Title
Photometric survey of 55 near-earth asteroids
Date Issued
01 December 2021
Access level
open access
Resource Type
journal article
Author(s)
Hromakina T.
Birlan M.
Barucci M.A.
Fulchignoni M.
Fornasier S.
Merlin F.
Sonka A.
Petrescu E.
Perna D.
Dotto E.
Université de Paris
Publisher(s)
EDP Sciences
Abstract
Context. Near-earth objects (NEOs), thanks to their proximity, provide a unique opportunity to investigate asteroids with diameters down to dozens of meters. The study of NEOs is also important because of their potential hazard to the Earth. The investigation of small NEOs is challenging from Earth as they are observable only for a short time following their discovery and can sometimes only be reached again years or decades later. Aims. We aim to derive the visible colors of NEOs and perform an initial taxonomic classification with a main focus on smaller objects and recent discoveries. Methods. Photometric observations were performed using the 1.2m telescope at the Haute-Provence observatory and the 1.0m telescope at the Pic du Midi observatory in broadband Johnson-Cousins and Sloan photometric systems. Results. We present new photometric observations for 55 NEOs. Our taxonomic classification shows that almost half (43%) of the objects in our sample are classified as S+Q-complex members, 19% as X-complex, 16% as C-complex, 12% as D-types, and finally 6% and 4% as A-and V-types, respectively. The distribution of the observed objects with H > 19 and H ≤ 19 remains almost the same. However, the majority of the objects in our dataset with D < 500 m belong to the "silicate"group, which is probably a result of an observational bias towards brighter and more accessible objects. "Carbonaceous"objects are predominant among those with a Jovian Tisserand parameter of Tj < 3. These bodies could be dormant or extinct comets. The median values of the absolute magnitude for "carbonaceous"and "silicate"groups are H = 18.10 ± 0:95 and H = 19:50 ± 1:20, whereas the estimated median diameters are D= 1219 ± 729 m and D= 344 ± 226 m, respectively. "Silicate"objects have a much lower median Earth's minimum orbit intersection distance (MOID) and a somewhat lower orbital inclination in comparison to "carbonaceous"objects. About half of the observed objects are potentially hazardous asteroids and are mostly (almost 65%) represented by "silicate"objects.
Volume
656
Language
English
OCDE Knowledge area
Astronomía
Subjects
Scopus EID
2-s2.0-85121247100
Source
Astronomy and Astrophysics
ISSN of the container
00046361
Sponsor(s)
The difficulty in studying the smallest NEOs comes from their faintness, which results in a rather small observability window (Birlan et al. 2015). Therefore, a dedicated rapid-response campaign is needed. The portion of discovered NEOs with known physical properties remains very low: only 20% of the whole population (almost 26 000 objects as of June 2021), and nearly 30% if including only objects larger than 1 km (Perna et al. 2018). The NEOROCKS (NEO Rapid Observation, Characterization, and Key Simulations) project funded by the European Union Horizon 2020 program has been put in place to improve our knowledge of the physical properties of NEOs in the era of a constantly increasing discovery rate of new objects, as well as to address the ever-existing problem of planetary defence.
Sources of information:
Directorio de Producción Científica
Scopus