A telescope would not be a telescope without instruments: these have the job of recording all the information collected by the telescope so that it can be studied and analysed later.
GRANTECAN issued a Request For Proposals (RFP) for the GTC’s two first-generation instruments in 1998. Six proposals for scientific instruments, all of which met the required specifications, were submitted in response to the RFP by groups of astronomers from various national and international centres and institutions. The science instruments would have to be developed for installation at the GTC in 2003. The proposals were evaluated by experts from Spain and abroad and, in March 1999, the teams working on them presented their designs to the astronomy community.
With this process completed, the GTC Science Advisory Committee named the three instruments it felt were best suited to go on to the final round in the selection process for the two Day One instruments.
The GTC will also have focusing instruments designed to harness its full potential. There will be four first-generation instruments, which are already in development:
ELMER, which will obtain conventional images; OSIRIS, a low-resolution spectrograph and imaging system; CanariCam, a thermal infrared (the longer wavelengths in the infrared spectrum) camera and spectrograph; as second-generation instruments, EMIR, a wide-field multi-object infrared spectrograph, and FRIDA, an Infrared Camera with Integral Field Unit that will work with light corrected by the GTC's Adaptive Optics System.