Using AI for Wavefront Estimation with the Rubin Observatory Active Optics System
John Franklin Crenshaw, Andrew J. Connolly, Joshua E. Meyers, J. Bryce Kalmbach, Guillem Megias Homar, Tiago Ribeiro, Krzysztof Suberlak, Sandrine Thomas, Te-wei Tsai
Vera C. Rubin天文台将在10年期间反复勘测南天区。为确保Rubin生成的图像满足精确科学的质量要求，天文台将使用主动光学系统（AOS）来校正由光学系统中的重力和温度梯度引起的对准和镜面扰动。为此，Rubin将利用位于焦平面边缘传感器的离焦图像来学习并校正波前扰动。我们设计了一个深度学习模型用于波前估计，并将其集成到AOS流水线中。在本文中，我们将这种深度学习方法的性能与Rubin的基线算法进行比较，应用于来自Rubin光学系统两种不同模拟的图像。我们表明深度学习方法更快且更准确，对于高质量图像以及具有严重混合和渐晕的低质量图像，均达到了大气误差下限。与基线算法相比，深度学习模型速度快40倍，在理想条件下中值误差好2倍，在存在Rubin相机渐晕时好5倍，在拥挤星场存在混合时好14倍。此外，在AOS闭环模拟中，深度学习模型超过了所需的光学质量。该系统有望将可用于精确科学的勘测面积增加最多8%。我们讨论了在调试和运行Rubin时如何部署该系统。
英文摘要：
The Vera C. Rubin Observatory will, over a period of 10 years, repeatedly survey the southern sky. To ensure that images generated by Rubin meet the quality requirements for precision science, the observatory will use an Active Optics System (AOS) to correct for alignment and mirror surface perturbations introduced by gravity and temperature gradients in the optical system. To accomplish this Rubin will use out-of-focus images from sensors located at the edge of the focal plane to learn and correct for perturbations to the wavefront. We have designed and integrated a deep learning model for wavefront estimation into the AOS pipeline. In this paper, we compare the performance of this deep learning approach to Rubin's baseline algorithm when applied to images from two different simulations of the Rubin optical system. We show the deep learning approach is faster and more accurate, achieving the atmospheric error floor both for high-quality images, and low-quality images with heavy blending and vignetting. Compared to the baseline algorithm, the deep learning model is 40x faster, the median error 2x better under ideal conditions, 5x better in the presence of vignetting by the Rubin camera, and 14x better in the presence of blending in crowded fields. In addition, the deep learning model surpasses the required optical quality in simulations of the AOS closed loop. This system promises to increase the survey area useful for precision science by up to 8%. We discuss how this system might be deployed when commissioning and operating Rubin.
The Vera C. Rubin Observatory Prompt Processing System
University of Washington, Seattle, WA, USA（华盛顿大学）；SLAC National Accelerator Laboratory, Menlo Park, CA, USA（SLAC国家加速器实验室）；Burwood Group, Oak Brook, IL, USA（伯伍德集团）
该研究介绍了Vera C. Rubin Observatory的即时处理系统如何满足高吞吐量、低延迟和高可靠性的要求，并展示了观测站的调试结果。
The limiting temporal resolution of a time-domain survey in detecting transient behavior is set by the time between observations of the same sky area. We analyze the distribution of visit separations for a range of Vera C. Rubin Observatory cadence simulations. Current simulations are strongly peaked at the 22 minute visit pair separation and provide effectively no constraint on temporal evolution within the night. This choice will necessarily prevent Rubin from discovering a wide range of astrophysical phenomena in time to trigger rapid followup. We present a science-agnostic metric to supple…
We investigate a novel satellite avoidance strategy to mitigate the impact of large commercial satellite constellations in low-Earth orbit on the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST). We simulate the orbits of currently planned Starlink and OneWeb constellations ($\sim$40,000 satellites) to test how effectively an upgraded Rubin scheduler algorithm can avoid them, and assess how the overall survey is affected. Given a reasonably accurate satellite orbit forecast, we find it is possible to adjust the scheduler algorithm to effectively avoid some satellites. Overall, …
