1. What does the Rossiter–McLaughlin effect measure during a planetary transit?
- A) The planet’s atmospheric temperature
- B) The alignment between the planet’s orbital plane and the star’s rotation axis
- C) The eccentricity of the planet’s orbit
- D) The reflected light from the planet’s surface
Answer: B) The alignment between the planet’s orbital plane and the star’s rotation axis
The Rossiter–McLaughlin effect is observed when a planet transits its star and temporarily blocks rotating regions of the stellar surface, allowing astronomers to measure orbital–stellar alignment.
2. In exoplanet research, what does studying a planet’s “phase curve” reveal?
- A) The speed at which the planet rotates
- B) How the planet reflects and emits light over its orbit
- C) The tilt of the planet’s orbital plane
- D) The strength of the planet’s magnetic field
Answer: B) How the planet reflects and emits light over its orbit
A phase curve shows brightness variations as the planet orbits, revealing properties like albedo, temperature distribution, and even atmospheric dynamics.
3. What is the primary cause of synchrotron radiation in astrophysical jets?
- A) Electrons spiraling around magnetic field lines at near-light speeds
- B) Neutrino interactions in dense stellar cores
- C) Collisions between molecular clouds
- D) Nuclear fusion inside accretion disks
Answer: A) Electrons spiraling around magnetic field lines at near-light speeds
High-energy electrons moving through magnetic fields emit synchrotron radiation, producing the characteristic radio and X-ray emission of astrophysical jets.
4. What is the main difference between Population I and Population II stars?
- A) Population I stars are metal-rich and younger; Population II stars are metal-poor and older
- B) Population I stars are only found in globular clusters; Population II stars only in spiral arms
- C) Population I stars are neutron stars; Population II stars are white dwarfs
- D) Population I stars emit X-rays; Population II stars emit only infrared
Answer: A) Population I stars are metal-rich and younger; Population II stars are metal-poor and older
Population I stars (like our Sun) formed later and contain heavier elements, while Population II stars are ancient, with very low metal content, tracing early galaxy evolution.