Bibcode
Moreno, Fernando; Licandro, Javier; Cabrera-Lavers, Antonio; Morate, David; Guirado, Daniel
Bibliographical reference
Monthly Notices of the Royal Astronomical Society
Advertised on:
9
2021
Citations
10
Refereed citations
9
Description
We report on the characterization of the dust activity and dynamical evolution of two faint active asteroids, P/2019 A4, and P/2021 A5, observed with the 10.4 m GTC using both imaging and spectroscopy. Asteroid P/2019 A4 activity is found to be linked to an impulsive event occurring some ±10 d around perihelion, probably due to a collision or a rotational disruption. Its orbit is stable over 100 Myr time-scales. Dust tail models reveal a short-term burst producing (2.0 ± 0.7) × 106 kg of dust for maximum particle radius rmax = 1 cm. The spectrum of P/2019 A4 is featureless, and slightly redder than the Sun. P/2021 A5 was active ~50 d after perihelion, lasting ~5 to ~60 d, and ejecting (8 ± 2) × 106 kg of dust for rmax = 1 cm. The orbital simulations show that a few percent of dynamical clones of P/2021 A5 are unstable on 20-50 Myr time-scales. Thus, P/2021 A5 might be an implanted object from the JFC region or beyond. These facts point to water-ice sublimation as the activation mechanism. This object also displays a featureless spectrum, but slightly bluer than the Sun. Nuclei sizes are estimated in the few hundred meters range for both asteroids. Particle ejection speeds (≍0.2 m s-1) are consistent with escape speeds from those small-sized objects.
Related projects
![Image of active asteroid P/2013 R3 (CATALINA-PANSTARRS) obtained with the 10.4m GTC telescope (La Palma, Spain). The nucleus of the object is splitted in at least four fragments (bright nucleus and fragments labeled A, B, and C) that remained active after the cometary-like spitting event Project Image](/sites/default/files/styles/crop_square_2_2_to_320px/public/images/project/Imagen%20Julia.jpg?h=a20dd341&itok=Mh16lYlm)
Minor Bodies of the Solar System
This project studies the physical and compositional properties of the so-called minor bodies of the Solar System, that includes asteroids, icy objects, and comets. Of special interest are the trans-neptunian objects (TNOs), including those considered the most distant objects detected so far (Extreme-TNOs or ETNOs); the comets and the comet-asteroid
Julia de
León Cruz