Hazardous asteroid has been one of the concerns for humankind as fallen asteroid on earth could cost a huge impact on the society.Monitoring these objects could help predict future impact events, but such efforts are hindered by the large numbers of objects that pass in the Earth's vicinity. The aim of this project is to use machine learning and deep learning to accurately classify hazardous asteroids. A total of ten methods which consist of five machine learning algorithms and five deep learning models are trained and evaluated to find the suitable model that solves the issue. We experiment on two datasets, one from Kaggle and one we extracted from a web service called NeoWS which is a RESTful web service from NASA that provides information about near earth asteroids, it updates every day. In overall, the model is tested on two datasets with different features to find the most accurate model to perform the classification.
The dynamically hazardous asteroid 2025 TV$_{10}$. A new co-orbital asteroid of Venus
São Paulo State University (UNESP)（圣保罗州立大学）；Laboratório Interinstitucional de e-Astronomia（跨机构电子天文学实验室）；LIRA, Observatoire de Paris, Université PSL, Sorbonne Université, Université Paris Cité, CY Cergy Paris Université, CNRS（LIRA，巴黎天文台，巴黎文理研究大学，索邦大学，巴黎西岱大学，CY塞尔吉巴黎大学，法国国家科学研究中心）
Composition of Potentially Hazardous Asteroid (214869) 2007 PA8: An H Chondrite from the Outer Asteroid Belt
有潜在危险的小行星是在其接近地球期间进行物理特性鉴定的一个独特机会。这些小行星的距离很近，使它们能够进行采样返回和载人飞行任务，但如果发生碰撞，也可能对地球上的生命构成风险。因此，详细的矿物学分析是规划未来勘探任务和制定适当缓解战略的关键组成部分。在这项研究中，我们提出了近红外光谱（0.7-2.55微米）的PHA（214869）2007 PA 8获得与美国宇航局红外望远镜设施在其接近地球的2012年11月。对这颗小行星的矿物学分析显示，其表面成分与普通的H型陨石一致。特别地，我们发现2007 PA 8的橄榄石和辉石化学分别是Fa 18（Fo 82）和Fs 16。橄榄石-辉石丰度比估计为47%。这一低橄榄石丰度和测量的带参数，接近H4和H5方解石，表明2007年PA 8的母体经历了热变质，然后才被灾难性地破坏。根据组成的亲和力，接近J5：2共振，估计通量的共振对象，我们确定的Koronis家庭是最有可能的源区2007年PA 8。
Large potentially hazardous asteroids (PHAs) are capable of causing a global catastrophe in the event of a planetary collision. Thus, rapid assessment of such an object's physical characteristics is crucial for determining its potential risk scale. We treated the near-Earth asteroid (99942) Apophis as a newly discovered object during its 2020-2021 close-approach as part of a mock planetary defense exercise. The object was detected by the Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE), and data collected by the two active bands (3.4 $μ$m and 4.6 $μ$m) were analyzed using therma…
The asteroid 2014 JO25, considered to be "potentially hazardous" by the Minor Planet Center, was spectroscopically followed during its close-Earth encounter on 19th and 20th of April 2017. The spectra of the asteroid were taken with the low resolution spectrograph (LISA), mounted on the 1.2-m telescope at the Mount Abu Infrared Observatory, India. Coming from a region close to the Hungaria population of asteroids, this asteroid follows a comet-like orbit with a relatively high inclination and large eccentricity. Hence, we carried out optical spectroscopic observations of the asteroid to look f…
We present a fireball detected in the night sky over Kyoto, Japan on UT 2017 April 28 at ${\rm 15^{h}\,58^{m}\,19^{s}}$ by the SonotaCo Network. The absolute visual magnitude is $M_{\rm v}$=$-$4.10$\pm$0.42mag. Luminous light curves obtain a meteoroid mass $m$=29$\pm$1g, corresponding to the size $a_{\rm s}$=2.7$\pm$0.1cm. Orbital similarity assessed by D-criterions (cf. $D_{\rm SH}$=0.0079) has identified a likely parent, the binary near-Earth asteroid (164121) 2003 YT$_1$. The suggested binary formation process is a YORP-driven rotational disintegration (Pravec & Harris 2007). The asynchrono…
