Formation of the Milky Way

The Milky Way galaxy most likely formed

• from collisions of larger galaxies.

• from the big bang itself.

• from collisions of smaller irregular galaxies.

• from collisions of spiral galaxies.

Evidence for the Milky Way forming from collisions of smaller galaxies include

• chaotic orbits of spiral arm stars.

• chaotic orbits of the Sun and other disk stars.

• chaotic orbits of halo stars.

• variable stars in globular clusters.

Other evidence for Milky Way formation includes

• orderly movement of disk stars.

• only new star formation in the disk.

• new star formation in the halo regions.

• new stars in the halo region.

Tags

NGSS.MS-ESS1-2

How do the vast majority of stars orbit in the Milky Way?

• in chaotic or random orbits

• in orbits that are retrograde

• in fixed or unchanging orbits

• in mostly one direction around the central bulge

Tags

NGSS.MS-ESS1-2

How can astronomers "see" past the vast, light-obstructing dust clouds of the Milky Way?

• By using the Hubble Space Telescope (HST).

• By using visible light telescopes on the ground.

• They make educated guesses.

• By using ground-based radio telescopes.

Tags

NGSS.HS-PS4-3

What did astronomers discover about the structure of the Milky Way using radio studies?

• it has many massive black holes

• it has billions of stars

• it has no real structure (irregular)

• it has at least 5 major spiral arms

Our Sun (and solar system) lies in the _____ arm of the Milky way.

• Perseus

• Norma

• Sagittarius

• Orion

Tags

NGSS.MS-ESS1-2

What are "spiral density waves?"

• waves that form from star explosions

• waves that become compressed triggering star formation

• waves of gas & dust

• an area in or near the arms in which stars move in & out

Kepler's third law of planetary motion uses a planet's orbital speed and distance to

• predict planetary composition.

• find the mass of a black hole.

• find the mass of that planet.

• discover new solar systems

Tags

NGSS.MS-ESS1-2

Kepler's third law can be slightly modified to apply to

• the mass of stars orbiting in a galaxy.

• the total mass of planets in a galaxy.

• the mass of a black hole.

• the chaotic orbit of halo stars.

Tags

NGSS.HS-ESS1-4