，但今天，只有残余物存在，主要以冰或含水矿物的形式存在。目前火星上存在水的证据包括地质特征、火星陨石、斜坡上零星的湿流、“好奇号”和“凤凰号”等任务探测到的火星表面水分，以及暗示古代湖泊和河流的特征。最近一个引人注目的发现是盖尔陨坑里有一个古老的河床，这表明过去有相当多的水流存在，这可能支持了微生物的生命。如今，正如我们所知，火星干旱的表面不适合生命生存，这使得科学家们把重点放在了地下环境上，以探索生命及其各自的生物特征。最近的努力揭示了美国宇航局在2016年发现的大量地下冰储备，以及意大利研究人员在2018年发现的一个隐藏的冰下湖。迄今为止，火星上是否有生命的问题仍未得到解决。这篇综述汇编了关于火星水历史的各种研究结果，并试图解决关于火星上可能存在生命的讨论。

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引用次数: 0

Stellar streams in the Gaia era 盖亚时代的恒星流

IF 11.7 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

New Astronomy Reviews

Pub Date : 2024-11-28 DOI: 10.1016/j.newar.2024.101713

Ana Bonaca , Adrian M. Price-Whelan

The hierarchical model of galaxy formation predicts that the Milky Way halo is populated by tidal debris of dwarf galaxies and globular clusters. Due to long dynamical times, debris from the lowest mass objects remains coherent as thin and dynamically cold stellar streams for billions of years. The Gaia mission, providing astrometry and spectrophotometry for billions of stars, has brought three fundamental changes to our view of cold stellar streams in the Milky Way. First, more than a hundred stellar streams have been discovered and characterized using Gaia data. This is an order of magnitude increase in the number of well-measured streams, thanks to Gaia’s capacity for identifying comoving groups of stars among the field Milky Way population. Second, Gaia data have revealed that density variations both along and across stellar streams are common. Dark-matter subhalos, as well as baryonic structures were theoretically predicted to form such features, but observational evidence for density variations was uncertain before Gaia. Third, stream kinematics are now widely available and have constrained the streams’ orbits and origins. Gaia has not only provided proper motions directly, but also enabled efficient spectroscopic follow-up of the proper-motion selected targets. These discoveries have established stellar streams as a dense web of sensitive gravitational tracers in the Milky Way halo. We expect the coming decade to bring a full mapping of the Galactic population of stellar streams, as well as develop numerical models that accurately explain their evolution within the Milky Way for a variety of cosmological models. Perhaps most excitingly, the comparison between the two will be able to reveal the presence of dark-matter subhalos below the threshold for galaxy formation (

≲ 1 0^{6} M_{⊙}

), and provide the most stringent test of the cold dark matter paradigm on small scales.

星系形成的分层模型预测，银河系晕是由矮星系和球状星团的潮汐碎片组成的。由于长期的动态时间，来自最低质量物体的碎片在数十亿年的时间里保持着稀薄和动态冷恒星流的一致性。盖亚任务为数十亿颗恒星提供了天体测量和分光光度法，它给我们对银河系冷恒星流的看法带来了三个根本性的变化。首先，利用盖亚的数据已经发现并描述了一百多个恒星流。由于盖亚有能力在银河系中识别移动的恒星群，这是精确测量流数量的一个数量级增加。其次，盖亚的数据揭示了沿恒星流和跨恒星流的密度变化是很常见的。理论上，暗物质亚晕和重子结构被预测会形成这样的特征，但在盖亚之前，密度变化的观测证据并不确定。第三，流的运动学现在广泛可用，并且约束了流的轨道和起源。盖亚不仅直接提供了适当的运动，而且能够对适当运动的选定目标进行有效的光谱跟踪。这些发现已经将恒星流确定为银河系晕中由敏感引力示踪剂组成的密集网。我们期望在未来的十年里，我们能够绘制出银河系恒星流的完整地图，并开发出能够准确解释恒星流在银河系内演化的各种宇宙学模型的数值模型。也许最令人兴奋的是，两者之间的比较将能够揭示暗物质亚晕的存在，低于星系形成的阈值（> 106M⊙），并在小尺度上对冷暗物质范式提供最严格的测试。

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引用次数: 0