Phobos, the inner satellite of Mars, has a diameter of about 28 km and circles about 6000 km above the Martian surface. Approximately what is the angular diameter of Phobos when viewed from Mars (in degrees)?
A)1/100
B)1/4
C)1
D)5 1/2

Question

Quizplus · Accepted Answer

The angular diameter can be calculated using the formula:

angular diameter = (diameter of object / distance from observer) x (180 / π)

Substituting the values, we get:

angular diameter = (28 km / 6000 km) x (180 / π) = 0.24 degrees

Since the value is closest to 1/4, the answer is B) 1/4.

Phobos, the Inner Satellite of Mars, Has a Diameter of About