編譯|未玖
Nature, 29 May 2025, Volume 641, Issue 8065
《自然》2025年5月29日，第641卷，8065期
天文學Astronomy
Quasar radiation transforms the gas in a merging companion galaxy
類星體輻射改變合并伴星系氣體性質
▲ 作者：Sergei Balashev, Pasquier Noterdaeme, Neeraj Gupta, Jens-Kristian Krogager, Fran?oise Combes, Sebastián López, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-08966-4
▲摘要：
類星體由超大質量黑洞的氣體吸積供能，是宇宙中能量最高的天體之一。雖然類星體被認為由星系合并引發，并影響周圍的氣體，但對這兩個過程的觀測限制仍然很少。
研究組報道了一個紅移z≈2.7的主要合并系統，并證明一個星系中類星體的輻射直接改變了另一個星系的氣體性質。該發現表明，這些星系質量巨大，質心相距只有幾千秒差距，以550 km s-1的速度彼此接近，它們正在形成恒星，并含有大量的分子質量。
然而，在類星體核的吸收中觀測到的塵埃分子氣體被高度激發，并被限制在密度約為105至106 cm?3、尺寸小于0.02 pc的小云團中，這比在干擾（非類星體）環境中觀察到的要緊湊幾個數量級。這也比目前通過高紅移分子線發射可分辨的小約105倍。
研究組推斷，無論在哪里暴露于類星體輻射，分子氣體都會被破壞，留下幸存的致密云太小以至于無法產生新的恒星。該研究結果不僅強調了主要星系合并在觸發類星體活動中的作用，還揭示了局部負反饋作為內部氣體結構的深刻改變，這可能阻礙了恒星的形成。
▲ Abstract：
Quasars, powered by gas accretion onto supermassive black holes, rank among the most energetic objects in the Universe. Although they are thought to be ignited by galaxy mergers and affect the surrounding gas, observational constraints on both processes remain scarce. Here we describe a major merging system at redshift z?≈?2.7 and demonstrate that radiation from the quasar in one galaxy directly alters the gas properties in the other galaxy. Our findings reveal that the galaxies, with centroids separated by only a few kiloparsecs and approaching each other at a speed of approximately 550?km?s?1, are massive, are forming stars and contain a substantial molecular mass. Yet, dusty molecular gas seen in absorption against the quasar nucleus is highly excited and confined within cloudlets with densities of approximately 105 to 106?cm?3 and sizes of less than 0.02?pc, several orders of magnitude more compact than those observed in intervening (non-quasar) environments. This is also approximately 105 times smaller than currently resolvable through molecular-line emission at high redshifts. We infer that, wherever it is exposed to the quasar radiation, the molecular gas is disrupted, leaving behind surviving dense clouds too small to give birth to new stars. Our results not only underscore the role of major galaxy mergers in triggering quasar activity but also reveal localized negative feedback as a profound alteration of the internal gas structure, which probably hampers star formation.
Thermal asymmetry in the Moon’s mantle inferred from monthly tidal response
從每月潮汐響應推斷月球地幔的熱不對稱性
▲ 作者：R. S. Park, A. Berne, A. S. Konopliv, J. T. Keane, I. Matsuyama, F. Nimmo, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-08949-5
▲摘要：
月球因繞地球的偏心和傾斜軌道而經歷了周期性的潮汐強迫。這種潮汐相互作用的響應驅動了月球重力場的時間變化，并且對衛星的內部結構很敏感。
研究組使用美國航空航天局GRAIL航天器的數據來恢復隨時間變化的月球重力場，包括3級引力潮汐勒夫數k3。他們報告了k3 = 0.0163±0.0007的估計值，這比球對稱衛星的估計值高出約72%。
當地幔的彈性剪切模量在近端和遠端之間的變化約為2~3%時，才能解釋如此大的k3，該觀測證明了月球深部內部的橫向非均質性。這種不對稱結構表明，在近側地幔中保存了大約100~200K的主要熱異常，該異常在30~40億年前形成了地表月海區域，并可能影響深月震的空間分布。
▲ Abstract：
The Moon undergoes periodic tidal forcing due to its eccentric and oblique orbit around the Earth. The response to this tidal interaction drives temporal changes in the lunar gravity field and is sensitive to the satellite’s internal structure. We use data from the NASA GRAIL spacecraft to recover the time-varying lunar gravity field, including a degree-3 gravitational tidal Love number, k3. Here, we report our estimated value of k3?=?0.0163?±?0.0007, which is about 72% higher than that expected for a spherically symmetric moon. Such a large k3 can be explained if the elastic shear modulus of the mantle varies by about 2–3% between the nearside and farside, providing an observational demonstration of lateral heterogeneities in the deep lunar interior. This asymmetric structure suggests preservation of a predominantly thermal anomaly of roughly 100–200?K in the nearside mantle that formed surface mare regions 3–4?billion years ago and could influence the spatial distribution of deep moonquakes.
