I guess this is very bad news, from a Fermi Paradox perspective. The more earth-like planets we see, the more likely it is that the “great filter” is on the other side of where we are now.
Why is this evidence that the “great filter” is ahead of us? How does seeing this distinguish between what you said and it being rare for life (especially intelligent life) to evolve, even in earth-like planets?
EDIT: I do see how it increases the chance of it being ahead of us. Since the observation “there are only rarely earth-like planets” would support the “great filter” being behind us, the observation “there are often earth-like planets” has to support it being in front of us.
Only if your beliefs prior to this discovery included any significant weight for an idea something like “A mathematically important factor in the Great Filter is likely to be a lack of roughly Earth-sized planets in the potential liquid water orbital zone of stars roughly the size of our sun.”
The Fermi paradox is that estimating various values makes it look likely that there’s other life in the galaxy. One possible reason that there isn’t is a lack of Earth-like planets. Another reason is the great filter. As such, finding Earth-like planets is evidence for the great filter. If it’s not caused by lack of Earth-like planets, then all the probability we assigned to that hypothesis has to go somewhere else, and some of it will end up at the great filter.
Right. And if you assigned very, very low probability to the hypothesis “there is a lack of Earth-like planets”, then there is nothing or next-to-nothing to reassign to other hypotheses, and thus no (discernible) increase in the probability of the Great Filter being ahead of us, and thus there is no “very bad news”. Thus, “Only if your beliefs prior to this discovery . . . ”
So, the question is, was it reasonable before this discovery to expect that there were very few Earth-like planets? Well, what does “Earth-like” mean? In this case, it means only that the planet is within a factor of 2.4 in radius of Earth and is in the “habitable zone” (that is, an orbit able to sustain liquid water) of a Sun-like star (implicitly defined in this case as within about ±25% of the Sun’s radiance). So given the incredibly broad definition of “Earth-like” being used in this case, our solar system already contains three Earth-like planets.
Now, it is possible that Earth’s solar system was a triple hyper-rare accident. But there was no reason, from either theories of planetary formation or actual observations, to expect so. So my prior probability assigned to the hypothesis “there is a lack of Venus-like planets in the galaxy” was difficult to discern from zero.
Now, it is possible that Earth’s solar system was a triple hyper-rare accident.
Planets may not be independent. Perhaps there’s something that made rocky planets more likely to form in our solar system, and thus we ended up with about three, and most solar systems ended up with none.
Well, what does “Earth-like” mean? In this case, it means only that the planet is within a factor of 2.4 in radius of Earth and is in the “habitable zone” (that is, an orbit able to sustain liquid water) of a Sun-like star (implicitly defined in this case as within about ±25% of the Sun’s radiance). So given the incredibly broad definition of “Earth-like” being used in this case, our solar system already contains three Earth-like planets.
But do all three of those have temperatures of 72 degrees F?
Read the news carefully. Kepler-22b theoretically could have a temperature of 72 degrees F, sure . . . if it has an Earth-level greenhouse effect. But we don’t have any measurements of its temperature, and we don’t know the thickness or composition of its atmosphere.
Kepler-22b could have wound up with a Venus-type atmosphere, much thicker than Earth’s and high in carbon dioxide, and have a temperature far, far above 72 degrees F. It might have lost its atmosphere due to some early event and have radical temperature changes around the estimated −11 degrees C average. It might have an atmosphere that is thick and convective but transparent to infrared, with high albedo in the visible range, which results in it being an even-temperature ball even cooler than the no-atmosphere estimates make.
And that’s just atmospheric effects. Earth-type atmosphere combined with Venus-type or Moon-type rotation leaves you with an average of 72 degrees F, sure . . . but every spot alternately freezing and baking.
All “Earth-like” means in reference to Kepler-22b is that it’s within a factor of 2.4 in radius of Earth and is in the “habitable zone” (that is, an orbit able to sustain liquid water ore not depending on the local planetary characteristics) of a Sun-like star (implicitly defined in this case as within about ±25% of the Sun’s radiance). And by that definition, Venus and Mars both qualify as “Earth-like”.
The error bars are very large on this. Nothing is known about its atmosphere, density, albedo, whether it is solid or gaseous, whether it has its own magnetic field to deflect energetic particles. I would refrain from being overly enthusiastic. These days there is a planet discovered every day, so there will be more candidates. Hopefully in 10 years or so we will have a better idea what is going on.
This one has had three confirmed transits so far, so at least we’re pretty certain it’s real, unlike Gliese 581g. I wouldn’t be surprised if it turns out to be far less Earth-like than initial press releases would have us believe, but you’ve got to admit it, this is the closest we’ve got so far. It even orbits a sun-like star, has an orbital period not that distant from Earth’s, and probably isn’t tidally locked.
