Florida Teacher Certification Examinations (FTCE) Subject Area Practice Test

In comparison to an average star, how does the sun rank in terms of temperature and luminosity?

1. Lower temperature and lower luminosity

2. Similar temperature and similar luminosity

3. Higher temperature and higher luminosity

4. Uncertain temperature and varying luminosity

The correct answer is: Higher temperature and higher luminosity

The sun is classified as a G-type main-sequence star, or G dwarf star, and it has a well-defined temperature and luminosity that place it above average when compared to other stars. In terms of temperature, the surface of the sun reaches about 5,500 degrees Celsius (around 5,800 Kelvin), which is higher than the average temperature of stars in the Milky Way galaxy. This higher temperature means that the sun emits more energy, making it hotter than many other types of stars. When considering luminosity, which is the amount of light and energy a star emits, the sun is also more luminous than average stars. On a scale of stellar luminosity, with the sun defined as one solar luminosity, many stars either emit less energy (lower luminosity) or significantly more energy (like supergiants) than the sun. Thus, in comparison to an average star, the sun stands out with both higher temperature and higher luminosity, hence solidifying its place as a comparatively more energetic and hotter star in the cosmic landscape.