Europlanet Science Congress 2021
Virtual meeting
13 – 24 September 2021
Europlanet Science Congress 2021
Virtual meeting
13 September – 24 September 2021
EPSC Abstracts
Vol. 15, EPSC2021-463, 2021, updated on 15 May 2024
https://doi.org/10.5194/epsc2021-463
Europlanet Science Congress 2021
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

A portrait of the Trans-Neptunian Object (143707) 2003 UY117 from a stellar occultation and photometry data.

Jose L. Ortiz1, Pablo Santos-Sanz1, Bruno Sicardy2, Mónica Vara-Lubiano1, Nicolás Morales1, Estela Fernandez-Valenzuela3, Felipe Braga-Ribas4,5,6, Damya Souami2, Alberto Castro-Tirado1, Emilio Jesús Fernández-García1, Alfredo Sota1, Miguel Sánchez7, Ignacio de la Cueva8, Jose L. Maestre9, Marcel Popescu10, Ana Guijarro11, Emmanuel Jehin12, Francisco J. Pozuelos12, Javier Licandro13, Miguel Rodriguez-Alarcon13, and the 2003UY117 occultation team*
Jose L. Ortiz et al.
  • 1Instituto de Astrofisica de Andalucia-CSIC, Granada, Spain (ortiz@iaa.es)
  • 2LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Paris Diderot, Sorbonne Paris Cité, 5 place JulesJanssen, 92195 Meudon, France.
  • 3Florida Space Institute, University of Central Florida, Orlando, FL 32826- 0650, USA
  • 4Observatório Nacional/MCTIC, R. General José Cristino 77, Bairro Imperial de São Cristóvão, Rio de Janeiro (RJ), Brazil
  • 5Laboratório Interinstitucional de e-Astronomia - LIneA & INCTdo e-Universo, Rua Gal. José Cristino 77, Bairro Imperial de São Cristóvão, Rio de Janeiro (RJ), Brazil
  • 6Federal University of Technology - Paraná (UTFPR/DAFIS), Rua Sete de Setembro, 3165, Curitiba (PR), Brazil
  • 7Sociedad Astronómica Granadina, Granada, Spain
  • 8Astroimagen, Abad y Sierra 58Bis, 07800 Ibiza, Spain
  • 9Observatorio Astronómico de Albox, Apt. 63, E-04800 Albox, Almeria, Spain
  • 10Astronomical Institute of the Romanian Academy, 5 Cut¸itul de Argint, 040557 Bucharest, Romania
  • 11Centro Astronomico Hispano Aleman, Observatorio de Calar Alto, Sierra de los Filabres sn , 04550 Gergal, Almeria, Spain
  • 12University of Liège, Belgium
  • 13Instituto de Astrofísica de Canarias (IAC), C/Vía Láctea s/n, 38205 La Laguna, Tenerife, Spain
  • *A full list of authors appears at the end of the abstract

Within the Lucky Star international collaboration* on stellar occultations by TNOs and other outer solar system bodies, we predicted the occultation by the TNO (143707) 2003 UY117 of an mV ~ 14.6 mag star on 23 October 2020. Around a week before the occultation date, we updated and refined the prediction using high precision astrometry obtained using the 2 m Liverpool telescope located at El Roque de Los Muchachos Observatory on La Palma, Spain. The update resulted in a shadow path with good observability potential. We carried out a specific campaign involving 27 observing sites in the south of Spain and North of Africa to observe the occultation. We recorded 4 positive detections and several very close misses to the south of the body. With this information we determined the silhouette of 2003 UY117 at the moment of the occultation. We also obtained the geometric albedo and the size for this object. In addition to this, we carried out several photometric runs with large telescopes to determine the rotation period and rotational phase at the time of the occultation. The body presents a clear double-peaked rotational light curve consistent with a triaxial ellipsoid of considerable elongation, which means that a rotational light curve analysis is critical to correctly interpret the occultation results. The preliminary analysis indicates a larger equivalent diameter than that determined from Herschel thermal data, although consistent within the large error bars of the thermal determination. We will present the preliminary results and discuss their implications.

*Lucky Star (LS) is an EU-funded research activity to obtain physical properties of distant Solar System objects using stellar occultations. LS collaboration agglomerates the efforts of the Paris, Granada, and Rio teams. https://lesia.obspm.fr/lucky-star/ 

Acknowledgements:

JLO, PS-S, NM, MV, and RD acknowledge financial support from the State Agency for Research of the Spanish MCIU through the ‘Center of Excellence Severo Ochoa’ award for the Instituto de Astrofísica de Andalucía (SEV-2017-0709), they also acknowledge the financial support by the Spanish grant AYA-2017-84637-R and AYARTI2018- 098657-J-I00 ‘LEO-SBNAF’ (MCIU/AEI/FEDER, UE).

2003UY117 occultation team:

R. Vieira-Martins, J. Desmars, R. Duffard, J. Camargo, J. Lecacheux, A. Alvarez-Candal, B. Morgado, M. Kretlow, G. Benedetti-Rossi, J. Marques-Oliveira, F. Rommel, A. R. Gomes-Júnior, R. Boufleur, F. Casarramona, J. J. Castellani, A. Roman, S. Alonso.

How to cite: Ortiz, J. L., Santos-Sanz, P., Sicardy, B., Vara-Lubiano, M., Morales, N., Fernandez-Valenzuela, E., Braga-Ribas, F., Souami, D., Castro-Tirado, A., Fernández-García, E. J., Sota, A., Sánchez, M., de la Cueva, I., Maestre, J. L., Popescu, M., Guijarro, A., Jehin, E., Pozuelos, F. J., Licandro, J., and Rodriguez-Alarcon, M. and the 2003UY117 occultation team: A portrait of the Trans-Neptunian Object (143707) 2003 UY117 from a stellar occultation and photometry data., Europlanet Science Congress 2021, online, 13–24 Sep 2021, EPSC2021-463, https://doi.org/10.5194/epsc2021-463, 2021.