INVESTIGADORES
BRUNINI Adrian
artículos
Título:
Impactor flux and cratering on the Pluto-Charon system
Autor/es:
DE ELÍA, G. C.; DI SISTO, R. P.; BRUNINI, A.
Revista:
ASTRONOMY AND ASTROPHYSICS
Editorial:
EDP SCIENCES S A
Referencias:
Lugar: Paris; Año: 2010 vol. 521 p. 23 - 33
ISSN:
0004-6361
Resumen:
Aims: We study the impactor flux and cratering on Pluto and
Charon caused by the collisional evolution of Plutinos. Plutinos are
trans-Neptunian objects located at ~39.5 AU, in the 3:2 mean motion
resonance with Neptune. <BR /> Methods: We develop a statistical code
that includes catastrophic collisions and cratering events, and takes
into account the stability and instability zones of the 3:2 mean motion
resonance with Neptune. Our numerical algorithm proposes different
initial populations that account for the uncertainty in the size
distribution of Plutinos at small sizes. <BR /> Results: Depending on
the initial population, our results indicate the following. The number
of D > 1 km Plutinos streaking Pluto over 3.5 Gyr is between 1271 and
5552. For Charon, the number of D > 1 km Plutino impactors is between
354 and 1545. The number of D > 1 km craters on Pluto produced by
Plutinos in the past 3.5 Gyr is between 43 076 and 113 879. For Charon,
the number of D > 1 km craters is between 20 351 and 50 688. On the
other hand, the largest Plutino impactor onto Pluto has a diameter of
between ~17 and 23 km, which produces a crater with a diameter of ~31-39
km. In the same way, the largest Plutino impactor onto Charon has a
diameter of between ~10 and 15 km, which produces a crater with a
diameter of ~24-33 km. Finally, we test the dependence of results on the
number of Pluto-sized objects in the Plutino population. If two
Pluto-sized objects are assumed in the 3:2 Neptune resonance, the total
number of Plutino impactors onto both Pluto and Charon with diameters D
> 1 km is a factor of ~1.6-1.8 larger than that obtained considering
only one Pluto-sized object in this resonant region. <BR /> Conclusions:
Given the structure of the trans-Neptunian region, with its dynamically
different populations, it is necessary to study in detail the
contribution of all the potential sources of impactors onto the
Pluto-Charon system, to determine the main contributor and the whole
production of craters. Then, we will be able to contrast those studies
with observations, which will help us to understand the geological
processes and history of the surface of those worlds.