One of the fun things about astronomy is that we can only know so much through empirical observation, yet we can "know" so much more through enlightened, mathematical guesswork. Such is the nature of the most interesting new science paper I've come across on the Internet today. In it, Wesley Traub of CalTech crunches some Kepler data and makes a tantalizing mathematical prediction: one-third of sun-like stars have at least one earth-like terrestrial planet orbiting in their habitable zones.
If that turns out to be the case, that's big news of course. The habitable zone, or the "goldilocks zone" as it's often known (not to close to the star, not too far away), is the orbital range where it's possible for liquid water to exist. Thus, it's the range where life as we know it could feasibly take root.
The planet-hunting Kepler observatory is designed specifically to seek out planets orbiting distant stars, and thus far its been a boon for exoplanetary science. In 136 days it has scanned some 150,000 target stars looking for the signature wobble exerted on those stars by orbiting satellites. In doing so, it has found 1,235 potential planets.
It's from that data that Traub has extracted his conclusion. He looked particularly at the stars that are most like our sun--those classified F, G, or K. He then looked at the kinds of planets that are most often found orbiting them and at what ranges they orbit. In his analysis, he notes many interesting (and somewhat expected) things, like the fact that nearly a third of the planets Kepler has found orbit their stars in less than 42 days, putting them too close to be in the habitable zone (this is also because planets closer to their stars are easier for Kepler to see).
Larger terrestrial planets out there in the habitable zone are harder for Kepler to spot, but that doesn't mean they're not there. And Traub says his number crunching allows us to get a pretty good idea of how many there should be. Using some math we don't pretend to understand, he plugged in the numbers for longer orbits--orbits in the habitable zone--into his analysis. The finding: "About one-third of FGK stars are predicted to have at least one terrestrial, habitable-zone planet."
That's not to say they are inhabited, or that they do have liquid water, or that they even exist. But Traub's math suggests that they should exist, at least until more data changes the equation. And for now, that spells a lot of potential goldilocks planets. Read the full paper via arXiv.
Interstellar colonization, anyone?
I'm going to apply these numbers to the drake equation...
-Spouting a fountain of nonsense since 1995-
I just want them to find the mythical Planet X. And its not the recently found 10th dwarf planet Eris. Once we find planet X, we will found our 2nd earth home, YEA!
I'm not surprised. three decades ago most astronomers would agree that our existence in the universe was fairly unique. With better scientific equipment and more accurate empirical data, we find that we are not unique, but we (like the multitude of atoms in the universe) are only one of many.
I think most stars have planets around them and a good deal of them (regardless of whether they are FGK category stars) with the potential of harboring life. Thus proving the lack of random order to the universe. We are simply the byproduct of a logical design. Therefore, there must be other worlds like ours. We are seeing living proof through the discovery of terrestrial and jovian worlds.
The most random and/or rare things tend to be extremely improbable to impossible to find.
Planet X was a concept developed following the discovery of Neptune in 1846. It was born from the possibility that there was in fact another planet outside of its orbit. The search for Planet X did not start until the turn of the 20th Century leading to Pluto's discover in 1930.
Since then Planet X has been the title for any unknown planet beyond the common knowledge of the initial nine. During the previous two decades three plutonian objects were discovered and named within this solar system; two outside of Pluto's orbit in the Kuiper Belt, and one in the Prime Belt between Mars and Jupiter. In succession, there names are Eris, Haumea, and Makemake.
There are possibly several dwarf planets/plutonian objects/planetoids that rest within the Prime and the Kuiper Belt. They are probably not subjected to be named unless used as they possibly range in the thousands. Every planetary discovery following has been extrasolar (i.e. planetary discovery in a foreign star system).
Planet X is a tagline for a sci-fi character that has no clue what planet they're on (i.e. Kurt Russell portraying Col. Jack O'Neil in the 1994 film Stargate).
I'd like to know how broadly "earth-like" is defined. Would Venus and Mars qualify as earth like? Would a planet like Gliese 581 d with a mass of 5.6 to 7.7 times that of Earth qualify as earth like?
Ok, ok, there you go being all factual and informative and everything.
