Ask a high school physics question! Questions about conservation of angular momentum! seeking process

There is not enough information in this question. The solution of tzredhat on the first floor is only valid when the distances mentioned in the question are perihelion and aphelion respectively. The real speed needs to be solved by energy conservation. The momentum and gravitational potential at 9.3X10^10 meters are the same as those at 4.1X10^12 meters.

If this is not a competition question, you can use the "inappropriate" conservation of angular momentum to do it. Of course, the expression in the question is obviously incorrect (does anyone in their right mind use such a funny expression as "a Halley's Comet"? ? Black humor like "a mother of the question maker").

If you need specific steps for a competition question, please contact me.