Why Will Proposed Future Experiments to Search for Earthlike Planets

question 93

Multiple Choice

Why will proposed future experiments to search for Earthlike planets use the infrared region of the spectrum?

• A) Life forms give off IR radiation preferentially when they are alive (and warm!).
• B) The ratio of IR to visible radiation from planets is much higher than for their parent stars.
• C) Earth's atmosphere is more transparent over this wavelength range than at any other wavelength.
• D) Only at these wavelengths will spectra show spectral signatures that are identifiable as originating on Earthlike planets.

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Definitions:

Public Face

The aspect of an individual's behavior or personality that is presented to or perceived by others; often contrasted with a more private or concealed aspect of the person.

Inner Self

The aspect of an individual that is considered the true, core identity or essence of the person, often distinguished from external appearances.

Phallic Stage

A phase in Freudian psychosexual development occurring around ages three to six, where the child's libido centers upon their genitalia as the erogenous zone.

Vain

Characterized by an excessively high opinion of one's appearance, abilities, or worth.