The Gaia Data Release 3 (DR3) contains reflectance spectra at visible wavelengths for 60,518 asteroids over the range between 374-1034 nm, representing a large sample that is well suited to studies of asteroid families. We want to assess the potential of Gaia spectra in identifying asteroid family members. Here, we focus on two L-type families, namely Tirela/Klumpkea and Watsonia. These families are known for their connection to Barbarian asteroids, which are potentially abundant in calcium-aluminum rich inclusions (CAIs). Our method is based (1) on a color taxonomy specifically built on Gaia data and (2) the similarity of spectra of candidate members with the template spectrum of a specific family. We identified objects in the halo of Tirela/Klumpkea, along with possible interlopers. We also found an independent group of eight asteroids erroneously linked to the family by the hierarchical clustering method (HCM). Consequently, the knowledge of the size distribution of the family has been significantly improved, with a more consistent shape at the larger end. The Watsonia family is a more intricate case, mainly due to its smaller size and the less marked difference between the spectral types of the background and of the family members. However, the spectral selection helps identify objects that were not seen by HCM, including a cluster separated from the family core by a resonance. For both families, the V-shape is better defined, leading to a revised age estimation based on the memberships established mainly from spectral properties. Our work demonstrates the advantage of combining the classical HCM approach to spectral properties obtained by Gaia for the study of asteroid families. Future data releases are expected to further expand the capabilities in this domain
Gaia DR3 supervised classification of asteroid reflectance spectra
Université Côte d’Azur, CNRS-Lagrange, Observatoire de la Côte d’Azur(蔚蓝海岸大学,CNRS-拉格朗日实验室,蔚蓝海岸天文台);University of Leicester, School of Physics and Astronomy(莱斯特大学,物理与天文学学院);University of Leicester, School of Natural Sciences(莱斯特大学,自然科学学院)
Taxonomy of 14042 asteroids from Gaia DR3 reflectance spectra
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);INAF-IAPS, Institute for Space Astrophysics and Planetology(意大利国家天体物理研究所空间天体物理学和行星学研究所);Université Marie et Louis Pasteur, CNRS, Institut UTINAM (UMR 6213), équipe Astro(玛丽·路易·巴斯德大学、法国国家科学研究中心、UTINAM研究所)
UV to far-IR reflectance spectra of carbonaceous chondrites. I. Implications for remote characterization of dark primitive asteroids targeted by sample-return missions
2004 EW95: A phyllosilicate bearing carbonaceous asteroid in the Kuiper Belt
太阳系动力学演化的模型预测,由于行星迁移的早期阶段,原始微行星会从它们的形成区域分散到气态巨行星中。因此,碳质物体散布到外部小行星带和柯伊伯带。这些模型预测柯伊伯带应该包含一小部分具有碳质表面的天体,尽管迄今为止,所有报道的小型柯伊伯带天体(KBO)的可见光反射光谱都是线性和无特征的。我们报告了一个小的KBO,(120216)2004 EW 95的不寻常的反射光谱,表现出其近紫外反射率的大幅下降和广泛的浅光学吸收功能中心在约700 nm,这是检测到大于4西格玛的意义。这些特征,通过光谱光度学和光谱学的多个时代证实,分别与氧化铁和层状硅酸盐有关。光谱与一些C-型小行星的光谱有着惊人的相似之处,这表明2004 EW 95可能与这些天体有着共同的起源。2004 EW 95以相对较高的偏心率和倾角与海王星稳定的平均运动共振轨道围绕太阳运行,这表明它可能是由于过去的动力学不稳定性而被安置在那里的。这些结果似乎与上述模型预测一致,并且是第一个显示在小KBO上可靠确认的硅酸盐材料检测的结果。
Near-ultraviolet to visible spectroscopy of the Themis and Polana-Eulalia complex families
目的。我们研究的目的是获得原始小行星的近紫外到可见光(NUV-VIS,0.35 - 0.95微米)反射光谱,重点是Themis和Polana-Eulalia复合体家族的成员。这一特征使我们能够讨论两个最近的样本返回任务目标小行星,(162173)Ryugu和(101955)Bennu的起源。方法.我们使用位于Roque de los Muchachos天文台的望远镜获得了目标小行星低至0.35微米的低分辨率可见光谱,并重新审视了已经发表的光谱数据。我们研究了原始小行星的NUV-VIS反射光谱的特征,重点是Themis家族和Polana-Eulalia家族复合体的数据。最后,我们比较了这些家庭的NUV特性与(162173)Ryugu和(101955)Bennu。在这项工作中,我们还研究了系统的影响,由于使用五个常用的恒星在兰道尔特的目录作为太阳类似物,以获得小行星的反射率在NUV波长范围。我们比较了五个G-恒星的光谱在兰道尔特的目录与光谱的充分研究的太阳模拟毕宿64,也观察到在同一个夜晚。结果我们发现,许多广泛使用的Landolt的G-型恒星在NUV波长光谱区不是太阳类似物,因此不适合获得小行星的反射光谱。我们还发现,即使忒弥斯家族和Polana-Eulalia家族复合体在可见光波长下显示出类似的蓝色,但忒弥斯家族的NUV吸收比Polana-Eulalia家族复合体深得多。我们没有发…
Physical properties of B-type asteroids from WISE data
