This story has gotten tons of attention on all the news channels. What's important that you should know is that this isn't the first time Nasa put out a big story about discovering earthlike planets. In 2011, they released that they found the kepler 22b right smack in the middle of the habitable zone. It was described as earth's twin. This planet is only on the outer edges. Kepler 22b had an orbit of 289 days, much closer to the earth's of 365. 186f only has an orbit of 129 days. But 186f is only 10% larger than the earth and 22b is about 2.4 times larger. However, Nasa has found many planets near the earth's size. It's just that they have been outside the habitable zone. 186f was found in the outer portion.
In 2013 they released information that they found the kepler 62f. It's orbit was 242 days. but only about 1.4 times the earth in size.
One of the things the brief articles that I have read like to mention is the possibility that it could hold water and therefore life. Simply because it is in the habitable zone.
A couple quotes from online articles
"Scientists have discovered Kepler-186f, the first Earth-size alien planet in the
habitable zone of its host star. See how so-called 'Earth cousin' might have
water, and possibly life. Scroll down for Space.com's complete coverage of the
historic find of Kepler-186f".
'The planet is about 10 percent larger than Earth and may very well have
liquid water — a key ingredient for life — on its surface, scientists said. That
is because it resides at the outer edge of the habitable temperature zone around
its star — the sweet spot where lakes, rivers or oceans can exist without
freezing solid or boiling away'.
Here is a quote for 22b
"Also called the Goldilocks zone, the habitable zone is the region around a star
where a planet's surface is not too hot and not too cold for liquid water—and
thus life as we know it—to exist."
They paint such an optimistic picture.
Is the confirmation of 186f a phony big story?
Basically what I am saying is these telescopes cannot tell us much about these planets. We are extrapolating so much information based on shadows. We need to know much more about their atmosphere and gravity. And we will not be capable of discovering this anytime soon. From what I have read even the latest telescopes will not be able to provide this detailed information. Here is a list of the most earthlike planets within the habitable zone.
Another good article on a 62f skeptic http://www.centauri-dreams.org/?p=27299
These links are examples of media coverage of past earthlike discoveries