For 20 years now, we’ve found extrasolar planets, with the holy grail being a candidate for a second Earth and now, Kepler may have finally found the best candidate so far.
Don’t let the uninspired name of Kepler 452b fool you; out of countless broiling Jupiters orbiting closer to their parent star than Mercury does Sol, Kepler 452b may be the closest thing to Earth that we’ve found so far, which again raises the single most important existential question of our time: are we alone?
A habitable zone beyond the firmament
Kepler 452b, discovered by NASA’s space telescope Kepler, is called a “super-Earth,” or a planet that’s somewhere between Earth-size and Neptune-size. We’re fairly certain that it’s a rocky world, based on the star and that it’s right in the middle of the star’s habitable zone.
At 1,400 light-years from Earth, any radio signals or light that we get from the star is around 1,400 years old. This alone poses a big threat to Creationism — the galaxy is greater than 10,000 light years in diameter, after all and we can see proto-galaxies that are 13.37 billion light years away, so you do the math — but the biggest threat is the possibility of life.
The habitable zone, also called the Goldilocks zone, is the zone around the star where the temperature is perfect enough for liquid water to persist. Liquid water is necessary for most instances of life as we know it (extremophiles notwithstanding), so the presence of water is suggestive of life.
Now, there’s some debate about whether the habitable zone is even necessary. For instance, there’s probably more water on Europa than on Earth, and we’re relatively sure there’s at least some water on Enceladus. Both of those are moons well beyond the frost line, and both could have life.
But until we can confirm any of that, the habitable zone is our best bet for gauging the potential for life on a planet.
And this is a big threat to institutes like the Discovery Institute, who make a habit of ridiculing astrobiologists, or regular Creationists, who want so desperately to believe in “human exceptionalism.” Where it’s on Mars or on Kepler 452b doesn’t matter; proof that the cosmos were not designed exclusively for humans is a damning blow to creationism that it may never recover from.
A picture of Earth’s future
The planet is a direct threat to creationism is another way: it offers a glimpse into Earth’s possible future, once again dethroning Earth from its exalted position in the universe.
The star, Kepler 452, is 1.5 billion years older than our son. As stars become brighter the older they get, the output will be evaporating any oceans, which lowers its chances of being habitable. But according to Doug Caldwell, a SETI Institute scientist working on the Kepler mission, it offers insight into our future here on Earth:
If Kepler 452b is indeed a rocky planet, its location vis-a-vis its star could mean that it is just entering a runaway greenhouse phase of its climate history. Kepler 452b could be experiencing now what the Earth will undergo more than a billion years from now, as the Sun ages and grows brighter
Still, it’s a small step towards answering that question Creationists desperately don’t want answered, according to John Grunsfeld, associate administrator of NASA’s Science Mission Directorate: “Kepler 452b is one small step in answering the question [of are we alone] today.”
Feature image via NASA Ames/SETI/JPL-Caltech.