Julio Camargo

TL;DR: In this paper, the differences between positions as determined by optical (direct imaging) and very long baseline interferometry (VLBI) techniques of extragalactic sources listed in the second realization of the International Celestial Reference Frame (ICRF2) were investigated.

TL;DR: In this article, the authors observed a stellar occultation by the Galilean moon Europa (J2) and proposed a campaign for observing stellar occultations for all Galilean moons, where the authors measured the light flux of the occulted star and object to determine the time when the flux dropped with respect to one or more reference stars, and the time that it rose again for each observational station.

TL;DR: In this article, the authors used the Platform for Reduction of Astronomical Images Automatically (PRAIA) to perform a digital coronography to minimize the influence of the scattered light of Uranus on the astrometric measurements and to determine accurate positions of the main satellites.

TL;DR: In this paper, the authors investigated the link between the International Celestial Reference Frame (ICRF) and its optical Hipparcos-based representation on the northern hemisphere using the 0.6m Zeiss telescope at Belogradchik Observatory, Bulgaria.

TL;DR: In this article, the authors presented the TRAPPIST-South project at the La Silla Paranal Observatory in Spain with the support of the European Research Council under the European Community's H2020 (2014-2020/ERC grant agreement No. 669416 >LUCKY STAR>).