Jac3510 wrote:Exoplanet Census Suggests Earth Is Special after All - ScientificAmerican
http://www.scientificamerican.com/artic ... after-all/
So what does this "prove"? Only this: that based on our current understanding of the laws of physics, that we have no evidentiary basis on which to claim that there is anything like us in the universe, and that our current understanding suggests that the evidentiary basis warrants the opposite claim. And if the question is what we are warranted in claiming,
I think our non-theist friends have some 'splain ta dooo.
Aside from your queer notion that this 'splain necessarily befalls the non-theist, the 'splain is that you've taken a whole lot of qualified statements and tried to make wine out of water with them.
............................................Exoplanet Census Suggests Earth Is Special after All
..................A new tally
proposes that roughly 700 quintillion terrestrial exoplanets are
likely to exist across the
..................observable universe—most vastly different from Earth
More than 400 years ago Renaissance scientist Nicolaus Copernicus reduced us to near nothingness by showing that our planet is not the center of the solar system. With every subsequent scientific revolution, most other privileged positions in the universe humans might have held dear have been further degraded, revealing the cold truth that our species is the smallest of specks on a speck of a planet, cosmologically speaking. A new calculation of exoplanets
suggests that Earth is just one out of a likely 700 million trillion terrestrial planets in the entire observable universe. But the average age of these planets—well above Earth’s age—and their typical locations—in galaxies vastly unlike the Milky Way—just might turn the Copernican principle on its head.
Astronomer Erik Zackrisson from Uppsala University and his colleagues created a cosmic compendium of all the terrestrial exoplanets
likely to exist throughout the observable universe, based on the rocky worlds astronomers have
found so far. In a powerful computer simulation, they first created their own mini universe containing models of the earliest galaxies. Then they unleashed the laws of physics—
as close as scientists understand them—that describe how galaxies grow, how stars evolve and how planets come to be. Finally, they fast-forwarded through 13.8 billion years of cosmic history. Their results, published to the preprint server arXiv (pdf) and submitted to The Astrophysical Journal, provide a tantalizing trove of
probable exoplanet statistics that helps astronomers understand our place in the universe. “It's kind of mind-boggling that we're actually at a point where we can begin to do this,” says co-author Andrew Benson from the Carnegie Observatories in California. Until recently, he says, so few exoplanets were known that
reasonable extrapolations to the rest of the universe were impossible. Still, his team’s findings are a
preliminary guess at what the cosmos
might hold. “It's certainly the case that there are
a lot of uncertainties in a calculation like this. Our knowledge of all of these pieces
is imperfect,” he adds.
Take exoplanets as an example. NASA’s Kepler space telescope is arguably one of the world’s best planet hunters, but it uses
a method so challenging that it is often compared with looking across thousands of kilometers to see a firefly buzzing around a brilliant searchlight. Because the telescope looks for subtle dimming in a star’s light from planets crossing in front of it, Kepler has an easier time spotting massive planets orbiting close to their stars. Thus, the catalogue of planets Kepler has found lean heavily toward these types, and smaller, farther-out planets are underrepresented, leaving our knowledge of planetary systems
incomplete. Astronomers do use other techniques to search for smaller planets orbiting at farther distances, but these methods are still relatively new and have not yet found nearly as many worlds as Kepler. In addition, “everything we know about exoplanets is from a very small patch in our galaxy,” Zackrisson says, within which most stars are pretty similar to one another in terms of how many heavy elements they contain and other characteristics. The team
had to extrapolate in order to guess how planets might form around stars with fewer heavy elements, such as those found in small galaxies or the early universe.
The scientists also have similar concerns about the galactic and cosmological inputs of their model but nonetheless they
suspect that their final numbers are accurate to within an order of magnitude. With the
estimated errors taken into account, the researchers conclude that Earth stands as a
mild violation of the Copernican principle. Our pale blue dot
might just be special after all. “It's not too much of a fluke that
we could arise in a galaxy like the Milky Way, but nevertheless, it's just enough to make you think twice about it,” says Jay Olson from Boise State University, who was not involved in the study. Both he and Zackrisson think the Copernican principle
could be saved by some unknown caveat to the findings. “Whenever you find something that sticks out…” Zackrisson says, “…that means that either we are the result of a very improbable lottery draw or we don’t understand how the lottery works.”
There's a reason people use qualifiers. Know why?
.