# ASTR BC 1753x Lecture Notes - Lecture 7: Semi-Major And Semi-Minor Axes, Orbital Period, Roygbiv

## Document Summary

No, it depends on your mass (the acceleration is the same) The gravitational force would be a factor of 4 smaller than now. The force of gravity from the sun is stronger. If gravity is stronger, velocity must also be higher. Kinetic motion forward balanced by gravitational pull inward. Kepler"s simple equation, p^2 = a^3 i valid only for objects orbiting the sun (p in years and a in. Newton derived a more general version using his law of gravity. Where m1 and m2 are the masses of any 2 objects. A = semi-major axis (in m or km) Can get the semi-major axis (distance from star estimate) from period of planet and mass of star. 4 in kay (gravity) and ch. 5 in kay (light) Different wavelengths of light = the electromagnetic spectrum. Type of light described by wavelength or the frequency (f x lambda = c) In the visible our eyes recognize f (or lambda) as color.