Laser-based metrology systems vs wavefront sensing techniques: a comparative overview between the Large Binocular Telescope and the Vera C. Rubin Observatory for the telescope alignment and collimation tracking
INAF Osservatorio di Astrofisica e Scienza dello Spazio（意大利国家天体物理研究所空间天体物理与科学观测站）；Vera C. Rubin Observatory Project Office（薇拉·C·鲁宾天文台项目办公室）；California Institute of Technology（加州理工学院）；Wyant College of Optical Sciences, University of Arizona（亚利桑那大学怀安特光学科学学院）；Large Binocular Telescope Observatory, University of Arizona（亚利桑那大学大双筒望远镜天文台）；DIRAC Institute, University of Washington（华盛顿大学迪拉克研究所）；Department of Astronomy, University of Washington（华盛顿大学天文学系）；Department of Physics, Duke University（杜克大学物理学系）；Observatorio Astrofisico di Arcetri（阿尔切特里天体物理观测站）；Vera C. Rubin Observatory（薇拉·C·鲁宾天文台）；Department of Astrophysical Sciences, Princeton University（普林斯顿大学天体物理科学系）；INAF OATS（意大利国家天体物理研究所的奥阿斯特天文台）；INAF IASF（意大利国家天体物理研究所的星际介质和天体物理学研究所）；Department of Physics “E. Pancini”, University Federico II of Napoli（那不勒斯费德里科二世大学“E.潘奇尼”物理学系）；Harvard Physics Department（哈佛大学物理学系）；Vera C Rubin Observatory/NOIRLab（薇拉·C·鲁宾天文台/美国国家光学红外天文实验室）；Department of Physics, Stanford University（斯坦福大学物理学系）；SLAC National Accelerator Laboratory（斯坦福直线加速器中心）
Starting from a description of the Rubin Observatory Data Management System Architecture, and drawing on our experience with and involvement in a range of other projects including Gaia, SDSS, UKIRT, and JCMT, we derive a series of generic design patterns and lessons learned.
The Vera Rubin Observatory, set to begin observations in mid-2024, will increase our discovery rate of supernovae to well over one million annually. There has been a significant push to develop new methodologies to identify, classify and ultimately understand the millions of supernovae discovered with the Rubin Observatory. Here, we present the first simulation-based inference method using normalizing flows, trained to rapidly infer the parameters of toy supernovae model in multivariate, Rubin-like datastreams. We find that our method is well-calibrated compared to traditional inference method…
We report studies on the mitigation of optical effects of bright low-Earth-orbit (LEO) satellites on Vera C. Rubin Observatory and its Legacy Survey of Space and Time (LSST). These include options for pointing the telescope to avoid satellites, laboratory investigations of bright trails on the Rubin Observatory LSST camera sensors, algorithms for correcting image artifacts caused by bright trails, experiments on darkening SpaceX Starlink satellites, and ground-based follow-up observations. The original Starlink v0.9 satellites are g ~ 4.5 mag, and the initial experiment "DarkSat" is g ~ 6.1 ma…
Early Telescope Throughput Results from the Collimated Beam Projector at the Vera C. Rubin Observatory
Laboratoire d’Annecy de Physique des Particules (LAPP)（巴黎-萨克雷大学粒子物理实验室）；NSF’s NOIRLab（美国国家光学红外天文实验室）；SLAC National Accelerator Laboratory（斯坦福直线加速器中心）；Laboratoire Irène Joliot-Curie (IJCLab)（伊雷娜·约里奥-居里实验室）；Kavli Institute for Particle Astrophysics & Cosmology (KIPAC)（卡弗里粒子天体物理与宇宙学研究所）；Department of Physics, Harvard University（哈佛大学物理系）
The Rubin Observatory's Data Butler is designed to allow data file location and file formats to be abstracted away from the people writing the science pipeline algorithms. The Butler works in conjunction with the workflow graph builder to allow pipelines to be constructed from the algorithmic tasks. These pipelines can be executed at scale using object stores and multi-node clusters, or on a laptop using a local file system. The Butler and pipeline system are now in daily use during Rubin construction and early operations.
