ASTR 100 Chapter Notes - Chapter 5: Dim Stars, Magic In Harry Potter, Transparency And Translucency

• School: Ball State University
• Department: Astronomy
• Course: ASTR 100
• Professor: Ryan Bartholomew

Document Summary

Teles(cid:272)ope gathers (cid:373)u(cid:272)h (cid:373)ore light tha(cid:374) e(cid:374)ters (cid:455)our e(cid:455)e"s pupil, so (cid:373)a(cid:374)(cid:455) stars (cid:271)e(cid:272)o(cid:373)e visible. Can collect light for a long period of time: allows it to record far fainter signals, showing objects you cannot see with the naked eye. Larger = brighter image, which allows us to see dim stars: describe the size by the diameter of the lens or mirror, doubling a lens/mirror increases the lg area by four. Lens must be supported at its edges so as not to block light passing through it. Transparent materials bring light of different colors to a focus at slightly different distances from the lens. Must keep local radiation from entering the detectors: most infrared, ultraviolet, and x ray radiation cannot penetrate the. Must use a telescope in space, operated remotely from the ground. Or, more rarely, send an astronaut into space: observatories on the ground and in space. The largest telescopes are often national or international facilities.