材料科學Material Science
Hidden states and dynamics of fractional fillings in twisted MoTe2 bilayers
扭角雙層MoTe2中分數填充的隱藏態和動力學
▲ 作者：Yiping Wang, Jeongheon Choe, Eric Anderson, Weijie Li, Julian Ingham, Eric A. Arsenault, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-08954-8
▲摘要：
近年來人們在扭角雙層MoTe2（tMoTe2）中發現了分數量子反常霍爾（FQAH）效應。到目前為止，實驗已發現了在ν =?1、?2/3、?3/5和?4/7（每莫爾晶胞）處空穴摻雜的陳氏絕緣體。同時，理論預測，在v =?1和?3之間存在奇異量子相，如極難獲得的分數拓撲絕緣體、分數量子自旋霍爾（FQSH）態和非阿貝爾分數態。
研究組使用瞬態光學光譜對tMoTe2進行分析，揭示了在靜態光學傳感或傳輸測量中不存在的分數填充處的近20個隱藏態。泵浦脈沖選擇性地激發相關或贗能隙上的電荷，導致相關態的無序（熔化）。探針脈沖通過激子和三激子感應來檢測隨后的熔化和恢復動力學。
除了已知的狀態外，研究組還觀察到ν=0和?1之間的分數填充和電子摻雜側（ν>0）的大量態。最重要的是，還在ν=?4/3、?3/2、?5/3、?7/3、?5/2和?8/3的陳氏帶分數填充處觀察到新的態。這些態是預測奇異拓撲相的潛在候選者。
此外，研究組發現關聯態的熔化發生在2~4 ps和180~270 ps兩個不同的時間尺度上，這分別歸因于電子和聲子機制。他們從不同的莫爾導帶和價帶討論了電子摻雜態和空穴摻雜態的不同動力學。
▲ Abstract：
The fractional quantum anomalous Hall (FQAH) effect was recently discovered in twisted MoTe2 (tMoTe2) bilayers. Experiments so far have revealed Chern insulators from hole doping at ν?=??1, ?2/3, ?3/5 and ?4/7 (per moiré unit cell). In parallel, theories predict that, between v?=??1 and ?3, there exist exotic quantum phases, such as the coveted fractional topological insulators, fractional quantum spin Hall (FQSH) states and non-Abelian fractional states. Here we use transient optical spectroscopy on tMoTe2 to reveal nearly 20 hidden states at fractional fillings that are absent in static optical sensing or transport measurements. A pump pulse selectively excites charge across the correlated or pseudogaps, leading to the disordering (melting) of correlated states. A probe pulse detects the subsequent melting and recovery dynamics by means of exciton and trion sensing. Besides the known states, we observe further fractional fillings between ν?=?0 and ?1 and a large number of states on the electron doping side (ν?>?0). Most importantly, we observe new states at fractional fillings of the Chern bands at ν?=??4/3, ?3/2, ?5/3, ?7/3, ?5/2 and ?8/3. These states are potential candidates for the predicted exotic topological phases. Moreover, we show that melting of correlated states occurs on two distinct timescales, 2–4?ps and 180–270?ps, attributed to electronic and phonon mechanisms, respectively. We discuss the differing dynamics of the electron-doped and hole-doped states from the distinct moiré conduction and valence bands.
化學Chemistry
Encapsulated Co–Ni alloy boosts high-temperature CO2 electroreduction
封裝Co-Ni合金促進高溫CO2電還原
▲ 作者：Wenchao Ma, Jordi Morales-Vidal, Jiaming Tian, Meng-Ting Liu, Seongmin Jin, Wenhao Ren, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-08978-0
▲摘要：
電化學將CO2還原為化學物質和燃料在可再生能源儲存和碳回收方面具有很大的前景。雖然固體氧化物電解池中的高溫CO2電還原具有工業價值，但當前催化劑在1 A cm-2的高電流密度和800℃及更高的溫度下能效低于70%，壽命僅為200 h。
研究組開發了一種使用Sm2O3摻雜CeO2封裝的Co-Ni合金催化劑，在800℃高溫、1 A cm-2的電流密度下，CO2轉化為CO的能量效率為90%，壽命超過2000小時。其對CO的選擇性約為100%，單程收率達90%。
研究結果表明，該催化劑的能效源于其獨特的封裝結構和優化的合金組成，能夠同時增強CO2吸附、適度CO吸附和抑制金屬團聚。這項工作為高溫反應催化劑的設計提供了一種有效的策略，克服了活性和穩定性之間的傳統權衡，具有潛在的工業應用價值。
▲ Abstract：
Electrochemical CO2 reduction into chemicals and fuels holds great promise for renewable energy storage and carbon recycling. Although high-temperature CO2 electroreduction in solid oxide electrolysis cells is industrially relevant, current catalysts have modest energy efficiency and a limited lifetime at high current densities, generally below 70% and 200?h, respectively, at 1?A?cm?2 and temperatures of 800?°C or higher. Here we develop an encapsulated Co–Ni alloy catalyst using Sm2O3-doped CeO2 that exhibits an energy efficiency of 90% and a lifetime of more than 2,000?h at 1?A?cm?2 for high-temperature CO2-to-CO conversion at 800?°C. Its selectivity towards CO is about 100%, and its single-pass yield reaches 90%. We show that the efficacy of our catalyst arises from its unique encapsulated structure and optimized alloy composition, which simultaneously enable enhanced CO2 adsorption, moderate CO adsorption and suppressed metal agglomeration. This work provides an efficient strategy for the design of catalysts for high-temperature reactions that overcomes the typical trade-off between activity and stability and has potential industrial applications.