I’m not cheer-leading for a new Earth. I want to believe the truth, therefore I want to learn the truth. And I don’t see the correlation between your wishes about extra-terrestrial life and actual astronomy.
And, again, whether or not they do has zero relevance to what the actual truth is. You’re acting like what people believe or want to believe is going to change the great filter.
If a great filter is in our future, I desire to believe that a great filter is in our future (then maybe, just maybe, I can help us escape it). Wishing doesn’t change the universe we live in; wishing may help change the behavior of people. Thus, this wishing seems reasonably wise.
What is true is already so. Owning up to it doesn’t make it worse. Not being open about it doesn’t make it go away. And because it’s true, it is what is there to be interacted with. Anything untrue isn’t there to be lived. People can stand what is true, for they are already enduring it.
Note the “average” part. Average temperature on the Earth is +15°C (from Wikipedia, too). So, “just kidding”, not mostly.
Does anyone know what is the age of the corresponding star?
Distance to the star together with Kepler telescope being just 1.5 years old seem to mean that this is simply the first time we have the instruments for such a claim.
Scientists estimate that in the absence of atmosphere, the equilibrium temperature would be approximately −11°C.
Not bad!
If the greenhouse effect caused by the atmosphere is Earthlike, this corresponds to approximately 22°C (72°F) average surface temperature.
How much of this is just the Earthlike greenhouse effect function (worst case: the function is 22°C + [0 * planet_temp]) and how much is the planet?
If it has an Earth-like density then it would have mass 13.8 (2.43) Earth’s while its surface gravity would be 2.4 times Earth’s
Hopefully it is made of lighter materials or has a smaller core. I wonder if there are any studies on the long term effects of high gravity on the human body. I can’t imagine sleep would be comfortable or possible in 2.4G.
I guess this is very bad news, from a Fermi Paradox perspective. The more earth-like planets we see, the more likely it is that the “great filter” is on the other side of where we are now.
Why is this evidence that the “great filter” is ahead of us? How does seeing this distinguish between what you said and it being rare for life (especially intelligent life) to evolve, even in earth-like planets?
EDIT: I do see how it increases the chance of it being ahead of us. Since the observation “there are only rarely earth-like planets” would support the “great filter” being behind us, the observation “there are often earth-like planets” has to support it being in front of us.
Only if your beliefs prior to this discovery included any significant weight for an idea something like “A mathematically important factor in the Great Filter is likely to be a lack of roughly Earth-sized planets in the potential liquid water orbital zone of stars roughly the size of our sun.”
The Fermi paradox is that estimating various values makes it look likely that there’s other life in the galaxy. One possible reason that there isn’t is a lack of Earth-like planets. Another reason is the great filter. As such, finding Earth-like planets is evidence for the great filter. If it’s not caused by lack of Earth-like planets, then all the probability we assigned to that hypothesis has to go somewhere else, and some of it will end up at the great filter.
Right. And if you assigned very, very low probability to the hypothesis “there is a lack of Earth-like planets”, then there is nothing or next-to-nothing to reassign to other hypotheses, and thus no (discernible) increase in the probability of the Great Filter being ahead of us, and thus there is no “very bad news”. Thus, “Only if your beliefs prior to this discovery . . . ”
So, the question is, was it reasonable before this discovery to expect that there were very few Earth-like planets? Well, what does “Earth-like” mean? In this case, it means only that the planet is within a factor of 2.4 in radius of Earth and is in the “habitable zone” (that is, an orbit able to sustain liquid water) of a Sun-like star (implicitly defined in this case as within about ±25% of the Sun’s radiance). So given the incredibly broad definition of “Earth-like” being used in this case, our solar system already contains three Earth-like planets.
Now, it is possible that Earth’s solar system was a triple hyper-rare accident. But there was no reason, from either theories of planetary formation or actual observations, to expect so. So my prior probability assigned to the hypothesis “there is a lack of Venus-like planets in the galaxy” was difficult to discern from zero.
Planets may not be independent. Perhaps there’s something that made rocky planets more likely to form in our solar system, and thus we ended up with about three, and most solar systems ended up with none.
But do all three of those have temperatures of 72 degrees F?
Read the news carefully. Kepler-22b theoretically could have a temperature of 72 degrees F, sure . . . if it has an Earth-level greenhouse effect. But we don’t have any measurements of its temperature, and we don’t know the thickness or composition of its atmosphere.
Kepler-22b could have wound up with a Venus-type atmosphere, much thicker than Earth’s and high in carbon dioxide, and have a temperature far, far above 72 degrees F. It might have lost its atmosphere due to some early event and have radical temperature changes around the estimated −11 degrees C average. It might have an atmosphere that is thick and convective but transparent to infrared, with high albedo in the visible range, which results in it being an even-temperature ball even cooler than the no-atmosphere estimates make.
