that orbit them, but also the direct imaging of larger planets and possibly even the characterisation of their atmospheres. The telescope will attempt to image Earthlike exoplanets, which may be possible. Furthermore, the ELT's suite of instruments will allow astronomers to probe the earliest stages of the formation of planetary systems and to detect water and organic molecules in protoplanetary discs around stars in the making. Thus, the ELT will answer fundamental questions regarding planet formation and evolution. By probing the most distant objects the ELT will provide clues to understanding the formation of the first objects that formed: primordial stars, primordial galaxies and black holes and their relationships. Studies of extreme objects like black holes will benefit from the power of the ELT to gain more insight into time-dependent phenomena linked with the various processes at play around compact objects. The ELT is designed to make detailed studies of the first galaxies. Observations of these early galaxies with the ELT will give clues that will help understand how these objects form and evolve. In addition, the ELT will be a unique tool for making an inventory of the changing content of the various elements in the Universe with time, and to understand star formation history in galaxies. One of the goals of the ELT is the possibility of making a direct measurement of the acceleration of the Universe's expansion. Such a measurement would have a major impact on our understanding of the Universe. The ELT will also search for possible variations in the fundamental physical constants with time. An unambiguous detection of such variations would have far-reaching consequences for our comprehension of the general laws of physics. Instrumentation The telescope will have several science instruments and will be able to switch from one instrument to another within minutes. The telescope and dome will also be able to change positions on the sky and start a new observation in a very short time. Four of its instruments, the first generation, will be available at or shortly after first light, while two others will begin operations at a later stage. Throughout its operation other instruments can be installed to make new use of its high resolution. The first generation includes four instruments: MICADO, HARMONI and METIS, along with the adaptive optics system MAORY. HARMONI: The High Angular Resolution Monolithic Optical and Near-infrared Integral field spectrograph (HARMONI) will function as the telescope's