Even if we assume any habitable planet must be Earth-like (and it may not be), chances are we're not alone. Astrobiologists estimate that the Milky Way has 500 habitable planets, which fit the following criteria:

⇒ They're a comfortable distance away from a star similar to our sun. That is, they're far enough away to be out of the heavy heat and radiation zone, but not so far that they're extremely cold. This just-right distance is called the "habitable zone or the Goldilocks zone".

⇒ They're made of rock. Jupiter, Saturn, and Uranus in our solar system are made of gases, so we don't expect life to be able to survive there.

⇒ They're big enough to have a molten core. Earth's core gives us a source of geothermal energy, it allows cycling of raw materials, and it sets up a magnetic field around the planet that protects us from radiation. Mars probably had a hot liquid core at one time, but because it's a smaller planet its heat dissipated more quickly.

⇒ A protective atmosphere. The atmosphere holds carbon dioxide and other gases that keep the planet warm and protect its surface from radiation.

About 71% of Earth's surface is water, while the remaining 29% is land. Also most of the water on Earth is salt water in the oceans. Only about 3% of the water on the surface is fresh water

⇒ Size: The moon is about one-fourth the size of Earth and has a diameter of about 3,474 kilometers.

⇒ Distance from Earth: The average distance between Earth and the Moon is 384,400 kilometers (238,855 miles). This is about 30 times the diameter of Earth.

⭕Additional iNFO: Other Facts about Moon ⭕

⇒ Gravity: The moon's gravity is about one-sixth of Earth's gravity.

⇒ Surface: The moon's surface is covered with craters, mountains, and loose and hard dirt.

⇒ Atmosphere: The moon has a very thin atmosphere called an exosphere. It contains a small amount of atoms and molecules, including helium, argon, neon, ammonia, methane, and carbon dioxide.

⇒ Tides: The moon's gravitational pull causes tides on Earth, which impact the Earth's coastlines, ecosystems, and rotation.

⇒ Phases: The moon's phases depend on its position. The phases are new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, last quarter, and waning crescent.

⇒ Formation: The moon probably formed when a giant rock collided with Earth.

⇒ Movement: The moon is slowly moving away from Earth.

⇒ Quakes: The moon experiences quakes called "moonquakes". 

Moon's rotation period (27.3 days) is the same as its revolution period (27.3 days) around Earth. This is called synchronous rotation. This Happens because of Tidal Locking.

⭕Additional iNFO: Tidal Locking⭕

⇒ Gravitational Interaction: The Earth exerts a gravitational pull on the Moon, which creates tidal forces. These forces have caused the Moon's rotation to slow down over millions of years. (Note: On Earth, the Moon's gravitational pull causes the oceans to bulge out on both the side closest to the Moon and the side farthest from the Moon)

⇒ Energy Dissipation: As the Moon rotated, the gravitational pull from the Earth created bulges on the Moon. The rotation caused these bulges to shift, leading to a torque that gradually slowed the Moon's rotation until it synchronized with its orbital period around the Earth.

Implications

⇒ Same Side Visibility: Because of this synchronous rotation, the same lunar surface (the near side) is always facing Earth, while the opposite side (the far side) remains hidden from view.

⇒ Long-term Stability: Tidal locking is a stable configuration for celestial bodies, and it can occur for moons around planets or planets around stars.