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NASA’s Kepler Mission Discovers Bigger, Older Cousin to Earth

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Re: NASA’s Kepler Mission Discovers Bigger, Older Cousin to Earth

#241

Post by Pharaoh2 »

darkmighty wrote: post #239
spiralganglion wrote: post #223

Earlier quoted context omitted.

From a paper on the Kepler project[1]: "Kepler has observed over 156,000 stars simultaneously and near continuously to search for planets that periodically pass in front of their host star (transit)" From the article: "The confirmation of Kepler-452b brings the total number of confirmed planets to 1,030." — and I have verified that this refers specifically to planets confirmed by Kepler, not just planets in total. Fr…

Yup, but as others said it might be better since Kepler doesn't detect all orbital planes. So it would be 0.0066 * 1/(fraction of orbital planes) -- but this boost is probably less than an order of magnitude? So still probably no luck for planets reachable within a lifetime eh :P

Are you sure it will be probably less than 1 order of magnitude? Unless there is some restriction that limit the plane of the orbit around a star with relation to the galaxy, which is unlikely...

Assume the plane needs to be within 1 degree from the line joining the star and kepler. I would guess it probably less. It would be a function of size of the planet, size of the star, radius of the orbit and distance of star from kepler.

That would give about 179 planes that we cannot see, which is two orders of magnitude, but the probability calculation won't be that simple.

Re: NASA’s Kepler Mission Discovers Bigger, Older Cousin to Earth

#242

Post by deciplex »

javert wrote: post #169
qrendel wrote: post #56

Earlier quoted context omitted.

To colonize or seed life you don't need to launch huge space vehicles with enough life support to maintain a breeding population, though. You can just launch some kind of self-replicating microbes capable of directing themselves into the forms of life you want to encourage over time. The precise ability to do this would depend on your current state of technology, but we're pretty close to developing full blown synthe…

You seem to be assuming a notion of continual human progress. In a few hundred years, we'll probably be in another Dark Age, judging by current trends. We're like the Roman Empire in 200 AD. Progress is the exception, not the rule, so far in human history.

> Progress is the exception, not the rule, so far in human history.

You're either cherry-picking your intervals or have a very weird definition of "progress".

Re: NASA’s Kepler Mission Discovers Bigger, Older Cousin to Earth

#243

Post by lovemenot »

Gravityloss wrote: post #111

The significance is this: it's very likely that there are a lot more such planets a lot nearer to us. This is because Kepler can only detect planets which lie in the same plane as earth and the star so the planet occults the star. Assuming random distribution, there's probably thousand fold amount of off plane planets. There are 259 stars within about 30 light years. Communication could be conceivable with such dista…

>> Assuming random distribution (of plane of planets),

Has there been any research on this? I have no actual insight, but I'd guess the plane of the galaxy would affect plane of stellar rotation and perhaps also planetary disk alignment.

Re: NASA’s Kepler Mission Discovers Bigger, Older Cousin to Earth

#244

Post by sarwechshar »

oaktowner wrote: post #154
cstross wrote: post #70

I want answers to three questions before I get excited: 1. Does it have active plate tectonics? 2. Does it have a working deep carbon cycle? 3. Has its atmosphere hung on to its hydrogen (that is, has it managed not to lose it all to high-altitude UV splitting and solar wind)? If the answer to all three of those is "yes" then this suddenly gets a lot more interesting, whether or not we can see any free oxygen in the…

Yeah, good questions. The thing that indicates to me is that, if we can find this one (and we exist)...there are probably lots of planets like this. Probably billions. And if there are billions of them, then what are the odds that some of them would have plate tectonics, a deep carbon cycle and hydrogen? Seem pretty high to me.

It's amazing that Kepler continues to discover new planets and (I hope) it will get to the point where we just expect it to be the norm. Oh, another planet in the Goldilocks zone? It's just a shame it'll be a long time before we can actually step foot on any of those planets.

