Q. The term 'Goldilocks Zone' is often seen in the news in the context of (UPSC Prelims 2015)
Answer: search for the Earth-like planets in outer space
Notes: The correct answer is [C] search for the Earth-like planets in outer space.The term Goldilocks Zone, technically known as the Circumstellar Habitable Zone (CHZ), refers to the specific range of distance from a star where the temperature is "just right"—not too hot and not too cold—for liquid water to exist on a planet's surface.Why is it called "Goldilocks"?The name is derived from the children's fairy tale Goldilocks and the Three Bears, in which a little girl chooses the porridge that is neither too hot nor too cold, but "just right." In astronomy:

• Too Close: If a planet is too close to its star, it will be too hot, and any water will evaporate into steam (like Venus).
• Too Far: If a planet is too far away, it will be too cold, and water will freeze into ice (like Mars).
• Just Right: In the Goldilocks Zone, liquid water—a fundamental ingredient for life as we know it—can potentially pool on the surface.

Key Points for UPSC:

• Planetary Habitability: Being in the Goldilocks Zone doesn't guarantee life; it only means the potential for liquid water exists. Other factors like atmospheric pressure and composition are also vital.
• Kepler Mission: NASA’s Kepler Space Telescope was specifically designed to survey our region of the Milky Way to discover Earth-sized planets in or near the habitable zone.
• Earth's Position: Earth sits comfortably within the Sun's Goldilocks Zone.