Galactic Interactions and Properties

The video discusses the motion of the Andromeda galaxy towards the Milky Way and explains how to calculate the Doppler shift for a star within Andromeda. It covers the concept of blue shift, estimating the time until the galaxies collide, and concludes with a discussion on galaxy collisions and further reading suggestions.

What is the primary focus of the video regarding the Andromeda and Milky Way galaxies?

• The distance between the two galaxies

• The motion of the Andromeda galaxy towards the Milky Way

• The age of the Milky Way galaxy

• The size of the Andromeda galaxy

What is the speed of approach between the Andromeda and Milky Way galaxies?

• 1.1 x 10^6 meters per second

• 5.0 x 10^6 meters per second

• 3.0 x 10^8 meters per second

• 2.5 x 10^6 meters per second

What is the calculated Doppler shift (Delta Lambda) for the hydrogen alpha line?

• 4.8 nanometers

• 3.6 nanometers

• 2.4 nanometers

• 1.2 nanometers

What does a blue shift indicate about the wavelength of light?

• The wavelength remains the same

• The wavelength is longer

• The wavelength is shorter

• The wavelength is irrelevant

What is the significance of the hydrogen alpha line in this context?

• It measures the distance to the galaxy

• It indicates the size of the galaxy

• It is used to measure the Doppler shift

• It shows the age of the star

How many years are estimated for the collision of the Andromeda and Milky Way galaxies assuming constant speed?

• 500 million years

• 2 billion years

• 1 billion years

• 680 million years

Why is the formula 'distance equals rate times time' not entirely accurate for calculating the collision time?

• Because the distance is too large

• Because the speed is not constant due to gravitational attraction

• Because the time is measured in light-years

• Because the galaxies are not moving

What is the conversion factor for one light year into meters?

• 3.15 x 10^7 meters

• 6.0 x 10^12 meters

• 9.46 x 10^15 meters

• 1.5 x 10^8 meters

What is the primary reason star collisions are rare during galaxy interactions?

• Stars are not affected by gravity

• Stars move too fast

• Stars are too small compared to galaxies

• Stars are too far apart

What is the expected outcome when galaxies collide?

• Galaxies will merge instantly

• Gas and dust will interact due to gravity

• Galaxies will pass through each other without interaction

• Stars will frequently collide