Second, I want our science community to find the mythical planet X that is earth sister planet of which earth was seeded with human DNA. You know the science fiction planet X. I adore the Stargate series, don't you? It's real right, planet X?
I do appreciate the extra information you just provided. ;)
These planets are far too far away to colonize any time soon. It would be far easier to build on the moon, mars, the moons of mars, or to situate orbital colonies in LaGrange regions and in the asteroid belt(s). Of course, before we do that, there are still plenty of places on Earth too. But off-world colonies have the advantage of spreading humanity's eggs into other baskets, so we can not be so easily wiped out by a single mega-catastrophe. Orbital colonies also have great access to energy and transportation, so long as we can solve major problems, such as adequate radiation shielding, and life support system self-sufficiency.
As we clearly identify these goldilocks, perhaps we could point our satellite dishes at each of them for a while and try to hear some good chatter...
It's sad that we proceed with presumptions and limit our search to our definition of a habital zone. Even if we want to assume that liquid water is required for life, we cannot be sure of temperatures at these distant locals. Other elements and forces we have yet to experience may be on effect.
"Ok, ok, there you go being all factual and informative and everything. "
well its is called popular science, not popular science fiction.
but yes thank you phoenix for the info. That is why I thought eris was planet X. it was only "planet X" in the fact that for a brief period they thought it was the 10th planet, hence the X, but not THE mythical planet X. thank you for the explanation.
@Toran that is a good point. Time and time agian here on Earth the definition of life has surprised us and grown (just look at the taxonmy of "life" it has grown from a 3 kingdom system to a 5 or 6 kingdom system depending on if you study in the USA or the UK. plus it was only a couple decades ago they they realized archea evolved from a totally separate track than other prokaryotes). We have found life in the most improbably places thought for thousands of years to be 100% void of life.
but I suppose they figure these goldilocks zones have a higher probability of life. So far the only life we have found is on a Goldilocks planet. Earth.
Of course I like science fiction. It logically stands to motivate imaginative youth into academic interest in science.
It's just that by definition Pluto is Planet X, and Planet X is just a traditional verification of the unknown. The term is more common place for candid or satirical statements regarding unspecified worlds. For that matter their are several thousand Planet Xs.
It makes more sense to develop high speed space travel to other solar systems that have earth planets than trying to build on any of the planets in our system.
I love science and space travel as much as the next guy, and I sure do enjoy daydreaming about what we might be able to do one day.
However... I have to question whether or not this mission's life-cycle cost of US$600 million (including funding for 3.5 years of operation) really is really justified by what we're getting out of it. Great, we get to add a bunch of planets to our long list of known exoplanets. But what does that really do for us anytime in the next few hundred years?
We take that money away from people who work very hard, many of them to make sure they have the essentials of life from day to day. Then we dump it into a project that has no hope of ever doing anything remotely useful for these people. I would think there are some serious ethical issues with that, I know there are in my mind.
That $600 million could provide enough immunizations and basic supplies in 3rd world countries to save hundreds of thousands of children from early and painful deaths. Or it could be used in the US to build thousands of homes for homeless families. Or to provide educations to tens of thousands of kids who then have the potential of becoming scientists themselves, etc.
As fun and exciting as it is to "discover" these planets that we have absolutely no means of getting to for hundreds of years, I'd rather turn more kids into scientists now so that we can more quickly develop the technology to actually visit some of these exoplanets one day.
I wish they'd get a little more specific by what the term "Sun-Like". Do they generally mean all G-Type main-sequence yellow dwarf stars, or a more broader solar analogue? It's significant since something like 90% of the stars out there are cooler red or orange dwarf stars and stars like our Sun are probably more like 5-7% of the total population of stars out there.
planet x is very real.
The people of the world only divide into two kinds, One sort with brains who hold no religion, The other with religion and no brain.
- Abu-al-Ala al-Marri
I guess it is time we start constructing neutrino space ships/yawn.
The star types they mention in the article are F,G, and K. You gotta read the fine print. That's how they get ya.
We already know we can survive on a carbon copy of Earth. The real trick is trying to survive in "magnificent desolation."
