SUS1501 ASSIGNMENTS 2-8 2026 FULL
PRACTICE AND SOLUTIONS GUIDE
◉ Select the reasons it is easier to take a picture of a young
exoplanet using infrared wavelengths than visible light Answer:
Forming exoplanets are hot and generate their own light
Stars are dimmer in infrared than visible wavelengths
◉ We have detected many exoplanets, but we do not have many
images of these planets. What is most prevalent reason why not?
Answer: The exoplanets are much dimmer than the stars. This
makes them difficult to see
◉ The image shows the result of what method of exoplanet
detection? Answer: Radial velocity
◉ How do we use the radial velocity method to find exoplanets?
Answer: We measure changes in the wavelength of the star's light
resulting from its wobble in response to the orbiting planet
◉ A planet that orbits a star other than the Sun is called an ____
Answer: exoplanet
,◉ Identify the true statements with regard to the direct imaging of
exoplanets. (Select all that apply.) Answer: The exoplanet is young.
The exoplanet is a gas giant.
The exoplanet is far from the star.
Use an infrared telescope and camera.
◉ Match the exoplanet feature with how it affects our ability to
detect the planet. Answer: Massive ---- Makes Doppler shifts in the
star's spectrum bigger
Far from the parent star ---- Takes more time to detect motion and
find the period
Orbital plane is face-on (perpendicular to the line of sight) ----
Minimizes the Doppler effect and eliminates any chance of transits
Large radius ---- Increases the probability and effect of transits
◉ Match the exoplanet detection method to the description Answer:
Radial Velocity ---- We measure changes in the wavelength of the
star's light due to its velocity in response to the planet.
Transit ---- We measure a decrease in the brightness of a star's light
when a planet passes in front of the star
, Direct imaging ---- We take infrared images of a star and carefully
subtract as much of the light of the star as possible to reveal any
nearby glowing planets.
Gravitational lensing ---- As a planet and star pass in front of a
background star, we measure the increase in brightness of the
background star.
◉ Rank the exoplanets from the easiest (top) to the hardest
(bottom) to detect using the Doppler method Answer: A massive
Jovian planet close to its star with its orbit edgewise to Earth
A dense super-earth close to its star with its orbit edgewise to Earth
A massive Jovian planet moderately far from the star and in an orbit
at 45 degrees to the direction of Earth
An earth-mass planet in an orbit perpendicular to the direction of
the Earth
◉ Select the quantity that is reliably and unambiguously found when
using the radial velocity method to discover exoplanets Answer: The
orbital period of the planet
PRACTICE AND SOLUTIONS GUIDE
◉ Select the reasons it is easier to take a picture of a young
exoplanet using infrared wavelengths than visible light Answer:
Forming exoplanets are hot and generate their own light
Stars are dimmer in infrared than visible wavelengths
◉ We have detected many exoplanets, but we do not have many
images of these planets. What is most prevalent reason why not?
Answer: The exoplanets are much dimmer than the stars. This
makes them difficult to see
◉ The image shows the result of what method of exoplanet
detection? Answer: Radial velocity
◉ How do we use the radial velocity method to find exoplanets?
Answer: We measure changes in the wavelength of the star's light
resulting from its wobble in response to the orbiting planet
◉ A planet that orbits a star other than the Sun is called an ____
Answer: exoplanet
,◉ Identify the true statements with regard to the direct imaging of
exoplanets. (Select all that apply.) Answer: The exoplanet is young.
The exoplanet is a gas giant.
The exoplanet is far from the star.
Use an infrared telescope and camera.
◉ Match the exoplanet feature with how it affects our ability to
detect the planet. Answer: Massive ---- Makes Doppler shifts in the
star's spectrum bigger
Far from the parent star ---- Takes more time to detect motion and
find the period
Orbital plane is face-on (perpendicular to the line of sight) ----
Minimizes the Doppler effect and eliminates any chance of transits
Large radius ---- Increases the probability and effect of transits
◉ Match the exoplanet detection method to the description Answer:
Radial Velocity ---- We measure changes in the wavelength of the
star's light due to its velocity in response to the planet.
Transit ---- We measure a decrease in the brightness of a star's light
when a planet passes in front of the star
, Direct imaging ---- We take infrared images of a star and carefully
subtract as much of the light of the star as possible to reveal any
nearby glowing planets.
Gravitational lensing ---- As a planet and star pass in front of a
background star, we measure the increase in brightness of the
background star.
◉ Rank the exoplanets from the easiest (top) to the hardest
(bottom) to detect using the Doppler method Answer: A massive
Jovian planet close to its star with its orbit edgewise to Earth
A dense super-earth close to its star with its orbit edgewise to Earth
A massive Jovian planet moderately far from the star and in an orbit
at 45 degrees to the direction of Earth
An earth-mass planet in an orbit perpendicular to the direction of
the Earth
◉ Select the quantity that is reliably and unambiguously found when
using the radial velocity method to discover exoplanets Answer: The
orbital period of the planet
