The K2-OjOS Project*New and revisited planets and candidates in K2 campaigns 5, 16, & 18
Journal article, 2022

We present the first results of K2-OjOS, a collaborative project between professional and amateur astronomers primarily aimed to detect, characterize, and validate new extrasolar planets. For this work, 10 amateur astronomers looked for planetary signals by visually inspecting the 20 427 light curves of K2 campaign 18 (C18). They found 42 planet candidates, of which 18 are new detections and 24 had been detected in the overlapping C5 by previous works. We used archival photometric and spectroscopic observations, as well as new high-spatial resolution images in order to carry out a complete analysis of the candidates found, including a homogeneous characterization of the host stars, transit modelling, search for transit timing variations and statistical validation. As a result, we report four new planets (K2-355 b, K2-356 b, K2-357 b, and K2-358 b) and 14 planet candidates. Besides, we refine the transit ephemeris of the previously published planets and candidates by modelling C5, C16 (when available) and C18 photometric data jointly, largely improving the period and mid-transit time precision. Regarding individual systems, we highlight the new planet K2-356 b and candidate EPIC 211537087.02 being near a 2:1 period commensurability, the detection of significant TTVs in the bright star K2-184 (V = 10.35), the location of K2-103 b inside the habitable zone according to optimistic models, the detection of a new single transit in the known system K2-274, and the disposition reassignment of K2-120 b, which we consider as a planet candidate as the origin of the signal cannot be ascertained.

photometric

detection

fundamental parameters

fundamental parameters

techniques

planets and satellites

image processing

stars

techniques

planets and satellites

Author

A. Castro-González

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

E. Díez Alonso

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

J. Menéndez Blanco

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

J. Livingston

University of Tokyo

Jerome P. De Leon

University of Tokyo

J. Lillo-Box

Centro de Astrobiologia (CAB)

Judith Korth

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics, Astronomy and plasmaphysics 2

S. Fernández Menéndez

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

J. M. Recio

University of Oviedo

Fernando Izquierdo Ruiz

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry

A. Coya Lozano

Sociedad Astronómica Asturiana Omega

F. García De La Cuesta

Sociedad Astronómica Asturiana Omega

N. Gómez Hernández

Sociedad Astronómica Asturiana Omega

J. R. Vidal Blanco

Sociedad Astronómica Asturiana Omega

R. Hevia Díaz

Sociedad Astronómica Asturiana Omega

R. Pardo Silva

Sociedad Astronómica Asturiana Omega

S. Pérez Acevedo

Sociedad Astronómica Asturiana Omega

J. Polancos Ruiz

Sociedad Astronómica Asturiana Omega

P. Padilla Tijerín

Sociedad Astronómica Asturiana Omega

D. Vázquez García

Sociedad Astronómica Asturiana Omega

S. L. Suárez Gómez

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

F. García Riesgo

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

C. González Gutiérrez

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

L. Bonavera

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

J. González-Nuevo

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

C. Rodríguez Pereira

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

F. Sánchez Lasheras

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

M. L. Sánchez Rodríguez

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

R. Muñiz

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

J. D. Santos Rodríguez

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

F. J. De Cos Juez

Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)

Monthly Notices of the Royal Astronomical Society

0035-8711 (ISSN) 1365-2966 (eISSN)

Vol. 509 1 1075-1095

Subject Categories

Astronomy, Astrophysics and Cosmology

Atom and Molecular Physics and Optics

Signal Processing

DOI

10.1093/mnras/stab2669

More information

Latest update

1/4/2022 1