# But that's too fast!

A new planet has just entered the solar system with volume one-third and average density half that of the sun. If the distance between the planet and the sun is $$90 \text{ km}$$, then find the total time taken by the planet to revolve around the center of mass of the planet-sun system. Submit your answer in milliseconds.

Details and Assumptions:

• Take the value of $$G$$ (universal gravitational constant) as $$6.67 \times {10}^{-11}$$ SI units.
• Take the mass of the sun as $$2 \times {10}^{30}\text{ kg}$$.
• Neglect the gravitational forces acting on the planet-sun system due to the other planets in the solar system.
• Assume the planet to revolve in a circular path around the sun.

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