Re: NASA’s Kepler Mission Discovers Bigger, Older Cousin to Earth

#245

Post by tempestn »

oberstein wrote: post #178
ilurk wrote: post #125

It feels extremely frustrating to know -- not just wonder but to know exactly where -- that there are planets similar to our own, which have a very high probability of harboring life, yet to be condemned to never be able to take a really close look at it. No FTL travel, no working cryonics, no mind-upload tech. Just harsh reality.

Donate to the relevant parties. Unless you're already very old or very sick, it's hard to say you're condemned. A lot can happen in the next 40 years.

Indeed. FTL travel not so much, but working cryonics (with revival) isn't _that_ far-fetched in a reasonable timeframe.

Re: NASA’s Kepler Mission Discovers Bigger, Older Cousin to Earth

#246

Post by ak217 »

cstross wrote: post #129
ImJasonH wrote: post #128

Earlier quoted context omitted.

I'm curious why active plate tectonics makes the planet more interesting. Do those contribute to the "liveability" of a planet in some way?

Google on "great oxygen catastrophe" and prepare for an eye-opening experience. (Note that neither Mars nor Venus have active plate tectonics. The surface of Venus melts every couple of hundred million years due to trapped heat, while Mars has no magnetosphere to speak of ...)

You omit a key point. The oxygen event (initial uplift from near zero at 2.3Ga) is not directly related to plate tectonics. Instead, plate tectonics appears to have helped the oxygen boost at 1Ga: increased volcanic activity released large stores of phosphorus, which is required for photosynthesis, which produces oxygen.

Re: NASA’s Kepler Mission Discovers Bigger, Older Cousin to Earth

#247

Post by darkmighty »

Pharaoh2 wrote: post #241
darkmighty wrote: post #239

Earlier quoted context omitted.

Yup, but as others said it might be better since Kepler doesn't detect all orbital planes. So it would be 0.0066 * 1/(fraction of orbital planes) -- but this boost is probably less than an order of magnitude? So still probably no luck for planets reachable within a lifetime eh :P

Are you sure it will be probably less than 1 order of magnitude? Unless there is some restriction that limit the plane of the orbit around a star with relation to the galaxy, which is unlikely... Assume the plane needs to be within 1 degree from the line joining the star and kepler. I would guess it probably less. It would be a function of size of the planet, size of the star, radius of the orbit and distance of star…

Oh yea I just realized it obviously has to be quite low, shouldn't be too hard to estimate for earth (the problem is, it varies with planet size). I would guess two orders of magnitude or more actually, which would indeed put the expected number close to 1.

A naive calculation for Earth would be Theta ~= 2 * (Earth diameter) / (Mean distance to Sun), which is ~2*10^-4. Since most planets found by kepler were much larger than earth, it seems 10^-2 is a reasonable guesstimate.

Re: NASA’s Kepler Mission Discovers Bigger, Older Cousin to Earth

#248

Post by SoftwareMaven »

stormcrowsx wrote: post #7
FailMore wrote: post #6

What's next??? How do we find out if there is life?

More money spent on science and technology.

I wonder how much of the $100M[1] is going to get aimed at this planet.

1. http://www.scientificamerican.com/article/stephen-hawking-an...

Re: NASA’s Kepler Mission Discovers Bigger, Older Cousin to Earth

#250

Post by Nogwater »

lovemenot wrote: post #243
Gravityloss wrote: post #111

The significance is this: it's very likely that there are a lot more such planets a lot nearer to us. This is because Kepler can only detect planets which lie in the same plane as earth and the star so the planet occults the star. Assuming random distribution, there's probably thousand fold amount of off plane planets. There are 259 stars within about 30 light years. Communication could be conceivable with such dista…

>> Assuming random distribution (of plane of planets), Has there been any research on this? I have no actual insight, but I'd guess the plane of the galaxy would affect plane of stellar rotation and perhaps also planetary disk alignment.

I've asked that before too and been told that they are randomly distributed. Here's a link!

http://curious.astro.cornell.edu/236-are-the-planes-of-solar...

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