Vera C. Rubin Observatory is a ground-based astronomical facility under construction, a joint project of the National Science Foundation and the U.S. Department of Energy, designed to conduct a multi-purpose 10-year optical survey of the southern hemisphere sky: the Legacy Survey of Space and Time. Significant flexibility in survey strategy remains within the constraints imposed by the core science goals of probing dark energy and dark matter, cataloging the Solar System, exploring the transient optical sky, and mapping the Milky Way. The survey's massive data throughput will be transformation…
Development of a Retrieval-Augmented Generation Virtual Assistant for Enhanced Information Discovery at Rubin Observatory
NSF-DOE Vera C. Rubin Observatory / NSF NOIRLab（美国国家科学基金会-能源部薇拉·C·鲁宾天文台 / 美国国家光学红外天文研究实验室）；University of Washington（华盛顿大学）；California Institute of Technology（加州理工学院）；D4D CONSULTING LTD.（D4D咨询有限公司）；Swinburne University of Technology（斯威本科技大学）；Australian Astronomical Optics, Macquarie University（澳大利亚天文光学，麦考瑞大学）；Department of Astronomy, Center for Astrophysics, Harvard University（哈佛大学天文学系，天体物理中心）；Center for Astrophysics, Harvard & Smithsonian（哈佛-史密森尼天体物理中心）；Department of Physics, Harvard University（哈佛大学物理系）
The Rubin Observatory Target-of-Opportunity System in the First Year of Operations
University of Zurich（苏黎世大学）；University of Washington（华盛顿大学）；NSF-DOE Vera C. Rubin Observatory / NSF NOIRLab（美国国家科学基金会-能源部薇拉·C·鲁宾天文台/美国国家光学红外天文研究实验室）；Kavli Institute for Particle Astrophysics and Cosmology, Stanford University（斯坦福大学卡弗里粒子天体物理学与宇宙学研究所）；Stanford University（斯坦福大学）；SLAC National Accelerator Laboratory（斯坦福直线加速器中心）；Princeton University（普林斯顿大学）；University of Pittsburgh（匹兹堡大学）；Fermi National Accelerator Laboratory（费米国家加速器实验室）；University of Illinois（伊利诺伊大学）；University of Delaware（特拉华大学）；Joint Space-Science Institute, University of Maryland（马里兰大学联合空间科学研究所）；Aix Marseille Université（艾克斯-马赛大学）；CNRS/IN2P3, CPPM（法国国家科学研究中心/欧洲核子研究组织粒子物理研究所，普罗旺斯粒子与宇宙学物理中心）
We have adapted the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) Science Pipelines to process data from the Gravitational-Wave Optical Transient Observer (GOTO) prototype. In this paper, we describe how we used the Rubin Observatory LSST Science Pipelines to conduct forced photometry measurements on nightly GOTO data. By comparing the photometry measurements of sources taken on multiple nights, we find that the precision of our photometry is typically better than 20~mmag for sources brighter than 16 mag. We also compare our photometry measurements against colour-corrected P…
We present a study of the detection and recovery efficiency of the Rubin Observatory for detached eclipsing binaries (EBs) in the galactic field, globular clusters (GCs) and open clusters (OCs), with a focus on comparing two proposed observing strategies: a standard cadence ("baseline"), and a cadence which samples the galactic plane more evenly ("colossus"). We generate realistic input binary populations in all observing fields of the Rubin Observatory, simulate the expected observations in each filter, and attempt to characterize the EBs using these simulated observations. In our models, we …
High quality, repeatable point-spread functions are important for science cases like direct exoplanet imaging, high-precision astrometry, and high-resolution spectroscopy of exoplanets. For such demanding applications, the initial on-sky point-spread function delivered by the adaptive optics system can require further optimization to correct unsensed static aberrations and calibration biases. We investigated using the Fast and Furious focal-plane wavefront sensing algorithm as a potential solution. This algorithm uses a simple model of the optical system and focal plane information to measure …
Keck Observatory as an HWO Testbed: validating wavefront sensing and control schemes on a large segmented aperture in parallel with high-contrast science
The Vera C. Rubin Observatory will advance many areas of astronomy over the next decade with its unique wide-fast-deep multi-color imaging survey, the Legacy Survey of Space and Time (LSST). The LSST will produce approximately 20TB of raw data per night, which will be automatically processed by the LSST Science Pipelines to generate science-ready data products -- processed images, catalogs and alerts. To ensure that these data products enable transformative science with LSST, stringent requirements have been placed on their quality and scientific fidelity, for example on image quality and dept…
Vera C. Rubin Observatory will be a key facility for small body science in planetary astronomy over the next decade. It will carry out the Legacy Survey of Space and Time (LSST), observing the sky repeatedly in u, g, r, i, z, and y over the course of ten years using a 6.5 m effective diameter telescope with a 9.6 square degree field of view, reaching approximately r = 24.5 mag (5-σ depth) per visit. The resulting dataset will provide extraordinary opportunities for both discovery and characterization of large numbers (10--100 times more than currently known) of small solar system bodies, furth…
We describe Rubin Observatory's experience with offering a data access facility (and associated services including our Science Platform) deployed on Google Cloud infrastructure as part of our pre-Operations Data Preview program.
