Why do astronomers need large telescopes?
		• Large telescopes can collect more light – Can detect fainter objects – Have more light for specialized analysis. • Large telescopes can form more detailed images – Waves spread out as they go through an opening. • The larger the opening, the less they spreads out. • The longer the wavelength the more they spread out • Angle of spread   /D  where D is Diameter of telescope • Radio telescopes have to be much bigger than visible ones