Astronomy 1021 Lecture Notes - Lecture 3: Observable Universe

• School: Western University
• Department: Astronomy
• Course: Astronomy 1021
• Professor: Robert Cockcroft

Document Summary

Dwarf planets- eris, pluto, haumea, makemake, ceres: there is a limit to the size of stars, when the star loses the balance of power the star implodes. Earth facts: the earth is 3. 85 x 105 km away from moon, and 1. 5 x 108 km from sun, people think it is much closer, the earth is significantly larger. Planets order from closest to the sun first: mercury, venus, earth & moon, mars, jupitar, saturn, uranus (19 au, neptune, pluto. Speed of light: c = 3 x 108 m/s, 7. 5 times around the earth in one second, fastest speed anything in the universe can go. Light-year: a light year is a distance, it is the distance that a light can travel in 1 year, distance = speed x time. Light year = 3 x 108 m/s x 1 year. = 3 x 108 m/s x 3. 15 x 107 s.