The presence of fringing in astronomical CCD images will impact photometric quality and measurements. Yet its impact on the Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) has not been fully studied. We present a detailed study on fringing for Charge-Coupled Devices (CCDs) already implemented on the Rubin Observatory LSST Camera's focal plane. After making physical measurements and knowing the compositions, we have developed a model for the e2v CCDs. We present a method to fit for the internal height variation of the epoxy layer within the sensors based on fringing measureme…
Precision wavefront control on future segmented-aperture space telescopes presents significant challenges, particularly in the context of high-contrast exoplanet direct imaging. We present a new wavefront control architecture that translates the ground-based artificial guide star concept to space with a laser source aboard a second spacecraft, formation flying within the telescope field-of-view. We describe the motivating problem of mirror segment motion and develop wavefront sensing requirements as a function of guide star magnitude and segment motion power spectrum. Several sample cases with…
Test Management and Coordination During the Vera C. Rubin Observatory Commissioning and Early Operations Using Zephyr Scale
NSF–DOE Vera C. Rubin Observatory/NSF NOIRLab（美国国家科学基金会-能源部薇拉·C·鲁宾天文台/美国国家光学红外天文实验室）；Department of Physics, University of Wisconsin-Madison（威斯康星大学麦迪逊分校物理系）
Investigation and Mitigation of a Prominent Off-Axis Stray Light Path in Rubin Observatory Commissioning
Fermi National Accelerator Laboratory（费米国家加速器实验室）；University of Chicago（芝加哥大学）；INAF Osservatorio di Astrofisica e Scienza dello Spazio Bologna（意大利国家天体物理研究所博洛尼亚天文与空间科学观测站）；University of Bologna（博洛尼亚大学）；SLAC National Accelerator Laboratory（SLAC国家加速器实验室）；NSF-DOE Vera C. Rubin Observatory / NSF NOIRLab（美国国家科学基金会-能源部维拉·C·鲁宾天文台/美国国家科学基金会NOIR实验室）；Princeton University（普林斯顿大学）；University of Hertfordshire（赫特福德大学）
The Shack-Hartman wavefront sensor designed for final acceptance of 2.5m SAI telescope allows to measure the shape of the wavefront on exit pupil of the telescope using a bright star. The reference laser source on wavelength 532 nm is used for measurements. During testing the device at different telescopes it was found out what it's probable to estimate some properties of air streams in the dome. Such estimations have been made for three domes: 1.5 m AZT-22 and 1.0 m Zeiss telescope of Maidanak Observatory, Uzbekistan and for 2.6 m telescope ZTSh of Crimean observatory, Ukraine. The following …
The commissioning team for the Vera C. Rubin observatory is planning a set of engineering and science verification observations with the Legacy Survey of Space and Time (LSST) commissioning camera and then the Rubin Observatory LSST Camera. The time frame for these observations is not yet fixed, and the commissioning team will have flexibility in selecting fields to observe. In this document, the Dark Energy Science Collaboration (DESC) Commissioning Working Group presents a prioritized list of target fields appropriate for testing various aspects of DESC-relevant science performance, grouped …
Incorporating Wavefront Error, Wavefront Sensing and Control, and Sensitivities into Exposure Time Calculations for Future Space Missions with the Error Budget Software (EBS)
Space Telescope Science Institute（太空望远镜科学研究所）；Jet Propulsion Laboratory, California Institute of Technology（喷气推进实验室，加州理工学院）
