Side by side with the biggest

With a primary mirror of 60cm in diameter, the TRAPPIST telescope promises to be more than effective for the missions which it will be asked to preform. It has been installed in a dome which belonged to the University of Geneva, at the ESO Silla site in Chile, with the aid of Virginie Chantry, a ULg postdoctoral student who is there at the site. TRAPPIST has the singular advantage of being robotised and can thus be entirely operated from Liège, at a distance of some 12,000 kilometres. ‘It even has its own weather station, which will allow it to automatically reshut its dome if the weather worsens,’ specifies Pierre Magain, a professor and administrative manager of the TRAPPIST project. ‘As for the information produced, it will be gathered by a double filtered runner wheel, one for the exoplanets, the other for the comets. It is enough to choose the filter beforehand depending on what will be observed.,’ A CCD camera will record the images captured. A pre-processing of the data will take place on site, before the main results are sent to Liège for the final analysis.

Of course it will not have the same missions as the international telescopes, such as the VLT, whose mirror has a diameter of over 8 metres. ‘But the VLT is really there to observe heavenly bodies at gigantic distances,’ continues Emmanuël Jehin. ‘In the present case it is more useful for us to have our own telescope; we will be able to use it for as long as we wish, which is very important in terms of carrying out our projects successfully, as they require long periods of observation.’

‘For this type of research,’ adds Pierre Magain, ‘it is important to have available a telescope which is ours to use exclusively. For example, for the comets, certain of them are known but a lot arrive without a warning cry. And there we have to be capable of observing them at the opportune moment. As for the exoplanets, we have to be able to observe them at the precise moment they are in transit, when they pass in front of their star. Such transits last several hours, even a whole night.’ A magnificent and more than useful investment in this millennial quest for other life forms, made possible by financial support from the FNRS and the Geneva observatory. The Liège team will moreover work in complete collaboration with the Swiss team, led by Didier Queloz.