Planets

Question 1

Kepler’s laws

Answer 1

• Planets orbit the sun in ellipses with the sun at one focus
• Planets sweep out equal areas in equal times
• Time period squared is proportional to the semi major axis cubed

Question 2

Stars in a binary system

Answer 2

Same time period

V1/V2=R1/R2=M2/M1

Question 3

Planet hunting techniques

Answer 3

Radial velocity - velocity of star

Transit method - dip in luminosity of star