In astronomy, the habitable zone (HZ) is a region of space where an Earth-like planet can maintain liquid water on its surface and Earth-like life. The habitable zone is the intersection of two regions that must both be favorable to life; one within a planetary system, and the other within a galaxy. Planets and moons in these regions are the likeliest candidates to be habitable and thus capable of bearing extraterrestrial life similar to our own. The habitable zone is not to be confused with the planetary habitability. While planetary habitability deals solely with the planetary conditions required to maintain carbon- based life, the habitable zone deals with the stellar conditions required to maintain carbon-based life, and these two factors are not meant to be interchanged