The past few decades have seen the burgeoning of wide field, high cadence surveys, the most formidable of which will be the Legacy Survey of Space and Time (LSST) to be conducted by the Vera C. Rubin Observatory. So new is the field of systematic time-domain survey astronomy, however, that major scientific insights will continue to be obtained using smaller, more flexible systems than the LSST. One such example is the Gravitational-wave Optical Transient Observer (GOTO), whose primary science objective is the optical follow-up of Gravitational Wave events. The amount and rate of data productio…
We present the Rubin Observatory system for data storage/retrieval and pipelined code execution. The layer for data storage and retrieval is named the Butler. It consists of a relational database, known as the registry, to keep track of metadata and relations, and a system to manage where the data is located, named the datastore. Together these systems create an abstraction layer that science algorithms can be written against. This abstraction layer manages the complexities of the large data volumes expected and allows algorithms to be written independently, yet be tied together automatically …
Astronomy has entered the multi-messenger data era and Machine Learning has found widespread use in a large variety of applications. The exploitation of synoptic (multi-band and multi-epoch) surveys, like LSST (Legacy Survey of Space and Time), requires an extensive use of automatic methods for data processing and interpretation. With data volumes in the petabyte domain, the discrimination of time-critical information has already exceeded the capabilities of human operators and crowds of scientists have extreme difficulty to manage such amounts of data in multi-dimensional domains. This work i…
The Vera C. Rubin Observatory will increase the number of observed supernovae (SNe) by an order of magnitude; however, it is impossible to spectroscopically confirm the class for all the SNe discovered. Thus, photometric classification is crucial but its accuracy depends on the not-yet-finalized observing strategy of Rubin Observatory's Legacy Survey of Space and Time (LSST). We quantitatively analyze the impact of the LSST observing strategy on SNe classification using simulated multi-band light curves from the Photometric LSST Astronomical Time-Series Classification Challenge (PLAsTiCC). Fir…
Testing of machine learning wavefront sensing algorithms on the Tiny Observatory for Telescope Optimization (TOTO) testbed
Steward Observatory - The University of Arizona（亚利桑那大学斯图尔德天文台）；Wyant College of Optical Sciences - The University of Arizona（亚利桑那大学怀安特光学科学学院）；Department of Physics, University of California, Santa Barbara（加州大学圣塔芭芭拉分校物理系）
Skykatana: a scalable framework to construct sky masks for the Vera Rubin Observatory and large astronomical surveys
Instituto de Ciencias Astronómicas, de la Tierra y del Espacio (ICATE), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)（地球与空间天文科学研究所 (ICATE)，阿根廷国家科学研究委员会 (CONICET)）；Facultad de Ciencias Exactas, Físicas y Naturales (FCEFYN-UNSJ), Universidad Nacional de San Juan（圣胡安国立大学精确、物理与自然科学学院 (FCEFYN-UNSJ)）；Instituto de Astronomía Teórica y Experimental (IATE), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)（理论与实验天文学研究所 (IATE)，阿根廷国家科学研究委员会 (CONICET)）；Observatorio Astronómico Córdoba , Universidad Nacional de Córdoba（科尔多瓦天文台，科尔多瓦国立大学）
Extracting Asteroid Physical Properties from Vera C. Rubin Observatory Science Validation Survey Data: Rotational Periods, Colors, and Taxonomies
São Paulo State University (UNESP)（圣保罗州立大学）；Laboratório Interinstitucional de e-Astronomia（跨机构电子天文实验室）；NSF–DOE Vera C. Rubin Observatory / NSF NOIRLab（美国国家科学基金会-能源部薇拉·C·鲁宾天文台/美国国家科学基金会NOIRLab）；DiRAC Institute and the Department of Astronomy, University of Washington（华盛顿大学天文学系及DiRAC研究所）；Instituto de Astronomía y Ciencias Planetarias, Universidad de Atacama（阿塔卡马大学天文与行星科学研究所）；Universidad Tecnológica del Perú (UTP)（秘鲁理工大学）
PEEPSS: Photonic-Enabled ExoPlanet Spectroscopic Sensor for the Habitable Worlds Observatory
