The Zadko Telescope: Exploring the transient Universe

International audienceThe Zadko telescope is a 1 m f/4 Cassegrain telescope, situated in the state of Western Australia about 80-km north of Perth. The facility plays a niche role in Australian astronomy, as it is the only meter class facility in Australia dedicated to automated follow-up imaging of alerts or triggers received from different external instruments/detectors spanning the entire electromagnetic spectrum. Furthermore, the location of the facility at a longitude not covered by other meter class facilities provides an important resource for time critical projects. This paper reviews the status of the Zadko facility and science projects since it began robotic operations in March 2010. We report on major upgrades to the infrastructure and equipment (2012–2014) that has resulted in significantly improved robotic operations. Second, we review the core science projects, which include automated rapid follow-up of gamma ray burst (GRB) optical afterglows, imaging of neutrino counterpart candidates from the ANTARES neutrino observatory, photometry of rare (Barbarian) asteroids, supernovae searches in nearby galaxies. Finally, we discuss participation in newly commencing international projects, including the optical follow-up of gravitational wave (GW) candidates from the United States and European GW observatory network and present first tests for very low latency follow-up of fast radio bursts. In the context of these projects, we outline plans for a future upgrade that will optimise the facility for alert triggered imaging from the radio, optical, high-energy, neutrino, and GW bands

TAROT: a network for space surveillance and tracking operations

International audienceTAROT: a network for space surveillance and tracking operations The TAROT (Télescope à Action Rapide pour les Objets Transitoires – Rapid Action Telescope for Transient Objects) network of telescopes consists of two 25cm aperture telescopes located at the Calern Observatory (TCA, OCA, France), the La Silla Observatory (TCH, ESO, Chile), and a 18cm telescope at Les Makes Observatory, (TRE, France). In addition we use the Zadko 1m telescope at the Gingin Observatory (ZDK, UWA, Australia). A central service in France, called CADOR (Centre d’Analyse des Données des Observatoires Robotiques, Centre for the Data Analysis of Robotic Observatories), acts as an interface for users, runs the scheduling system over the network, archive the data and run the core database. Since 1999 we perform observations of Resident Space Objects (RSO). Over the time we have implemented the observation of RSOs, mostly debris, on the geostationary orbit, and of passing objects in eccentric orbits, such as the GTO, or MEO/HEO. A specific data reduction pipeline with new methods for the image analysis has been developed and implemented by the CNES space debris modelling and risk assessments office to extract, process Space observations and to catalogue RSOs. As an example, in 2015, TCA has performed over 17000 measurements over the GEO monthly (average). TRE has been adapted to the observation of RSOs in November 2016, and it has made for its first 12 nights over 11000 measurements. In 2016, preliminary results show that the availability of the telescopes (TCA and TCH) is on the order of 90%. The TAROT network was recently used to observe the Arianne V233 Galileo launch, allowing observing the separation of the four satellites from the upper stage of the launcher, acquiring rare images of the passivation phase. We are now implementing operational procedures to use the TAROT network for the support of the CAESAR collision assessment system of the CNES. In this paper we present here the TAROT network, the methods and strategies we have developed, as well as statistics of measurements, some specific examples, and the perspective of the network within the context of Space Surveillance and Tracking