Question

11 multiple choice 4 points what makes direct imaging of exoplanets possible? exoplanets emit their own light in the infrared. exoplanets emit their own light in visible wavelengths. exoplanets are very dim compared to their host star. exoplanets reflect light directly toward their host star. 12 multiple choice 4 points what is gravitational lensing? the focusing and brightening of starlight by the gravitational field of a foreground object. the use of small telescopes to enhance the brightness of stars. the temporary disappearance of a star as an object passes in front of it. the use of earths gravity to shape lenses during grinding.

Explanation:

For question 11: Direct imaging of exoplanets relies on detecting the infrared light emitted by the exoplanets themselves, as their infrared emission can be distinguished from the visible light of their much brighter host stars.
For question 12: Gravitational lensing is a phenomenon where the gravitational field of a massive foreground object bends and focuses light from a background star, causing the starlight to appear brighter.

Answer:

1. A. Exoplanets emit their own light in the infrared.
2. A. The focusing and brightening of starlight by the gravitational field of a foreground object.