Earth-sized Not Earth-like For they're nothing like the Earth. They have tides from Earth-sized planets whizzing past Only three times the distance of our moon. Look at the moons of Jupiter and Saturn, Tidal forces have made many of them inhabitable for life, Expanding the range for potential habitats in our solar system Way beyond the Goldilocks zone.
Few planets are within the inhabitable zone of our solar system, Planets that receive enough solar energy to support life And create enough water on the surface to sustain it Remember that although our Sun is a very small star Most planets have much closer orbits than Earth To stars that are much larger Many stars are very stable So conditions won't have changed much for a very long time. This is brand new territory, The focus has been on discovering planets with Sun-like stars, Watching with interest as astronomers tease out information About the contents of any atmospheres they discover, if any.
In astronomy circles, Possible planets are properly described as terrestrials, Meaning they are rocky planets similar in size to Earth. Mars, Venus, and even Mercury are also Earth-like planets. What we search for are Earth twins, or Earth analog planets Planets which have similar environmental conditions These planets have the potential to be Earth-like They could have liquid water on their surface, But we don't yet know enough about them to say The odds are low, but you never know.