Exoplanet Test

The existence of exoplanets are typically known though ....

• Theoretical justification

• direct imaging

• effects on the star that the planet orbits

• nothing - they don't exist

An astronomer is taking spectra of a star which has a large planet. She makes measurements of the wavelength of the Balmer Alpha line (656.3 nm in laboratory observation) and observes it at 656.5 nm. What can be said about the star at this moment?

• The star has a positive radial velocity and is moving away from Earth

• The star has a negative radial velocity and is moving away from Earth

• The star has a positive radial velocity and is moving towards Earth

• The star has a positive radial velocity and is moving towards Earth

In looking at a radial velocity curve, if you notice that one star has a higher amplitude than another star of equal mass, what can you assume about the orbiting planet?

• The star with the larger amplitude would have a planet of higher mass

• The star with the larger amplitude would have a planet of lower mass

• The star with the larger amplitude would have a planet that has a larger semi major axis

• The star with the larger amplitude would have a planet that has an eccentricity close to 0

Exoplanets discovered using the radial velocity technique are most likely to be described as....

• Far from the star and low mass

• close to the star and low mass

• close to the star and high mass

• Far from the star and high mass

Which planet in our solar system would have the greatest impact on our Sun's radial velocity curve and/or transit depth?

• Neptune

• Saturn

• Jupiter

• Earth

• Mars

The Kepler Space Telescope is searching for extrasolar planets by the transit method. It is necessary for Kepler to photometrically monitor a large number of stars because....

• A. Only a small percentage of system are likely to have planets

• B. Only a small percentage of systems have the correct geometry for transit to be observed

• C. Planets will only be transiting the star for a small percentage of time

• A & B

• B & C

What is the major shortcoming of using the radial velocity technique for detecting exoplanets?

• The orbital period can take too long

• The technique is unable to detect earth sized planets

• The method can only detect planets within 100 light years

• The technique only works on high luminosity stars.

What property of a planet would change the symmetry of a radial velocity wave?

• Mass

• Distance (semi-major axis)

• Eccentricity

• Period

What happens to the radial velocity curve if you increase the semi major axis?

• The system period increases

• The system period decreases

• The system period stays the same

• The radial velocity curve increases

If the mass of a star decreases (and the planet's mass stays the same), then the amplitude of the radial velocity curve will__________.

• Disappear

• Increase

• Decrease

• Stay the same