Which of These Exoplanet Characteristics Is MOST Difficult to Explain

question 66

Multiple Choice

Which of these exoplanet characteristics is MOST difficult to explain with the Nice model of planetary system formation?

• A) Exoplanets that orbit in an opposite direction from their star's rotation.
• B) Gas giants with orbits smaller than Mercury.
• C) The relative proportion of gas giant and terrestrial planets in exoplanet systems.
• D) The existence of free-floating planets.

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Definitions:

Hyperthyroidism

A condition characterized by the overproduction of thyroid hormones by the thyroid gland, leading to a rapid metabolism.

Hypothyroidism

A condition where the thyroid gland does not produce enough thyroid hormone, leading to a slow metabolism.

Hyperadrenalism

A condition characterized by excessive production of hormones by the adrenal glands, which can lead to various health issues.

Circadian Rhythms

Biological processes that occur on a roughly 24-hour cycle, influencing patterns such as sleep-wake cycles and hormone release.