Astronomy Astronomy Galaxies and the Milky Way 1

Question 1

What type of galaxy is the Milky Way?

Accepted Answer

Barred spiral galaxy

Answer

The Milky Way is classified as a barred spiral galaxy, with a central bar-shaped structure from which spiral arms extend outward.

Question 2

What is the name of the supermassive black hole at the center of the Milky Way?

Accepted Answer

Sagittarius A*

Answer

Sagittarius A* (Sgr A*) is the supermassive black hole at the center of the Milky Way, with a mass of about 4 million solar masses.

Question 3

How long does it take the Sun to complete one orbit around the Milky Way's center?

Accepted Answer

About 225 million years

Answer

The Sun orbits the Milky Way center once every approximately 225-250 million years, a period sometimes called a 'cosmic year' or 'galactic year.'

Question 4

What are the two largest satellite galaxies of the Milky Way?

Accepted Answer

Large and Small Magellanic Clouds

Answer

The Large and Small Magellanic Clouds are the two largest satellite galaxies of the Milky Way, visible to the naked eye from the Southern Hemisphere.

Question 5

What is the Andromeda Galaxy's designation in the Messier catalog?

Accepted Answer

M31

Answer

The Andromeda Galaxy is cataloged as M31 in Charles Messier's catalog and is the nearest large spiral galaxy to the Milky Way.

Astronomy Practice Test