NATS 1745 Lecture 12: Lesson 12

• School: York University
• Department: Natural Science
• Course: NATS 1745
• Professor: Robin Metcalfe

Document Summary

Advantages of radio waves: can be detected on earth both night and day (not overwhelmed by sunlight) as well as through clouds. Radio waves are the longest waves and can actually be detected from space easier than visible light waves as long as you have the right instrumentation. Sun produces very little radio waves: easily detected with ground-level telescopes (they completely pe(cid:374)et(cid:396)ate ea(cid:396)th"s atmosphere). The higher the telescope, the thinner the atmosphere, and therefore the more light reaching the atmosphere. A radio dish can be placed anywhere in the world: reflect off most metallic surfaces, no absorbed by interstellar dust, strongly emitted by distant (young) galaxies, allowing us to observe galaxies as they appeared in the distant past. Distant galaxies produce more radio emission than they do visible light that why radio dishes are used to probe the most distant regions of space. Radio emission from our galaxy: (cid:1005)9(cid:1007)(cid:1005): ja(cid:374)sk(cid:455) (cid:894)(cid:862)fathe(cid:396) of (cid:396)adio ast(cid:396)o(cid:374)o(cid:373)(cid:455)(cid:863)(cid:895) dete(cid:272)ted (cid:396)adio e(cid:373)issio(cid:374) f(cid:396)o(cid:373) ou(cid:396) gala(cid:454)(cid:455).