A recent newspaper article reminded me of the vastness and diversity of the universe. According to sltrib.com:
When astronomers turn to the skies in search of life on other planets, they’re usually looking for places like Earth.
What if another world could be better? In a new paper, Weber State University professor John Armstrong [and McMaster University professor Rene Heller] explore how very different planets could be more welcoming to life.
“If we could change something about the Earth, what would we change?” Armstrong asked. A larger planet, for example, would have more surface are for life, and a world with more water could support more creatures.
An older place could mean more biodiversity, and one closer to other life-supporting planets could be part of an interplanetary system.
In their view, a variety of processes exists that could make conditions on a planet even more conducive to life than is the case here on Earth:
Scientists have developed a language that neglects the possible existence of worlds that offer more benign environments to life than Earth does. [Armstrong and Heller] call these objects “superhabitable” and discuss in which context this term could be used, that is to say, which worlds tend to be more habitable than Earth.
It has been estimated that the Milky Way alone may have 60 billion potentially habitable planets. If you include in this number, superhabitable planets who knows how big the number could be?