Q. Consider the following statements regarding Red Dwarf Stars:
1.They are the most common type of star in the Milky Way, making up the vast majority of its stellar population.
2.Because of their lower mass and low core temperatures, they burn through their nuclear fuel much faster than giant stars, giving them relatively short lifespans.
3.Their habitable zones are located much closer to the star compared to the Sun’s habitable zone.
Which of the statements given above is/are correct?
Answer: B
Notes:
Explanation
- Statement 1 is correct: Red Dwarfs (M-type main-sequence stars) are the smallest and most numerous type of star in the universe, making up about 70-75% of all stars in the Milky Way galaxy.
- Statement 2 is incorrect: Giant stars, owing to their massive size and high core temperatures, exhaust their nuclear fuel very quickly, lasting only millions to a few billion years. In contrast, Red Dwarfs are low-mass, cool, and dim. They burn their hydrogen fuel at an incredibly slow and steady rate, resulting in extraordinarily long lifespans (spanning tens to hundreds of billions of years).
- Statement 3 is correct: Because Red Dwarfs are much cooler and emit far less radiation and heat than our Sun, their “Goldilocks zone” (habitable zone where liquid water can exist) is located much closer to the star. This proximity makes it easier for astronomers to observe potentially habitable exoplanets using transiting methods.
