What is the Moon's approximate diameter if it subtends about 30 arcminutes in the sky and is at about 400,000 km from Earth at the time of observation?
A) 350 km
B) 35,000 km
C) 3500 km
D) 60 km

Question

Quizplus · Accepted Answer

The Moon's angular diameter is about 0.5 degrees (30 arcminutes), and using the small angle formula, the diameter can be calculated as: Diameter = Distance * Angular Diameter (in radians). Converting 30 arcminutes to radians and using the distance of 400,000 km, the approximate diameter is 3,500 km.

What Is the Moon's Approximate Diameter If It Subtends About