Question

Approximately how long does it take the sun to go through a full cycle of ʺbobbingʺ up and down in the

plane of the galaxy?

A) a few hundred years
B) a few million years
C) a few tens of millions of years
D) a few thousand years

Answer 1

The Sun takes about 225 million years to complete one orbit around the Milky Way's center, during which it 'bobs' up and down in the galaxy's plane. The correct time frame for this bobbing cycle is a few tens of millions of years.

Step-by-step explanation:

The question refers to the motion of the Sun through the Milky Way galaxy. The Sun, like other stars, orbits the center of the galaxy and has a motion that takes it above and below the plane of the galaxy. This oscillation or 'bobbing' is part of a larger cycle known as the galactic year.

Approximately, it takes the Sun about 225 million years to complete one orbit around the center of the Milky Way. Since this orbit is not perfectly circular, the Sun moves up and down relative to the galaxy's plane throughout this period. This movement above and below the plane of the galaxy takes millions of years, rather than hundreds or thousands. Therefore, the answer to the student's question is C) a few tens of millions of years.