<P> Unlike optical telescopes which possess simple aluminized parabolic surfaces ( mirrors ) , X-ray telescopes generally use a Wolter telescope consisting of nested cylindrical paraboloid and hyperboloid surfaces coated with iridium or gold . X-ray photons would be absorbed by normal mirror surfaces , so mirrors with a low grazing angle are necessary to reflect them . Chandra uses four pairs of nested mirrors , together with their support structure , called the High Resolution Mirror Assembly ( HRMA ) ; the mirror substrate is 2 cm - thick glass , with the reflecting surface a 33 nm iridium coating , and the diameters are 65 cm , 87 cm , 99 cm and 123 cm . The thick substrate and particularly careful polishing allowed a very precise optical surface , which is responsible for Chandra 's unmatched resolution : between 80 % and 95 % of the incoming X-ray energy is focused into a one - arcsecond circle . However , the thickness of the substrates limit the proportion of the aperture which is filled , leading to the low collecting area compared to XMM - Newton . </P>
<P> Unlike optical telescopes which possess simple aluminized parabolic surfaces ( mirrors ) , X-ray telescopes generally use a Wolter telescope consisting of nested cylindrical paraboloid and hyperboloid surfaces coated with iridium or gold . X-ray photons would be absorbed by normal mirror surfaces , so mirrors with a low grazing angle are necessary to reflect them . Chandra uses four pairs of nested mirrors , together with their support structure , called the High Resolution Mirror Assembly ( HRMA ) ; the mirror substrate is 2 cm - thick glass , with the reflecting surface a 33 nm iridium coating , and the diameters are 65 cm , 87 cm , 99 cm and 123 cm . The thick substrate and particularly careful polishing allowed a very precise optical surface , which is responsible for Chandra 's unmatched resolution : between 80 % and 95 % of the incoming X-ray energy is focused into a one - arcsecond circle . However , the thickness of the substrates limit the proportion of the aperture which is filled , leading to the low collecting area compared to XMM - Newton . </P>
what kind of telescope is the chandra observatory
what kind of telescope is the chandra observatory
X-ray telescopes
X-ray telescopes