# Consider a spacecraft in an elliptical orbit around the Sun with a semi-major axis of 0.5AU and an orbital eccentricity of 0. Describe what will…

- Consider a spacecraft in an elliptical orbit around the Sun with a semi-major axis of 0.5AU and an orbital eccentricity of 0.5.

- Describe what will happen to the spacecraft. Be as quantitative as possible. (Neglect the effect of the solar wind, and Poynting-Robertson effect and consider only the effects from radiation pressure and gravity from the Sun).
- What is the area of the solar sail that is required so that the forces associated with radiation pressure and gravity exactly cancel? You may assume the sail itself has negligible mass. Assume the mass of the spacecraft is 5000 kg, and the radiation pressure coefficient, Q=2.
- Suppose that its new orbit takes it directly by Pluto. How long will it take the spacecraft to reach Pluto? (Assume Pluto is at a distance of 40AU from the Sun).