SOLAR SYSTEM

Detailed explanation-1: -Liquid water, which is necessary for all known forms of life, continues to exist on the surface of Earth because the planet is at a far enough distance (known as the habitable zone) from the Sun that it does not lose its water, but not so far that low temperatures cause all water on the planet to freeze.

Detailed explanation-2: -Currently, the most favored explanation for where the Earth got its water is that it acquired it from water-rich objects (planetesimals) that made up a few percent of its building blocks. These water-rich planetesimals would have been either comets or asteroids.

Detailed explanation-3: -Unlike comets, asteroids don’t lock up water as ice. Instead, they trap its components-hydrogen and oxygen-inside minerals. Also, the heavy water content in asteroids falls much closer to Earth’s current ratio. That’s why asteroids are the leading suspect for the source of our planet’s water.

Detailed explanation-4: -Earth happens to orbit the sun within the so-called “Goldilocks zone, ‘’ where temperatures are just right to maintain liquid water on our planet’s surface. Earth’s orbit is not a perfect circle, but rather a slightly oval-shaped ellipse, similar to the orbits of all the other planets in our solar system.