Our "hometown" is a vast, flat, disk-shaped collection of gas, dust, and stars called ___

How far is it across the Milky Way Galaxy?

How many stars are in the Milky Way Galaxy?

Where are we, Earthlings, located in the Milky Way Galaxy?

How many major spiral arms are in the Milky Way Galaxy?

The elongated, roughly cylindrical bar at the center of our galaxy is composed mostly of ___

The ancient Greeks called the glowing pathway of stars in the sky "galaxius", which means ___

Which astronomer discovered that the glowing cloudy Milky Way was actually made up of stars?

Early maps of the galaxy, which placed the Sun near the center, didn't account for ___

What "spherical balls of stars" helped determine that the Sun wasn't at the center of the galaxy?

From inside the Milky Way we see it as a broad line in the sky with a central bulge in the direction of ___

Interstellar dust restricts our view, so the structure of the Milky Way was determined by measuring ___

The spiral arms of our galaxy can best be thought of as ___

How long does our Sun take to orbit the galaxy?

Collisions of nebula in the spiral arms form massive, luminous, hot stars that make the arms appear ___

Our Sun is located just outside one of the smaller arms called ___

How long is the cylindrical bar of red stars at the center of our galaxy?

What object sits at the very center of our galaxy?

The black hole at the center of our galaxy has a mass of ___

The vast spherical cloud of old stars surrounding the Milky Way is called ___