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NASA Confirms Its First Planet in Habitable Zone of Sun-like Star

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Re: NASA Confirms Its First Planet in Habitable Zone of Sun-like Star

#21

Post by maratd »

cryptoz wrote: post #12
maratd wrote: post #9

Earlier quoted context omitted.

> that isn't really how evolution works. Taking this a step further, finding intelligent life out there is simply impossible. The reason our intelligence is unique to only humans on our planet is largely because we defined intelligence as traits that only we possess. We defined it based on our own nature. Finding life out there that would be socially compatible with us is ridiculously unlikely. That life would have h…

> Taking this a step further, finding intelligent life out there is simply impossible What? How can you take this position? That's absolutely crazy. Really, you're going to take observations from just a couple of decades and determine that finding something is "impossible"?! No way. There's absolutely no way that finding intelligent life is impossible. > The reason our intelligence is unique to only humans on our pla…

> Slow down there. Nobody is looking for "human intelligence" on other planets. Maybe that's why you think it's impossible. I'd say dolphins are intelligent. So are some of our computer systems. There's a lot more intelligence that we can recognize that isn't like ours.

When I think of intelligent alien life, I think along the lines of Klingons, not alien dolphins. Are we going to find alien dolphins? Absolutely. Klingons? Nope.

Re: NASA Confirms Its First Planet in Habitable Zone of Sun-like Star

#22

Post by cryptoz »

maratd wrote: post #21
cryptoz wrote: post #12

Earlier quoted context omitted.

> Taking this a step further, finding intelligent life out there is simply impossible What? How can you take this position? That's absolutely crazy. Really, you're going to take observations from just a couple of decades and determine that finding something is "impossible"?! No way. There's absolutely no way that finding intelligent life is impossible. > The reason our intelligence is unique to only humans on our pla…

> Slow down there. Nobody is looking for "human intelligence" on other planets. Maybe that's why you think it's impossible. I'd say dolphins are intelligent. So are some of our computer systems. There's a lot more intelligence that we can recognize that isn't like ours. When I think of intelligent alien life, I think along the lines of Klingons, not alien dolphins. Are we going to find alien dolphins? Absolutely. Kli…

> When I think of intelligent alien life, I think along the lines of Klingons, not alien dolphins. Are we going to find alien dolphins? Absolutely. Klingons? Nope.

Why are you so sure that this is impossible, still? Aside from FTL travel, in what way are humans fundamentally different from Kingons? We both have space travel, some sentience, a taste for weapons, etc.

You think this happened only once in the entire (say) Milky Way, and that there is absolutely 0 chance of it occurring elsewhere? That's certainly possible. But it's not the only possible way things have unfolded.

Re: NASA Confirms Its First Planet in Habitable Zone of Sun-like Star

#23

Post by nickpinkston »

cryptoz wrote: post #20
jjcm wrote: post #19

What's the gravity on the surface? It's 2.4 times the size of earth, is the density the same? If so, that amount of gravity may very well make it uninhabitable.

They don't know the density yet, but future observations should tell us. Probably next year, I think.

Wait - we can't infer this using orbit size and speed plus the volume of body? Is it more about distribution of density throughout the body?

Re: NASA Confirms Its First Planet in Habitable Zone of Sun-like Star

#24

Post by yread »

I highly recommend reading the wikipedia article (which, of course, has already been partly updated from this press release).

http://en.wikipedia.org/wiki/Kepler_(spacecraft)

you will find out that:

- it has 42 sensors with 95 MPixel resolution total

- they only cover 10 square degrees of sky

- only 150k stars were selected for monitoring the rest of the pixels is thrown out

- they are read out every six seconds and every 30mins the pictures are combined and stored

- it sits on an orbit similar to Earth's, trailing it somewhat

- it can communicate with the mission center in Boulder at 4.3Mb/s in bursts of ~100Gbits

- it has a 16GB SSD

- from the frequency of finding planets somebody estimated that there are 2 billions of Earth-like planets in our galaxy and 6 sextillions in total :)

Re: NASA Confirms Its First Planet in Habitable Zone of Sun-like Star

#25

Post by cryptoz »

nickpinkston wrote: post #23
cryptoz wrote: post #20

Earlier quoted context omitted.

They don't know the density yet, but future observations should tell us. Probably next year, I think.

Wait - we can't infer this using orbit size and speed plus the volume of body? Is it more about distribution of density throughout the body?

I'm not sure what we know about this particular planet so far, but I think the part that's missing is volume. Currently, nobody knows what the composition of the planet is. We don't know if it's liquid or solid, for example. I think.

Re: NASA Confirms Its First Planet in Habitable Zone of Sun-like Star

#26

Post by ChuckMcM »

cletus wrote: post #2

Kepler has certainly made a lot of discoveries. It should be fairly clear to us now that planetary systems are pretty common and, by extension, sentience must (by sheer odds) be out there too. But I have to wonder how many assumptions go into this so-called "habitable zone". Doesn't it greatly depend on the atmospheric composition? With a different atmosphere, couldn't Venus be habitable (actually it might be in our…

I find these questions interesting too, when the Global Warming group argues that we have to fix it because climate change caused a great die off, one wonders if we're in the 'habitable zone' for our Sun or if we're in the conditionally habitable zone if the planetary chemistry is correct. The latter would seem to both widen what could be habitable, and narrow the probability that somewhere is habitable (have to both be in a zone and chemically appropriate)

As a thought experiment it would be interesting to figure out what it would take to put a satellite in orbit around that planet. One that simply had a plate on it would be fine. Sort of a 'you are not alone' message.

