papers

Publications (9)

astro-ph.EP2016

Nonconservative extension of Keplerian integrals and a new class of integrable system

Javier Roa

The invariance of the Lagrangian under time translations and rotations in Kepler's problem yields the conservation laws related to the energy and angular momentum. Noether's theore…

astro-ph.EP2021

A novel approach to asteroid impact monitoring and hazard assessment

Javier Roa, Davide Farnocchia, Steven R. Chesley

Orbit-determination programs find the orbit solution that best fits a set of observations by minimizing the RMS of the residuals of the fit. For near-Earth asteroids, the uncertain…

astro-ph.EP2018

Stability of exomoons around the Kepler transiting circumbinary planets

Adrian S. Hamers, Maxwell X. Cai, Javier Roa +1

The Kepler mission has detected a number of transiting circumbinary planets (CBPs). Although currently not detected, exomoons could be orbiting some of these CBPs, and they might b…

astro-ph.GA2014

Optical imaging for the Spitzer Survey of Stellar Structure in Galaxies. Data release and notes on interacting galaxies

Johan H. Knapen, Santiago Erroz-Ferrer, Javier Roa +4

(Abridged) The Spitzer Survey for Stellar Structure in Galaxies (S4G) and its more recently approved extension will lead to a set of 3.6 and 4.5 micron images for 2829 galaxies, wh…

physics.class-ph2020

Uniform formulation for orbit computation: the intermediate elements

Giulio Baù, Javier Roa

We present a new method for computing orbits in the perturbed two-body problem: the position and velocity vectors of the propagated object in Cartesian coordinates are replaced by…

math-ph2016

Stability and chaos in Kustaanheimo-Stiefel space induced by the Hopf fibration

Javier Roa, Hodei Urrutxua, Jesús Peláez

The need for the extra dimension in Kustaanheimo-Stiefel (KS) regularization is explained by the topology of the Hopf fibration, which defines the geometry and structure of KS spac…