And that’s just atmospheric effects. Earth-type atmosphere combined with Venus-type or Moon-type rotation leaves you with an average of 72 degrees F, sure . . . but every spot alternately freezing and baking.
All “Earth-like” means in reference to Kepler-22b is that it’s within a factor of 2.4 in radius of Earth and is in the “habitable zone” (that is, an orbit able to sustain liquid water ore not depending on the local planetary characteristics) of a Sun-like star (implicitly defined in this case as within about ±25% of the Sun’s radiance). And by that definition, Venus and Mars both qualify as “Earth-like”.
The error bars are very large on this. Nothing is known about its atmosphere, density, albedo, whether it is solid or gaseous, whether it has its own magnetic field to deflect energetic particles. I would refrain from being overly enthusiastic. These days there is a planet discovered every day, so there will be more candidates. Hopefully in 10 years or so we will have a better idea what is going on.
If it has a nice thick atmosphere, the magnetic field doesn’t matter nearly as much.
Every now and then NASA has this kind of announcement. “New Earth found!”
Soon it becomes apparent, it isn’t quite like our planet.
This one has had three confirmed transits so far, so at least we’re pretty certain it’s real, unlike Gliese 581g. I wouldn’t be surprised if it turns out to be far less Earth-like than initial press releases would have us believe, but you’ve got to admit it, this is the closest we’ve got so far. It even orbits a sun-like star, has an orbital period not that distant from Earth’s, and probably isn’t tidally locked.
This has happened only 3 or 4 times. If this has annoyed you then I think your expectations are way too high.
It hasn’t annoyed me. I am glad, that there is no Earth. An Earth somewhere moves the Big Filter into our future, from our past.
Cheer-leading for a new Earth is not a very wise wishing.
I’m not cheer-leading for a new Earth. I want to believe the truth, therefore I want to learn the truth. And I don’t see the correlation between your wishes about extra-terrestrial life and actual astronomy.
You don’t. NASA and especially media do.
Why I hope the search for extraterrestrial life finds nothing
And, again, whether or not they do has zero relevance to what the actual truth is. You’re acting like what people believe or want to believe is going to change the great filter.
That’s not what hope is for.
If a great filter is in our future, I desire to believe that a great filter is in our future (then maybe, just maybe, I can help us escape it). Wishing doesn’t change the universe we live in; wishing may help change the behavior of people. Thus, this wishing seems reasonably wise.
You really walked into it, but:
What is true is already so.
Owning up to it doesn’t make it worse.
Not being open about it doesn’t make it go away.
And because it’s true, it is what is there to be interacted with.
Anything untrue isn’t there to be lived.
People can stand what is true,
for they are already enduring it.
Right?
Recent tests show I am likely not HIV+. I mean I’d like to know if I was HIV+, but generally this result makes me feel better.
Shouldn’t we feel better when we have good reason to lower our estimates of bad things happening to us? Or would that upset our inner Spock?
Yes, good news makes us feel good. But hoping you don’t have a terrible disease doesn’t make it less likely that you have a terrible disease.
If the Great Filter is in our future, then that’s where it is.
That sounds to me like hoping that there isn’t evidence that the Filter is in front, because we’d prefer the Filter was behind.
Yes, and? We would prefer the filter to either be behind or, failing that, be something good rather than bad.
Evidence which makes this seem more likely should make us feel relief. Evidence which makes this seem less likely should make us feel worried.
The cheer-leading comment is pointing out that many people have this backwards. It’s not saying that we’re able to impact where the filter lies.
Thanks, that’s much clearer. Regretfully, I didn’t get that point at all from the original comment.
To me it sounded like someone pointing out to someone else that his emotional response is probably based on some false cached thoughts.
Note the “average” part. Average temperature on the Earth is +15°C (from Wikipedia, too). So, “just kidding”, not mostly.
Does anyone know what is the age of the corresponding star?
Distance to the star together with Kepler telescope being just 1.5 years old seem to mean that this is simply the first time we have the instruments for such a claim.
.
Better go on a diet, eh?
Not bad!
How much of this is just the Earthlike greenhouse effect function (worst case: the function is 22°C + [0 * planet_temp]) and how much is the planet?
Hopefully it is made of lighter materials or has a smaller core. I wonder if there are any studies on the long term effects of high gravity on the human body. I can’t imagine sleep would be comfortable or possible in 2.4G.
You need a really soft bed.
I would expect that to just accelerate your suffocation!
There are probably morbidly obese people near you who can answer that question. (160lb becomes 400lb, which is not unheard of.)