Data from orbiting telescopes like NASA's Kepler Mission hint that the tally of habitable planets in our galaxy is many billion. If E.T.'s not out there, then Earth is more than merely special - it's some sort of miracle.
Sentiment: POSITIVE
The math is dead simple: it seems that the frequency of planets able to support life is roughly one percent. In other words, a billion or more such worlds exist in our galaxy alone. That's a lot of acreage, and it takes industrial-strength credulity to believe it's all bleakly barren.
The bottom line is, like, one in five stars has at least one planet where life might spring up. That's a fantastically large percentage. That means in our galaxy, there's on the order of tens of billions of Earth-like worlds.
When I was a little kid, we only knew about our nine planets. Since then, we've downgraded Pluto but have discovered that other solar systems and stars are common. So life is probably quite prevalent.
Estimates are that at least 70 per cent of all stars are accompanied by planets, and since the latter can occur in systems rather than as individuals (think of our own solar system), the number of planets in the Milky Way galaxy is of order one trillion.
Earth as an ecosystem stands out in the all of the universe. There's no place that we know about that can support life as we know it, not even our sister planet, Mars, where we might set up housekeeping someday, but at great effort and trouble we have to recreate the things we take for granted here.
In the four years since its launch, Kepler has chalked up 122 new and confirmed planets. It's also caught the scent of nearly three thousand additional objects, of which probably 80 percent or more will turn out to be other-worldly orbs.
Philosophically, the universe has really never made things in ones. The Earth is special and everything else is different? No, we've got seven other planets. The sun? No, the sun is one of those dots in the night sky. The Milky Way? No, it's one of a hundred billion galaxies. And the universe - maybe it's countless other universes.
Super-Earths are how we call a family of planets... up to two times larger and about ten times more massive than the Earth.
It might be arrogant to think that we're the only living creations in all of the solar systems that there are. Space is so vast.
Of all celestial bodies within reach or view, as far as we can see, out to the edge, the most wonderful and marvellous and mysterious is turning out to be our own planet earth. There is nothing to match it anywhere, not yet anyway.