目的:我们的目标是获得更多的信息,B型小行星的物理性质,并通过研究他们的物理特性,从拟合小行星热模型,以他们的美国宇航局的广域红外巡天探测器(WISE)的数据扩展到以前的工作。我们还研究了帕拉斯碰撞的家庭,一个B型家庭与一个中等高的crackdo的对比,绝大多数的B型。研究方法:我们将NEATM和反射太阳光模型相结合应用于WISE小行星数据,以导出有效直径(D)、所谓的红外辐射参数(η)、红外辐射与可见辐射的比值(R_p = p_{IR} /p_V)和可见几何辐射(p_V)。结果如下:我们获得了$\ga$ 100颗B型小行星的参数值,并绘制了p_V、R_p和η的值分布图(p_V = 0.07 ± 0.03 $, R_p = 1.0 +- 0.2, and η= 1.0 +- 0.1). By combining the IR and visible albedos with 2.5-micron reflectances from the literature we obtained the ratio of reflectances at 3.4 and 2.5 micron, from which we found statistically significant indications that the presence of a 3-micron absorption b…
Infrared-to-visible albedo ratio of Phobos: Comparison with primitive asteroids
Université Côte d’Azur(蔚蓝海岸大学);CNRS–Lagrange(法国国家科学研究中心-拉格朗日实验室);Observatoire de la Côte d’Azur(蔚蓝海岸天文台);Centre national d’études spatiales (CNES)(法国国家空间研究中心);Istituto Nazionale di Astrofisica (INAF) – Osservatorio Astronomico di Padova (OAPd)(意大利国家天体物理研究所帕多瓦天文台);University of Leicester(莱斯特大学)
Development of a multispectral stereo-camera system comparable to Hayabusa2 Optical Navigation Camera (ONC-T) for observing samples returned from asteroid (162173) Ryugu
隼鸟2号从小行星(162173)Ryugu收集了5.4克样本,并将其带回地球。获得这些样品的多波段图像,其光谱波段与遥感观测所用的光谱波段相当,这对于确定所收集样品的特征和研究样品与整个Ryugu航天器观测结果相比的代表性非常重要。在这项研究中,我们构建了一个多波段显微相机系统,使视觉多光谱成像在390(ul),475(b),550(v),590(Na),700(w),和850 nm(x),和三维(3D)形状重建的单个颗粒样品的立体成像的基础上。成像系统产生4096 x 2160像素的图像,像素分辨率为1.93 μm/pix,视场为7.9 x 4.2 mm。我们的验证测量表明,我们的多光谱成像系统,观察样品的光谱波段与隼鸟2号望远镜光学导航相机(ONC-T)上的光谱波段相当,产生具有3%的相对误差的反射光谱和具有5%的误差的3D模型。这些结果表明,具有三维形状重建能力的多波段成像系统在返回的样品上产生准确的光谱和形状数据。使用该仪器,我们对从小行星上的两个位置获得的两个Ryugu样本(A3和C1盘中的颗粒)进行了多光谱测量。测得的Ryugu样品的平均光谱是平坦的,与Ryugu的全球平均光谱一致。在550 nm波段(v波段)的反射率平均为2.4%,高于用ONC-T观测到的Ryugu的全球平均光谱。这种明显的差异可能是因为返回的颗粒具有更大的镜面反射率。
Tianwen-2 target asteroid (469219) Kamo'oalewa probably develops an Itokawa-compositional but ultra-highly space-weathered surface
Center for Lunar and Planetary Sciences, Institute of Geochemistry, Chinese Academy of Sciences(中国科学院地球化学研究所);State Key Laboratory of Lunar and Planetary Sciences, Macau University of Science and Technology(澳门科技大学);School of Earth Sciences, China University of Geosciences(中国地质大学);Department of Physics, University of Helsinki(赫尔辛基大学);Asteroid Engineering Laboratory, LuleåUniversity of Technology(鲁勒技术大学);Institute of applied physics "Nello Carrara", Sesto Fiorentino(内洛·卡拉拉应用物理研究所);Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences(中国科学院紫金山天文台);Department of Earth and Planetary Science, The University of Tokyo(东京大学);Aix Marseille Université, CNRS, CNES, Laboratoire d’Astrophysique de Marseille(马赛大学);Department of Geological Sciences, Brown University(布朗大学);Department of Geography, University of Winnipeg(温尼伯大学);Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology(麻省理工学院);UJF-Grenoble 1/CNRS-INSU, Institut de Planétologie et d'Astrophysique de Grenoble(格勒诺布尔行星与天体物理研究所);Institute of Astronomy, National Central University(中央大学);ESA ESRIN/PDO/NEO Coordination Centre(欧洲航天局地球观测中心近地天体协调中心);Elecnor Deimos(埃莱科诺尔戴莫斯);School of Engineering, Guangzhou College of Technology and Business(广州工商学院);European Southern Observatory (ESO)(欧洲南方天文台);Chongqing University State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Institute of Systems Engineering(重庆大学);Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, School of Space Science and Physics, Institute of Space Sciences, Shandong University(山东大学)
Near-mid infrared spectroscopy of carbonaceous chondrites: Insights into spectral variation due to aqueous alteration and thermal metamorphism in asteroids
Composition and Space Weathering Characteristics of Tianwen-2 Mission's First Target Near-Earth Asteroid (469219) Kamo`oalewa
National Space Science Center, Chinese Academy of Sciences(中国科学院国家空间科学中心);University of Chinese Academy of Science(中国科学院大学);Sun Yat-sen University(中山大学);Xinjiang Astronomical Observatory, Chinese Academy of Sciences(中国科学院新疆天文台);Shandong University(山东大学)