By means of a fully connected artificial neural network, we identified asteroids with the potential to impact Earth. The resulting instrument, named the Hazardous Object Identifier (HOI), was trained on the basis of an artificial set of known impactors which were generated by launching objects from Earth's surface and integrating them backward in time. HOI was able to identify 95.25% of the known impactors simulated that were present in the test set as potential impactors. In addition, HOI was able to identify 90.99% of the potentially hazardous objects identified by NASA, without being traine…
Asteroid impacts pose a major threat to all life on Earth. The age of the dinosaurs was abruptly ended by a 10-km-diameter asteroid. Currently, a nuclear device is the only means of deflecting large Potentially Hazardous Asteroids (PHAs) away from an Earth-impacting trajectory. The Enhanced Kinetic Impactor (EKI) concept is proposed to deflect large PHAs via maneuvering space rocks. First, an unmanned spacecraft is launched to rendezvous with an intermediate Near-Earth Asteroid (NEA). Then, more than one hundred tons of rocks are collected from the NEA as the EKI. The NEA can also be captured …
Rotation, spectral type, and albedo of the potentially hazardous asteroid (153814) 2001 WN$_{\text 5}$ Prior to the 2028 June close approach
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）；Department of Earth and Planetary Science, The University of Tokyo（东京大学地球行星科学系）；Institute of Astronomy, V.N. Karazin Kharkiv National University（哈尔科夫国立大学瓦·尼·卡拉津天体物理研究所）；Astronomical Institute ASCR（捷克科学院天文研究所）
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency（宇宙科学研究所）；Rowan University（罗文大学）；Lunar and Planetary Laboratory, University of Arizona（亚利桑那大学）；Department of Earth and Planetary Sciences, American Museum of Natural History（美国自然历史博物馆）；The University of Tokyo（东京大学）
Astrometric and Photometric Investigations of 2009 WZ104 Near Earth Asteroid
2009年11月25日，美国亚利桑那州莱蒙山天文台的68厘米施密特卡特琳娜巡天望远镜发现了WZ 104小行星。新物体的观测结果得到了Schiaparelli天文台（意大利）60厘米反射镜和Alter Saltzberg天文台（奥地利维也纳）35厘米施密特-卡塞格伦望远镜的证实。这颗小行星被认为是潜在的危险近地小行星。最小轨道相交距离为0.0304 a.e.。自2009年底以来，普尔科沃天文台（俄罗斯）的MTM-500 M 50厘米弯月望远镜和ZA-320 M 32厘米镜面天体照相机继续对2009 WZ 104小行星进行观测。这些观测是在近地天体调查方案的框架内进行的。为调查确定了以下任务：获得天体测量和测光（BVRI波段）系列观测，根据观测数据改进小行星轨道，确定其分类类别和绝对星等，调查其旋转动力学，估计其物理参数。这颗小行星属于小行星群中的Aten。
Colorado School of Mines（科罗拉多矿业学院）；Institute for Astronomy（天文研究所）
In this paper we present a two-step neural network model to separate detections of solar system objects from optical and electronic artifacts in data obtained with the "Asteroid Terrestrial-impact Last Alert System" (ATLAS), a near-Earth asteroid sky survey system [arXiv:1802.00879]. A convolutional neural network [arXiv:1807.10912] is used to classify small "postage-stamp" images of candidate detections of astronomical sources into eight classes, followed by a multi-layered perceptron that provides a probability that a temporal sequence of four candidate detections represents a real astronomi…
Fifteen orbital clusters (associations) were identified among ~20000 near Earth asteroids (NEAs). All associations were found with a high statistical reliability using a single linkage cluster analysis algorithm and three orbital similarity functions. The identified groups constitute a small fraction (4.74 %) of the entire sample. Nonetheless they may be hazardous to the Earth and its inhabitants. As it happens with meteoroid streams, every year the Earth comes very close to the orbits of each association. In two cases (2008TC3 and 2017FU102) the distance between the asteroid's and the Earth's…
Spin Parameters and Shape Models of Near-Earth Asteroids (4660) Nereus, (21088) Chelyabinsk, (66146) 1998 TU3, and (297418) 2000 SP43
Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA), University of Oviedo（阿斯图里亚斯太空科学与技术大学研究所，奥维耶多大学）；Departamento de Matemáticas, Facultad de Ciencias, Universidad de Oviedo（奥维耶多大学理学院数学系）；Departamento de Informática, Facultad de Ciencias, Universidad de Oviedo（奥维耶多大学理学院计算机系）；Instituto de Astrofísica de Canarias (IAC)（加那利群岛天体物理研究所）；Departamento de Astrofísica, Universidad de La Laguna（拉帕尔马大学天体物理学系）；Light Bridges S. L., Observatorio Astronómico del Teide（光桥有限公司，泰德天文台）；Observatorio Isaac Aznar-MPC Z95（艾萨克·阿兹纳尔小行星中心观测站 Z95）；Departamento de Explotación y Prospección de Minas, Universidad de Oviedo（奥维耶多大学矿产开发与勘探系）
Near-Earth asteroid (410777) 2009 FD is a potentially hazardous asteroid with potential impacts on Earth at the end of the 22nd century. The astrometry collected during the 2019 apparition provides information on the trajectory of (410777) by constraining the Yarkovsky effect, which is the main source of uncertainty for future predictions, and informing the impact hazard assessment. We included the Yarkovsky effect in the force model and estimated its magnitude from the fit to the (410777) optical and radar astrometric data. We performed the (410777) hazard assessment over 200 years by using t…
The surfaces of airless bodies such as asteroids are exposed to many phenomena that can alter their physical properties. Bennu, the target of the OSIRIS-REx mission, has demonstrated how complex the surface of a small body can be. In 2019 November, the potentially hazardous asteroid 2015 JD1 experienced a close approach of 0.0331 au from the Earth. We present results of the physical characterization of 2015 JD1 based on ground-based radar, spectroscopy, and photometric observations acquired during 2019 November. Radar polarimetry measurements from the Arecibo Observatory indicate a morphologic…
Radiolocation methods of probing minor celestial bodies (asteroids) by the nanosecond pulses can be used for monitoring of near-Earth space with the purpose of identification of hazardous cosmic objects able to impact the Earth. Development of the methods that allow to improve accuracy of determining the asteroids size (i.e. whether it measures tens or hundreds meters in diameter) is important for correctly estimating the degree of damage which they can cause (either regional or global catastrophes, respectively). In this paper we suggest a novel method of estimating the sizes of the passive c…
Taxonomic analysis of asteroids with artificial neural networks
Yunnan Observatories, CAS（中国科学院云南天文台）；University of Chinese Academy of Sciences（中国科学院大学）；Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences（中国科学院天体结构与演化重点实验室）；University of Helsinki（赫尔辛基大学）；Deep Space Exploration Laboratory（深空探测实验室）
Thermophysical characterization of the potentially hazardous near-Earth object 2024 YR4
Max-Planck-Institut für extraterrestrische Physik (MPE)（德国马克斯·普朗克地外物理学研究所）；University of Helsinki（赫尔辛基大学）；Massachusetts Institute of Technology（麻省理工学院）；Space Telescope Science Institute（太空望远镜科学研究所）；Johns Hopkins University Applied Physics Laboratory（约翰斯·霍普金斯大学应用物理实验室）；Astronomical Institute, Academy of Sciences of the Czech Republic（捷克科学院天文研究所）；ESA NEO Coordination Centre（欧洲空间局近地天体协调中心）；Jet Propulsion Laboratory, California Institute of Technology（加州理工学院喷气推进实验室）
Thermal Infrared Observations of Asteroid (99942) Apophis with Herschel
小行星阿波菲斯（99942）是一颗具有潜在危险的小行星。我们用赫歇尔空间天文台的PACS仪器在70、100和160微米处对这颗小行星进行了远红外观测。这些照片是在2013年1月和3月的两个时间点，在一次近距离接触地球时拍摄的。这些第一次对阿波菲斯的热测量是在反对派之前和之后以类似的相位角进行的。我们进行了详细的热物理模型分析，通过使用自旋和形状模型最近来自应用2周期傅立叶级数方法，以及校准光度观测的大样本。我们发现，翻滚的小行星阿波菲斯有一个细长的形状，平均直径为375 $^{+14}_{-10}$米（等体积球体）和几何V带的半径为0.30 $^{+0.05}_{-0.06}$。我们发现热惯性在250-800 Jm $^{-2}$ s $^{-0.5}$ K $^{-1}$范围内（最佳解为600 Jm $^{-2}$ s $^{-0.5}$ K $^{-1}$），这可以用低传导性细风化层与表面高热惯性的较大岩石和巨石的混合物来解释。热惯性和其他与（25143）丝川的相似之处表明阿波菲斯可能也有一个碎石堆结构。如果我们结合新的尺寸值与丝川式的密度和孔隙度的假设，我们估计的质量在4.4和6.2 10 $^{10}$公斤，这是超过2-3倍比以前的估计。我们预计，新得出的属性将影响情景研究和影响阿波菲斯的长期轨道预测。
Instituto de Astronomía Teórica y Experimental, CONICET-UNC（CONICET-UNC理论与实验天文研究所）；Instituto de Astrofísica de Andalucía, CSIC（西班牙国家研究委员会安达卢西亚天体物理研究所）；Instituto de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Alicante（阿利坎特大学科学与技术应用物理研究所）；Observatório Nacional/MCTIC（国家天文台（巴西科学、技术、创新和通信部））
