Astronomy 1021 Lecture 6: Astronomy - Chapter 6

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

Document Summary

Describe basic factors about the solar system: constituents and their orbits, mass, location in the milky way, how it is measured. Three techniques are used in studying the solar system: imaging, spectroscopy, timing. Transit of venus (passing across the sun) helped us give absolute differences. Today we use spacecraft data and radar systems. Telescopes can measure the angular diameter of planets, and with distance and angular size we can know the absolute size. Measure angular distances (separation between two objects as perceived by observer), orbits and periods. This information gives you planets mass, and with the mass and radius, we can calculate the average density. Hampered by location (earth or earth"s orbit) Cheaper, can be used long term and upgraded. Lots of new objects still to find. Can get closer to solar system objects (better spatial measurements) Take a long time to build, launch, travel time, very expensive.