The trans-Neptunian object (84922) 2003 VS2 through stellar occultations
Gustavo Benedetti-Rossi, P. Santos-Sanz, J. L. Ortiz, M. Assafin, B. Sicardy, N. Morales, R. Vieira-Martins, R. Duffard, F. Braga-Ribas, F. L. Rommel, J. I. B. … 展开作者
Gustavo Benedetti-Rossi, P. Santos-Sanz, J. L. Ortiz, M. Assafin, B. Sicardy, N. Morales, R. Vieira-Martins, R. Duffard, F. Braga-Ribas, F. L. Rommel, J. I. B. Camargo, J. Desmars, A. F. Colas, F. Vachier, Alvarez-Candal, E. Fernández-Valenzuela, L. Almenares, R. Artola, T. -P. Baum, R. Behrend, D. Bérard, F. Bianco, N. Brosch, A. Ceretta, C. A. Colazo, A. R. Gomes-Junior, V. D. Ivanov, E. Jehin, S. Kaspi, J. Lecacheux, A. Maury, R. Melia, S. Moindrot, B. Morgado, C. Opitom, A. Peyrot, J. Pollock, A. Pratt, S. Roland, J. Spagnotto, G. Tancredi, J. -P. Teng, P. Cacella, M. Emilio, F. Feys, R. Gil-Hutton, C. Jacques, D. I. Machado, M. Malacarne, I. Manulis, A. C. Milone, G. Rojas, R. Sfair
We present results from three world-wide campaigns that resulted in the detections of two single-chord and one multi-chord stellar occultations by the Plutino object (84922) 2003~VS$_2$. From the single-chord occultations in 2013 and 2014 we obtained accurate astrometric positions for the object, while from the multi-chord occultation on November 7th, 2014, we obtained the parameters of the best-fitting ellipse to the limb of the body at the time of occultation. We also obtained short-term photometry data for the body in order to derive its rotational phase during the occultation. The rotational light curve present a peak-to-peak amplitude of 0.141 $\pm$ 0.009 mag. This allows us to reconstruct the three-dimensional shape of the body, with principal semi-axes $a = 313.8 \pm 7.1$ km, $b = 265.5^{+8.8}_{-9.8}$ km, and $c = 247.3^{+26.6}_{-43.6}$ km, which is not consistent with a Jacobi triaxial equilibrium figure. The derived spherical volume equivalent diameter of $548.3 ^{+29.5}_{-44.6}$ km is about 5\% larger than the radiometric diameter of 2003~VS$_2$ derived from Herschel data of $523 \pm 35$ km, but still compatible with it within error bars. From those results we can also derive the geometric albedo ($0.123 ^{+0.015}_{-0.014}$) and, under the assumption that the object is a Maclaurin spheroid, the density $ρ= 1400^{+1000}_{-300}$ for the plutino. The disappearances and reappearances of the star during the occultations do not show any compelling evidence for a global atmosphere considering a pressure upper limit of about 1 microbar for a pure nitrogen atmosphere, nor secondary features (e.g. rings or satellite) around the main body.
Understanding the trans-Neptunian Solar system: Reconciling the results of serendipitous stellar occultations and the inferences from the cratering record
The trans-Neptunian object (119951) 2002 KX14 revealed via multiple stellar occultations
Instituto de Astrofísica de Andalucía – Consejo Superior de Investigaciones Científicas (IAA-CSIC)（安达卢西亚天体物理研究所 - 西班牙国家研究委员会）；Florida Space Institute（佛罗里达空间研究所）；Federal University of Technology - Paraná (UTFPR/PPGFA)（巴拉那联邦技术大学）；Laboratório Interinstitucional de e-Astronomia (LIneA/INCT do e-Universo)（跨机构电子天文学实验室）；Observatoire de Paris, Université PSL, Sorbonne Université, Université de Lille, LNE,CNRS（巴黎天文台，PSL大学，索邦大学，里尔大学，法国国家科学研究中心）
Probing close-in satellites of Trans-Neptunian Objects through thermal and direct size measurements
Instituto de Astrofísica de Andalucía, IAA-CSIC（安达卢西亚天体物理研究所）；Deutsches Zentrum für Astrophysik (DZA)（德国天体物理学中心）；Max-Planck-Institut für extraterrestrische Physik（马克斯·普朗克地外物理学研究所）
A multi-chord stellar occultation by the large trans-Neptunian object (174567) Varda