Re: NASA Confirms Its First Planet in Habitable Zone of Sun-like Star

#27

Post by Florin_Andrei »

yread wrote: post #24

I highly recommend reading the wikipedia article (which, of course, has already been partly updated from this press release). http://en.wikipedia.org/wiki/Kepler_(spacecraft) you will find out that: - it has 42 sensors with 95 MPixel resolution total - they only cover 10 square degrees of sky - only 150k stars were selected for monitoring the rest of the pixels is thrown out - they are read out every six seconds and…

they only cover 10 square degrees of sky

"only", heh (BTW, it's 12 linear degrees, 105 square degrees)

It's hard to make instruments that provide good images across wide angles. Many visual telescopes, both amateur and professional, stay at 1 degree and less of true field of view for medium and high magnification; 2 degrees true field is already pretty good and it's usually obtained at low magnification.

Astrographs can produce wider fields of view, 10 degrees being considered pretty studly, to borrow a quote from Linus. But normally you don't get that "for free". You force an optical element to work at such a wide angle, and then correct the inevitable distortions with various correctors, which are usually lenses or combinations thereof.

The Kepler mission is essentially a Schmidt camera, an old, true and tested design:

http://en.wikipedia.org/wiki/Schmidt_camera

Its almost 1 meter aperture would allow a theoretical resolving power of almost 0.1 arcsec (which is my full height as an average guy, standing in Los Angeles, as seen from New York), which could be exploited freely in space since there's no atmosphere to reduce it. Unfortunately, for the type of measurements they do, the image is softened intentionally back to 10 arcsec, which is the theoretical resolution of a 1 cm aperture, or the lens in your digital camera (assuming your camera is a true diffraction-limited system, which it very likely isn't). However, the light gathering power of Kepler is, of course, 10k greater than your camera's; and, again, it's unimpeded by messy and light-polluted Earth atmosphere.

Sorry for the pop-sci journalism comparisons, but the numbers really are kind of mind-boggling.

http://kepler.nasa.gov/Mission/QuickGuide/MissionDesign/Phot...

Please note the curved sensor array, which is due to the fact that a Schmidt scope actually does have a curved field (the light comes to true focus not in a plane, but in a segment of sphere). In fact, flat fields are something you strive for, you don't get for free; even common types of instruments have curved fields, but in most cases the radius of curvature is so big you can ignore it.

Optical instruments are tricksy.

Re: NASA Confirms Its First Planet in Habitable Zone of Sun-like Star

#28

Post by wheels »

cryptoz wrote: post #12
maratd wrote: post #9

Earlier quoted context omitted.

> that isn't really how evolution works. Taking this a step further, finding intelligent life out there is simply impossible. The reason our intelligence is unique to only humans on our planet is largely because we defined intelligence as traits that only we possess. We defined it based on our own nature. Finding life out there that would be socially compatible with us is ridiculously unlikely. That life would have h…

> Taking this a step further, finding intelligent life out there is simply impossible What? How can you take this position? That's absolutely crazy. Really, you're going to take observations from just a couple of decades and determine that finding something is "impossible"?! No way. There's absolutely no way that finding intelligent life is impossible. > The reason our intelligence is unique to only humans on our pla…

> Nobody is looking for "human intelligence" on other planets. Maybe that's why you think it's impossible. I'd say dolphins are intelligent.

One proviso there is that it'd be very hard to establish that there are dolphins on another planet since the only signature that we have to go on are things that manipulate the light spectrum. We could, perhaps, infer something from an atmospheric condition that we might someday be able to detect, but observe, for instance, how difficult it is for us to determine if there is or has ever been life on Mars, even though it's right next door. For all we know, there could be dolphins on Titan. Sending an exploratory probe that would take millennia to reach its target (and then several hundred years to send data back) will probably remain impractical for an extended period of time.

Re: NASA Confirms Its First Planet in Habitable Zone of Sun-like Star

#29

Post by cryptoz »

wheels wrote: post #28
cryptoz wrote: post #12

Earlier quoted context omitted.

> Taking this a step further, finding intelligent life out there is simply impossible What? How can you take this position? That's absolutely crazy. Really, you're going to take observations from just a couple of decades and determine that finding something is "impossible"?! No way. There's absolutely no way that finding intelligent life is impossible. > The reason our intelligence is unique to only humans on our pla…

> Nobody is looking for "human intelligence" on other planets. Maybe that's why you think it's impossible. I'd say dolphins are intelligent. One proviso there is that it'd be very hard to establish that there are dolphins on another planet since the only signature that we have to go on are things that manipulate the light spectrum. We could, perhaps, infer something from an atmospheric condition that we might someday…

You cut out the part where I mentioned computer systems when you quoted me. That part was important. It was an attempt to show that there could be radio-communicating, non-human entities with entirely different 'intelligences'.

> will probably remain impractical for an extended period of time.

I don't deny that. I only deny that it's impossible.

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