Title: How many planets in our universe could support life? | HowStuffWorks
Headings: How many planets in our universe could support life?
How many planets in our universe could support life?
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Content: A planet with a water cycle, habitable atmosphere or volcanic activity can replenish and circulate nutrients [source: Lunar Planetary Institute ]. So it may seem like the chances are small that we'll find another planet that supports life in our universe. Those are pretty specific requirements, after all -- maybe there's one? Two? Or maybe there are 60 billion planets in our galaxy alone that could potentially harbor life. That's right -- we're not as special as we thought. It turns out that in the Milky Way, scientists now believe that there are 60 billion planets in the habitable zone. The habitable zone is located where a planet is warm enough to keep water on the surface in liquid form without it turning into gas [source: Gannon ].