We are in an era of large catalogs and, thus, statistical analysis tools for large data sets, such as machine learning, play a fundamental role. One example of such a survey is the Sloan Moving Object Catalog (MOC), which lists the astrometric and photometric information of all moving objects captured by the Sloan field of view. One great advantage of this telescope is represented by its set of five filters, allowing for taxonomic analysis of asteroids by studying their colors. However, until now, the color variation produced by the change of phase angle of the object has not been taken into a…
Surface composition and taxonomic classification of a group of near-Earth and Mars-crossing asteroids
过去，由于缺乏含有矿物学诊断吸收带的高质量近红外光谱数据（0.7-2.5微米），限制近地小行星的表面组成一直很困难。在这里，我们提出了可见光（0.43-0.95微米）和近红外（0.7-2.5微米）光谱的九个近地小行星和五个火星穿越小行星（MC）。所研究的非经济实体是：4055 Magellan，19764（2000 NF 5），89830（2002 CE），138404（2000 HA 24），143381（2003 BC 21），159609（2002 AQ 3），164121（2003 YT 1），241662（2000 KO 44）和2007 ML 13。它们是：1656 Suomi、2577 Litva、5407（1992 AX）、22449 Ottijeff和47035（1998 WS）。这些观测是由智利拉西拉的NTT、西班牙卡拉尔阿尔托的2.2米望远镜和夏威夷莫纳克亚山的IRTF进行的。小行星的分类学分类（Bus系统）表明，所有观测到的MC小行星都属于S-复合体，包括S、Sr和Sl类。其中7个近地小行星属于S复合体，包括S、Sa、Sk和Sl类，2个近地小行星被划为V型。NEA 164121（2003 YT 1）是根据其近红外光谱被分类为V型的，因为这颗小行星没有可见光谱。对其中六颗小行星（已获得或以前可获得近红外光谱的小行星）进行了矿物学分析。我们发现三颗小行星（241…
Composition of Near-Earth Asteroid 2008 EV5: Potential target for Robotic and Human Exploration
我们在可见光（0.30-0.92微米）和近红外（0.75-2.5微米）波长下观察了潜在危险的小行星（PHA）2008 EV 5，以确定其表面成分。这颗小行星特别令人感兴趣，因为它是两个样本返回任务提案（马可波罗-R和隼鸟-2）和人类探索的潜在目标，因为它的低delta-v交会。2008 EV 5的光谱除了一个0.48微米的弱自旋禁戒Fe 3+吸收带外，基本上没有什么特征。光谱也有一个整体的蓝色斜率。2008年EV 5的最大值仍然不确定，根据热模型，下限为0.05，上限为0.20。Busch等人（2011年）估计的0.12与我们的热建模结果一致。2008年EV 5的基因组和组成也与C型分类学分类一致（Somers等人，2008年）。最佳光谱匹配是与类似于Orgueil的Cl碳质方解石，其也具有弱的0.48微米特征和整体蓝色斜率。这个0.48微米的特征也可以在磁铁矿的光谱中看到。CI卫星的最大值是我们对2008年EV 5最大值的估计范围的下限。
We are conducting a survey using twilight time on the Dark Energy Camera with the Blanco 4m telescope in Chile to look for objects interior to Earth's and Venus' orbits. To date we have discovered two rare Atira/Apohele asteroids, 2021 LJ4 and 2021 PH27, which have orbits completely interior to Earth's orbit. We also discovered one new Apollo type Near Earth Object (NEO) that crosses Earth's orbit, 2022 AP7. Two of the discoveries likely have diameters greater than 1 km. 2022 AP7 is likely the largest Potentially Hazardous Asteroid (PHA) discovered in about eight years. To date we have covered…
We aim to determine the distribution of basaltic asteroids (classified as V-types) based on the spectrophotometric data reported in the MOVIS-C catalogue. A total of 782 asteroids were identified. The observations with all four filters (Y, J, H, Ks), available for 297 of these candidates, allow a reliable comparison with the laboratory data of howardite, eucrite, and diogenite meteorites. We found that the majority of the basaltic candidates ($\approx$ 95$\%$) are located in the inner main belt, while only 29 ($\approx$ 4$\%$) and 8 ($\approx$ 1$\%$) are located in the middle and outer main be…
The classification of the minor bodies of the Solar System based on observables has been continuously developed and iterated over the past 40 years. While prior iterations followed either the availability of large observational campaigns or new instrumental capabilities opening new observational dimensions, we see the opportunity to improve primarily upon the established methodology. We developed an iteration of the asteroid taxonomy which allows the classification of partial and complete observations (i.e. visible, near-infrared, and visible-near-infrared spectrometry) and which reintroduces …
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）
