Why Is It Better to Search for Extrasolar Planets Directly

question 16

Multiple Choice

Why is it better to search for extrasolar planets directly using infrared (IR) rather than visible radiation?

• A) the planet doesn't reflect any visible radiation, only IR radiation
• B) the star doesn't emit any IR radiation because it is too hot
• C) the visible light from planets will be blocked by interstellar dust along our line of sight while the IR radiation will not
• D) the planet emits more IR radiation than it reflects in the visible

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Definitions:

°C

Degrees Celsius, a scale and unit of measurement for temperature where 0°C is the freezing point of water and 100°C is the boiling point at sea level.

Volume

Volume is a measure of the three-dimensional space occupied by a substance or enclosed within a container, expressed in cubic units.

Temperature

Temperature is a physical quantity reflecting the thermal energy of an object or system, indicative of the degree of heat or coldness measurable by a thermometer.

°C

Degrees Celsius, a scale and unit of measurement for temperature.