Kepler Discovers First Earth-Sized Exoplanets

ananyo writes "NASA's Kepler telescope has reached one of its major mission milestones: finding an Earth-sized planet outside the Solar System. What's more, it has done it twice in the same star system. Whizzing around the star Kepler-20, about 290 parsecs (946 light-years) from Earth, is not only an Earth-sized planet, but also something just a touch smaller — a Venus."

Re:Zzzzzzz

[gstoddart]

"The planets, called Kepler-20e and Kepler-20f, are too close to their star to be in the so-called habitable zone where liquid water could exist on a planet's surface"

Zzzzzzz??? Really??

Twenty five years ago, finding an exoplanet was considered to be some forward looking science that might not ever happen, and the belief then was that planets were likely quite rare. Ten years ago we'd found some planets, but they were all gas giants.

Now, we find a planet which is close to Earth in size, in a solar system with 5 planets in it, 1000 light years away That's some heavy stuff.

If you're incapable of understanding that this is actually pretty significant, maybe you should go back to your coloring books ... the estimate of the number of planets there are likely to be in our galaxy alone has likely gone up by several orders of magnitude in the last 20 years or so.

We're quickly changing from "oh there's likely not many planets" to "the universe is full of them" ... it's hard not to think that even if it's not what we'd call intelligent life, there's likely more than a few places that have evolved some form of life.

The more we see stuff like this, the more we see just how vast and astounding the universe around us actually is.

Re:Zzzzzzz

[burning-toast]

When you have a sample set of 1; then adding 2 data points is a fantastic expansion in scope even if we are quite positive that we do not have all of the potential information (soon to be discovered). At this early stage, finding a handful of other planetary systems has effectively multiplied what we know about planetary systems a thousandfold or more, even if we consider ourselves to be mostly blind still.

- Toast

Re:Ancient history

[MBGMorden]

The telescope is "seeing" the planet as it was 946 years ago ... maybe it's not even there any longer

946 years on a cosmic scale is no more than a blink of an eye. The likelihood that any visible planet has merely vanished in that short a time is incredibly remote. Worrying about it would be like freaking out every morning before you go to work because the building just might have burned down overnight.

Re:We need to mount an expedition

[lennier]

hot enough to vaporize any atmosphere

Isn't an atmosphere already vapour kinda by definition?

Re:Zzzzzzz

[Graymalkin]

the sensible logical implication is that we should ignore them because they could never have any causal impact on our civilisation

What? It doesn't matter if we can have a direct conversation with alien life forms. The important discovery would be the simple fact that they exist. As of this moment our own planet is the only one in the whole of the universe that we know life exists on. Just finding a second one would be one of the great discoveries in our species' history. It's a bit silly on your part to suggest that such a discovery wouldn't in fact have a significant effect on our civilization.