地球科學Earth Science
End-to-end data-driven weather prediction
端到端數據驅動的天氣預報
▲ 作者：Anna Allen, Stratis Markou, Will Tebbutt, James Requeima, Wessel P. Bruinsma, Tom R. Andersson, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-08897-0
▲摘要：
天氣預報對包括交通、農業、工業以及公眾安全的一系列人類活動至關重要。機器學習通過用神經網絡取代數值求解器來變革數值天氣預報（NWP），提高了預測通道中預報組件的速度和準確性。然而，當前模型在初始化時依賴于數值系統并產生局部預報，從而限制了其可實現的收益。
研究組展示了單個機器學習模型可取代整個NWP通道。Aardvark Weather是一個端到端數據驅動的天氣預報系統，它攝取觀測數據并生成全球網格化預報和本地站點預報。在幾個變量和提前期方面，全球預測的表現優于運營NWP基線。當地氣象站的預報在長達十天的提前期內都很熟練，可媲美后處理的全球NWP基線以及由人類預報員輸入的最先進的端到端預報系統。端到端調優進一步提高了本地預測的準確性。
該研究結果表明，在部署時不依賴NWP，也可以進行熟練的預測，這實現了數據驅動模型的全部速度優勢和準確性優勢。研究組希冀，Aardvark Weather將成為新一代端到端模型的起點，這將大幅降低計算成本，并為一系列終端用戶快速、經濟地創建定制模型。
▲ Abstract：
Weather prediction is critical for a range of human activities, including transportation, agriculture and industry, as well as for the safety of the general public. Machine learning transforms numerical weather prediction (NWP) by replacing the numerical solver with neural networks, improving the speed and accuracy of the forecasting component of the prediction pipeline. However, current models rely on numerical systems at initialization and to produce local forecasts, thereby limiting their achievable gains. Here we show that a single machine learning model can replace the entire NWP pipeline. Aardvark Weather, an end-to-end data-driven weather prediction system, ingests observations and produces global gridded forecasts and local station forecasts. The global forecasts outperform an operational NWP baseline for several variables and lead times. The local station forecasts are skilful for up to ten days of lead time, competing with a post-processed global NWP baseline and a state-of-the-art end-to-end forecasting system with input from human forecasters. End-to-end tuning further improves the accuracy of local forecasts. Our results show that skilful forecasting is possible without relying on NWP at deployment time, which will enable the realization of the full speed and accuracy benefits of data-driven models. We believe that Aardvark Weather will be the starting point for a new generation of end-to-end models that will reduce computational costs by orders of magnitude and enable the rapid, affordable creation of customized models for a range of end users.
A foundation model for the Earth system
一種地球系統的基礎模型
▲ 作者：Cristian Bodnar, Wessel P. Bruinsma, Ana Lucic, Megan Stanley, Anna Allen, Johannes Brandstetter, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-09005-y
▲摘要：
可靠預測地球系統對于減輕自然災害和支持人類進步至關重要。傳統的數值模型雖然功能強大，但計算成本極高。人工智能（AI）的最新進展在提高預測性能和效率方面頗有前景，但AI在諸多地球系統領域的應用潛力尚未得到充分開發。
研究組介紹了Aurora，這是一個基于一百多萬小時多樣化地球物理數據訓練的大規模基礎模型。Aurora在預測空氣質量、海浪、熱帶氣旋路徑和高分辨率天氣方面均優于業務預測，計算成本大幅降低。
由于能夠以適中的成本對各種應用場景進行微調，Aurora代表了向精準高效的地球系統預測大眾化邁出的重要一步。這些結果凸顯了AI在環境預測方面的變革潛力，并為更廣泛地獲取高質量氣候和天氣信息鋪平了道路。
▲ Abstract：
Reliable forecasting of the Earth system is essential for mitigating natural disasters and supporting human progress. Traditional numerical models, although powerful, are extremely computationally expensive. Recent advances in artificial intelligence (AI) have shown promise in improving both predictive performance and efficiency, yet their potential remains underexplored in many Earth system domains. Here we introduce Aurora, a large-scale foundation model trained on more than one million hours of diverse geophysical data. Aurora outperforms operational forecasts in predicting air quality, ocean waves, tropical cyclone tracks and high-resolution weather, all at orders of magnitude lower computational cost. With the ability to be fine-tuned for diverse applications at modest expense, Aurora represents a notable step towards democratizing accurate and efficient Earth system predictions. These results highlight the transformative potential of AI in environmental forecasting and pave the way for broader accessibility to high-quality climate and weather information.
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