Exploring the Universe: Galaxies and Their Mysteries

What term was used in the early 20th century to describe the mysterious 'faint fuzzies' in the sky?

• Nebulae

• Star clouds

• Galactic spirals

• Spiral clusters

Who argued that the Milky Way was the entirety of the universe in the 1920 debate?

• Heber Curtis

• Harlow Shapley

• Edwin Hubble

• Milton Humason

What discovery by Edwin Hubble was crucial in proving that the Milky Way is not the only galaxy?

• The existence of dark matter

• Cepheid variables in the Andromeda Nebula

• The rotation of the Milky Way

• The red shift of distant galaxies

Which type of galaxy is characterized by a flat rotating disk and spiral arms?

• Elliptical

• Irregular

• Spiral

• Peculiar

What is a key feature of elliptical galaxies?

• Spiral arms

• Young, blue stars

• Bar-shaped structures

• Lack of gas and dust

How do astronomers believe elliptical galaxies are formed?

• As remnants of the Big Bang

• Through the expansion of the universe

• By the merging of spiral galaxies

• From the collapse of a single massive star

What happens when two galaxies collide?

• They explode upon impact

• They pass through each other without any interaction

• They merge to form a new type of galaxy

• They bounce off each other

What evidence do we have of the Milky Way consuming smaller galaxies?

• Detection of dark matter

• The presence of black holes

• Streams of stars from dwarf galaxies

• Observation of galactic explosions

What are peculiar galaxies?

• Galaxies with extremely bright cores

• The smallest galaxies in the universe

• Galaxies with no definite shape

• Galaxies formed by the collision of two or more galaxies

Which of the following is a characteristic feature of irregular galaxies?

• They are the most common type of galaxy

• They have a chaotic shape with no clear structure

• They are typically very large

• They have a central bulge and spiral arms