Answer:
60.85° counterclockwise
Explanation:
Data provided in the question:
a₁ = 1.0 AU
a₂ = 0.7 AU
Now,
The phase angle ( α ) is calculated using the formula
α = [tex]\pi\times(1-\frac{1}{2\sqrt{2}}\sqrt{(\frac{a_1}{a_2}+1)^3}\ )[/tex]
on substituting the respective values, we get
α = [tex]\pi\times(1-\frac{1}{2\sqrt{2}}\sqrt{(\frac{1.0}{0.7}+1)^3}\ )[/tex]
or
α = -1.062 radians
Here, the negative sign depicts the counterclockwise direction
Now,
1 radian = [tex]\frac{\textup{180}}{\pi}[/tex] degrees
therefore,
-1.062 radians = -1.062 × [tex]\frac{\textup{180}}{\pi}[/tex] degrees
or
-1.062 radians = -60.85°
Hence,
The planetary phase angle between them is 60.85° counterclockwise
