The short answer is – their size increases. However, you have to be careful, how is it done. In years 60. In the 1980s, the Soviet Union tried to prove its superiority over the West, building a powerful telescope on Mount Pastukhov in the Caucasus. Its mirror was in diameter 6 meters – almost a meter more than the famous telescope on Mount Palomar in California – and it weighed 42 tony. Unfortunately, the project turned out to be a disaster: the mirror was so big, days passed, before a thermal equilibrium was established between him, and the surroundings, and the deformation and vibration occurred almost continuously. So this telescope never really worked like that. Since then, the largest telescopes use a very thin mirror consisting of numerous segments, whose layout is controlled by the computer – Keck's twin telescopes atop Mauna Kea in Hawaii have 10-meter mirrors, each composed of 36 hexagonal mirrors in diameter 1.8 metra. From the end of the years 80. In the 1980s, astronomers began to experiment with new technologies, which made telescopes even more powerful. One of the methods, called interferometry, it consists in using two or more mirrors positioned at a great distance from each other and combining the images obtained in them into one whole using a computer.
It is planned to engage the twin giants of Keck in this way – would have arisen then “virtual” telescope: with a mirror diameter 85 meters, and after attaching smaller telescopes – even a hundred. This would allow astronomers to see details of space objects with dimensions 0.005 seconds of arc – this is equivalent to reading the newspaper from a distance 30 Kilometers.
However, this is just the beginning: even more wonderful results will be obtained if the interference telescopes are launched into space. Currently, the largest telescope in the near-Earth space is 2.5 meter Hubble Space Telescope – he weighs 11 ton, that is, the maximum, how much can be carried into orbit with the space shuttle. Folding cosmic interferometers will be much easier to place in near-earth space.
In year 2005 space is to be found “Space Interferometry Mission” (SIM), whose images will be four times sharper than those from the Hubble telescope, while the weight is five times less. “Terrestrial Planet Finder” (TPF), which launch is planned for 2011 year, will upload images 40 times sharper than Hubble. Finally, Planet Finder Device will be a group of TPF class interferometers, each of which is to consist of four 8 meter telescopes. Their combined power will make it possible to spot planets orbiting distant stars.
