Spectroscopy and Extrasolar Planet Detection

The video provides an overview of the Doppler effect, explaining how it affects sound and light waves. It discusses the concepts of red and blue shifts, and how these shifts can be used to measure the motion of stars and detect exoplanets. The video also covers the application of the Doppler effect in understanding star rotation and binary star systems, as well as the proper motion of stars. Through examples and mathematical relationships, the video illustrates how astronomers use these principles to gather information about celestial bodies.

What happens to the frequency of sound waves as a source moves towards an observer?

• The frequency increases.

• The frequency remains constant.

• The frequency becomes zero.

• The frequency decreases.

In the context of light waves, what does a redshift indicate?

• The light source is moving away from the observer.

• The light source is stationary.

• The light source is changing color.

• The light source is moving towards the observer.

How is the Doppler Effect used to measure the velocity of stars?

• By calculating the star's brightness.

• By measuring the shift in the star's spectrum.

• By timing the star's rotation.

• By observing the color change of the star.

What is the significance of the width of spectral lines in understanding a star's rotation?

• It reveals the star's rotational speed.

• It shows the star's age.

• It indicates the star's temperature.

• It measures the star's distance from Earth.

What is the proper motion of a star?

• The star's rotational motion.

• The star's change in brightness.

• The star's motion across the sky.

• The star's motion towards or away from Earth.

How can the Doppler Effect help in detecting binary star systems?

• By observing the color of the stars.

• By measuring the distance between the stars.

• By detecting the red and blue shifts in their spectra.

• By calculating the stars' temperatures.

Why is it difficult to directly observe extrasolar planets?

• They are too small.

• They move too quickly.

• They are too far away.

• The parent star's brightness overwhelms them.

What kind of graph is used to fit the data when detecting extrasolar planets?

• Linear graph

• Bar graph

• Sinusoidal graph

• Exponential graph

What does a sinusoidal graph indicate in the context of extrasolar planet detection?

• The planet's temperature

• The planet's orbit period

• The planet's size

• The planet's distance from its star

What effect does a planet have on its parent star that helps in its detection?

• It alters the star's temperature.

• It causes the star to wobble.

• It changes the star's color.

• It increases the star's brightness.