@InProceedings{WinterAraśMaca:2017:ClNETh,
author = "Winter, O. C. and Ara{\'u}jo, R. A. N. and Macau, Elbert Einstein
Nehrer",
affiliation = "{Universidade Estadual Paulista (UNESP)} and {Universidade
Estadual Paulista (UNESP)} and {Instituto Nacional de Pesquisas
Espaciais (INPE)}",
title = "Classification of NEAs through dynamical evolution",
year = "2017",
organization = "Asteroids, Comets, Meteors",
abstract = "Introduction: The near Earth asteroids (NEAs) are usually
classified according to their orbital characteristics into four
groups: Aten, Apollo, Amor and Atira. An Aten has a semi-major
axis of less than 1 au and aphelion distance greater than the
Earth's perihelion distance. An Amor has perihelion distance
greater than the Earth's aphelion distance and aphelion smaller
than 1.3 au. An Apollo has semi-major axis of more than 1 au and
perihelion distance smaller than the Earth's aphelion distance. An
Atira has aphelion distance smaller than Earth's perihelion
distance. However, this is a static classification, based on their
current osculating orbital elements. The NEAs live in a region
highly perturbed by the terrestrial planets. In general, their
lifetime is of the order of 10 Myrs. Most of them cross the border
from one group to another during their lifetime, that means they
temporarily belong to a given group. So, the question is how would
they be classified according to their dynamical orbital evolution?
Approach: In the present work is studied the temporal orbital
evolution of the NEAs. There were performed numerical simulations
of a representative sample of NEAs under the gravitational
influence of all planets and the Sun. Their dynamics is dominated
by the gravitational interactions with the terrestrial planets. A
single close encounter with one of this planets can move an
asteroid from one group to another. We pay special attention to
their mobility as a function of their initial location in the
semi-major axis versus eccentricity plane (a x e), and
consequently in their transition between the groups. Results: A
general view of the results can be seen in Figure 1. T The coded
color indicates the states, i.e, to how many groups a NEA belonged
to along its lifetime. A representative example is the following.
We found two Apollo asteroids with very distinct dynamical
behaviors. One of them explores a wide region of the space
covering all the groups (from the inner Atira up to the outer
Asteroid Main Belt) (Figure 2), while the other asteroid remains
its entire lifetime in a narrow region, jumping from Apollo to
Atens and vice-versa. The results reveal some sort of patterns to
be used in a new classification of the NEAs in terms of dynamical
orbital evolution.",
conference-location = "Montevideo, Uruguay",
conference-year = "10-14 Apr.",
language = "en",
urlaccessdate = "29 mar. 2024"
}