我们介绍了2018年9月10日$^{\rm th}$观测到的大型海王星外天体（174567）Varda的第一次恒星掩星记录的结果。瓦尔达星属于高倾角动力激发星族，它的卫星Ilmarë只有瓦尔达星的一半大小。我们确定Varda的大小和宽度，并约束其3D形状和密度。美国有13个不同的观测点监测了这一事件，其中5个观测点发现了主体的掩星。一个最适合掩星弦的椭圆提供了天体的瞬时边缘，由此计算出几何上的角速度。瓦尔达的大小和形状进行评估，其体积密度的约束，使用瓦尔达的质量已知从以前的作品。最佳拟合椭圆边的半长（赤道）轴为$(383 \pm 3)$ km，视扁率$0.066\pm0.047$对应于视面积等效半径$R'_{\rm equiv}= (370\pm7)$ km，几何扁率为$p_v=0.099\pm 0.002 $，假设绝对视星等为$H_V=3.81\pm0.01$。利用三种可能的自转周期（4.76h、5.91h和7.87h），我们得到了相应的MacLaurin解。此外，鉴于上述周期的单峰旋转光变曲线的低振幅（$0.06\pm0.01$）mag，我们考虑双周期。对于5.91 h周期（最可几周期）及其两倍周期（11.82 h），我们求出了$ρ=(1.78\pm0.06)$ g cm $^{-3}$，$ε=0.235\pm0.050$和$ρ=(1.23\pm0.04)$ g cm $^{-…
Predictions of Stellar Occultations by Haumea and the Event of 4 May 2026
Instituto de Astrofísica de Andalucía-CSIC（安达卢西亚天体物理研究所）；I.E.S Politécnico Hermenegildo Lanz（埃尔梅内吉尔多·兰茨理工学院）；NASA Ames Research Center（美国国家航空航天局艾姆斯研究中心）；Department of Space Sciences and Technologies, Faculty of Science, Akdeniz University（安塔利亚大学理学院空间科学与技术系）；Deutsches Zentrum für Astrophysik (DZA)（德国天体物理学中心）
Instituto de Astrofísica de Andalucía-CSIC（安达卢西亚天体物理研究所-西班牙国家研究委员会）；Max-Planck-Institut für extraterrestrische Physik (MPE)（马克斯·普朗克地外物理研究所）；LESIA - Observatoire de Paris, CNRS（巴黎天文台LESIA实验室-CNRS）；Department of Physics, University of Helsinki（赫尔辛基大学物理系）
Constraining the size, shape, and albedo of the large Trans-Neptunian Object (28978) Ixion with multi-chord stellar occultations
Instituto de Astrofísica de Andalucía, IAA-CSIC（安达卢西亚天体物理研究所）；LIRA, CNRS UMR8254, Observatoire de Paris（巴黎天文台）；Federal University of Technology – Paraná (PPGFA/UTFPR)（巴拉那联邦技术大学）；Laboratório Interinstitucional de e-Astronomia (LIneA)（跨机构电子天文学实验室）；Observatório Nacional (MCTI)（国家天文台）；LTE, Observatoire de Paris, Université PSL, Sorbonne Université, Université de Lille, LNE, CNRS（巴黎天文台）；Türkiye National Observatories, TUG（土耳其国家天文台）；The Scientific and Technological Research Council of Türkiye (TÜBİTAK)（土耳其科学与技术研究委员会）；naXys, Department of Mathematics, University of Namur（南纳慕尔大学）；Federal University of Rio de Janeiro - Observatory of Valongo（里约热内卢联邦大学瓦隆戈天文台）；Instituto de Física, Universidade Federal de Uberlândia（乌贝兰迪亚联邦大学物理研究所）；UNESP – São Paulo State University, Grupo de Dinâmica Orbital e Planetologia（圣保罗州立大学）；Institut Polytechnique des Sciences Avancées (IPSA)（高级科学理工学院）；Deutsches Zentrum für Astrophysik (DZA)（德国天体物理学中心）；Florida Space Institute, University of Central Florida（中佛罗里达大学佛罗里达太空研究所）；Department of Space Sciences and Technologies, Akdeniz University（安塔利亚大学空间科学与技术系）；Trans-Tasman Occultation Alliance (TTOA)（跨塔斯曼掩食联盟）；Institute of Astronomy and Astrophysics, University of Tübingen（蒂宾根大学天体物理学与天文学研究所）
Size, atmospheric, and ring constraints on the large Kuiper belt object (55565) Aya from a stellar occultation
National Astronomical Observatory of Japan（日本国立天文台）；Ishigakijima Astronomical Observatory, Public Relations Center, National Astronomical Observatory of Japan（日本国立天文台石垣岛天文台公共关系中心）；Department of Physics, Kurume University, School of Medicine（久留米大学医学部物理系）；Institute of Astronomy, Graduate School of Science, The University of Tokyo（东京大学理学研究科天文学研究所）；University of Occupational and Environmental Health, Japan（日本职业环境健康大学）；Planetary Exploration Research Center, Chiba Institute of Technology（千叶工业大学行星探索研究中心）；Saga Hoshizora Astronomy Center（佐贺星空天文中心）；Kyoto Sangyo University, Koyama Space Science Institute（京都产业大学小山宇宙科学研究所）
Investigating the formation of small Solar System objects using stellar occultations by satellites: present, future and its use to update satellite orbits
A stellar occultation by Vanth, a satellite of (90482) Orcus
South African Astronomical Observatory（南非天文台）；Massachusetts Institute of Technology（麻省理工学院）；Lowell Observatory（洛厄尔天文台）；University of Cape Town（开普敦大学）；Universität Stuttgart（斯图加特大学）；Deutsches SOFIA Institut, Universität Stuttgart（德国SOFIA研究所，斯图加特大学）；SOFIA Science Center, NASA Ames Research Center（NASA艾姆斯研究中心SOFIA科学中心）；Las Cumbres Observatory（拉斯坎布雷斯天文台）
