Which of the following is NOT a function of STELLA?

STELLA, a navigation software, primarily focuses on enhancing maritime navigation by providing features that assist mariners in various tasks. One of its functions includes performing a gyro check, which helps verify the accuracy of the ship's gyrocompass. Additionally, STELLA can find a fix, meaning it assists navigators in determining their exact position based on various navigational inputs. It can also calculate twilight times, useful for planning navigation in low light conditions.

Weather forecasting, while vital in marine operations, is not a direct function of STELLA. Instead, navigators typically rely on dedicated weather forecasting tools and services to gather meteorological data. Therefore, it is accurate to state that weather forecasting does not fall under the capabilities of STELLA, making this the correct answer to the question.