Front

What is an astronomical unit?

Back

The average distance between the Earth and the Sun.

Front

How does the mass of a star compare to that of a planet and a galaxy?

Back

A star has more mass than a planet and less mass than a galaxy.

Front

What color shift indicates a star is moving away from the solar system?

Back

Red shift.

Front

What type of galaxy is characterized by a smooth, featureless shape?

Back

Elliptical galaxy.

Front

Which galaxy is known as our home galaxy?

Back

Milky Way.

Front

What is the definition of a galaxy?

Back

A massive system of stars, stellar remnants, interstellar gas, dust, and dark matter bound together by gravity.

Front

What is the difference between a star and a planet?

Back

A star generates its own light through nuclear fusion, while a planet does not.

Front

What is a nebula?

Back

A giant cloud of dust and gas in space, often the birthplace of stars.

Front

What is the significance of the red shift in astronomy?

Back

It indicates that an object is moving away from the observer, suggesting the expansion of the universe.

Front

What are the three main types of galaxies?

Back

Spiral, elliptical, and irregular.