Astronomy: Exploring Time and Space - Week 4

The Tools of Astronomy Telescopes Gallileoscope 1 inch diameter over 400 years ago, modern telescopes now have diameters of 8 or 10 meters. Telescopes can also be used in invisible light wavelengths, e.g. ultraviolet, infrared, radio. James Webb Space Telescope will bring space astronomy to the level of large ground telescopes, 6.5 meter mirror. Ground based telescopes cost about a billion dollars. Hubble Space Telescope cost about $6-8 billion.
Read more...