University of Central Florida（中佛罗里达大学）；University of California Santa Cruz（加州大学圣克鲁兹分校）；University of Sydney（悉尼大学）；Space Telescope Science Institute（太空望远镜科学研究所）；Max-Planck-Institut für Astronomie（马克斯·普朗克天文学研究所）
Calibration of MEMS DM actuator gains using a Zernike wavefront sensor on the HiCAT testbed and implications for Habitable Worlds Observatory operations
Space Telescope Science Institute（太空望远镜科学研究所）；Max Planck Institute for Astronomy（马克斯·普朗克天文学研究所）；Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange（蔚蓝海岸大学、蔚蓝海岸天文台、法国国家科学研究中心、拉格朗日实验室）
Ground control to major time-lag: on-sky results of data-driven predictive wavefront control at Keck Observatory
University of California, Santa Cruz（加州大学圣克鲁兹分校）；Wakea Consulting（Wakea咨询公司）；National Research Council Canada - Herzberg（加拿大国家研究委员会-赫茨伯格）；W. M. Keck Observatory（W.M.凯克天文台）；UK Astronomy Technology Centre（英国天体物理技术中心）；University of Hawai’i（夏威夷大学）；Swinburne University of Technology（斯威本科技大学）
Recent work has shown that the correlation between SDSS colors and optical albedo can be used to estimate asteroid sizes from optical data alone. We revisit a correlation between SDSS colors and optical albedo for asteroids, with the albedo derived using WISE-based size estimates. Moeyens, Myhrvold \& Ivezić (2020) showed that this correlation can be used to estimate asteroid sizes with optical data alone, with a precision of about 17\% relative to WISE-based size estimates. We present here several more sophisticated data-driven models for the variation of optical albedo with colors and estima…
The Legacy Survey of Space and Time, operated by the Vera C. Rubin Observatory, is a 10-year astronomical survey due to start operations in 2022 that will image half the sky every three nights. LSST will produce ~20TB of raw data per night which will be calibrated and analyzed in almost real time. Given the volume of LSST data, the traditional subset-download-process paradigm of data reprocessing faces significant challenges. We describe here, the first steps towards a gateway for astronomical science that would enable astronomers to analyze images and catalogs at scale. In this first step we …
The differential Optical Transfer Function (dOTF) is a focal plane wavefront sensing method that uses a diversity in the pupil plane to generate two different focal plane images. The difference of their Fourier transforms recovers the complex amplitude of the pupil down to the spatial scale of the diversity. We produce two simultaneous PSF images with diversity using a polarizing filter at the edge of the telescope pupil, and a polarization camera to simultaneously record the two images. Here we present the first on-sky demonstration of polarization dOTF at the 1.0m South African Astronomical …
We investigate the possibility that a statistical detection of the galaxy parallax shift due to the Earth's motion with respect to the CMB frame (cosmic secular parallax) could be made by the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) or by the Nancy Grace Roman Space Telescope (NGRST), and used to measure the Hubble constant. We make mock galaxy surveys which extend to redshift z=0.06 from a large N-body simulation, and include astrometric errors from the LSST and NGRST science requirements, redshift errors and peculiar velocities. We include spectroscopic redshifts for …
JWST telemetry combined with active coronagraphy: raw contrast predictions for exoplanet imaging with the Habitable Worlds Observatory
Space Telescope Science Institute（太空望远镜科学研究所）；University of California Santa Cruz（加州大学圣克鲁兹分校）；Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange（蔚蓝海岸大学，蔚蓝海岸天文台，法国国家科学研究中心，拉格朗日实验室）；Max Planck Institute for Astronomy（马克斯·普朗克天文学研究所）
