1. Imagine that you heard someone announce each of the following discoveries. Knowing what you know about the Solar System, say whether each one makes sense or does not make sense, and then briefly explain your reasoning.
a. A meteorite (remember what that means!) that, based on radiometric dating, has an age of 7.9 billion years.
2. Escape speed from Titan
In class we have talked about escape speeds a number of times, including when we talked about the loss of atmospheres. This is the speed that something will need to have in order to escape from the gravitational pull of a planet, moon, etc. It depends on the mass of the planet, moon, etc., and how far the object is from the center of the planet or moon when it starts. In this problem we will calculate escape speeds from the surface of Titan. You can calculate the escape speed from the surface of a planet or moon of mass M by the formula v = √ 2GMR where v is the escape speed from the surface and R is the radius of the object (planet, moon, star, etc.).
[NOTE: This formula can be derived by setting the gravitational potential energy (GM1M2/R) equal to the kinetic energy ((1/2)M2v2) and then rearranging to solve for v].
In this problem, I will give you very rough ratios to make the math a bit easier. The mass of Earth is 40 times larger than the mass of Titan, while the radius of Earth is 2.5 times larger than the radius of Titan.
(a) Calculate the ratio of the escape speed on Earth to the escape speed on Titan, vE/vT
(b) If the escape speed from the surface of Earth is 11 km/s, use your answer to part (a) to calculate the escape speed from the surface of Titan.