Besides it's easier to get to these destinations now because they are closer. We still have to develop a relativistically quick means of journeying across stellar distances before we could ever consider mounting a mission outside of the solar system.
Your sentiment is noble, but we are not going to solve all of the world's problem over night. Besides, there are already organizations that exists to try and solve these problems and they get sufficient government funding which is provided in part by yours truly (the taxpayer). Just be thankful to whatever deity you may pray to that you are fortunate enough to be surrounded by luxuries such as a computer wired to the internet.
As for astronomical research, if you don't have the strategic vision to understand why we do this let me paint you a picture:
Humanity's knowledge in physics has evolved over time and it has achieved a level of mastery over the forces of the spacetime continuum. The once impossible has been proven possible and made into a reality, much as is with many instances in the history of the advancement of human civilization on Earth.
Humanity has achieved the ability to traverse interstellar distances within the blink of an eye. Following the first two successful missions to 581 Gliese d and g, a new mission is underway to HD85512 to verify the planet's potential for harboring life...
Moral of the short story: Making these discoveries now lays the foundation for exploration in the future. To cease such scientific research for lack of long term vision would prove ultimately detrimental to the future, setting us back several hundreds to thousands of years after we develop the means of instellar travel. By the time we develop these methods (especially after several hundreds of years) continued planet hunting will provide us with a library of known star systems that could range from the millions to the billions.
This would be better than the Louis and Clarke approach because space is otherwise featureless. Wondering aimlessly can trap you in a void indefinitely and send you on a trajectory clear of the galaxy without every reaching a star system. In order explore space, you gotta know where your going and the search for destinations starts here on solid ground.
In May of 2010 6.7 Billion U.S. dollars was being spent in Afghanistan a month.....1 month. This is 600 million dollars over a couple of years.....600 million is pocket change.
If the government wants to cut cost, cut the war in the middle east. (Yeah, yeah, it's not as simple as that...but whatever)
I wish to give you the award of long ranting and commentaries. First I like to say most WOA! YO DUDE, you write a lot of words and stuff! Followed how you write so much and not piss off inaka_rob. He is like such a jealous bandit for the lime light and all? Yo, friend, I am just playing. Be happy! ;)
But back to topic, I was looking at the picture in the article and I wondered why the sun is attacking the planet with these cosmic plasma balls of light and stuff. Does the sun have a beef with the planet?
I hope soon earth points our satellites towards these potentially life giving planets to hear some kind of chatter of communication. Now wouldn't that be cool to hear a new version of Star Wars from a different planet and all!
Seriously, I appreciate the extra information you provide, thanks!
"About one-third of FGK stars are predicted to have at least one terrestrial, habitable-zone planet."
A total of 22.7 percent of all the stars in our galaxy are class FGK stars, F = 3%, G=7.6%, K=12.1%, it was suggested that 33 percent may be within the habitable-zone.
There are approximately 300 billion, 300,000,000,000, stars in our Milky Way galaxy, 150 billion in the average size Galaxy. There's approximately 200 billion galaxy's in our know universe. That would mean that there are about 22.70 billion, 22,700,000,000 planets, in our Milky Way's habitable-zone or approximately 2.27X10²¹, 2,270,000,000,000,000,000,000 planets in our universe within a class FGK stars rated habitable zone.
Of course, a "habitable zone" is a nebulous term, as things like atmospheric gas can greatly affect the surface temperature of a planet. As well, internal temperature can create a "crust" effect (as is hypothesized about Europa).
Still, 22.7 billion planets in the Milky is not going to give you a good shot at a planet where you can take off your helmet and breathe (we are very fragile in what we breathe).
As for the 600m being spent on vaccines - to what end? Save them from Malaria to insure their starvation of resource competition, or 100m for vaccines on some with 500m for food support? Of course, what about the antibiotic when their population density gives them cholera?
You cannot and will not alieviate human suffering.
I'm a wealth of knowledge seeking to educate those without. I wouldn't call much of what I do ranting (though a lot of it is). I just legitimize my general platforms with details and evidence. That often takes a lot of words, but might be shorter when spoken.
i saw on "The Universe" that there are more than 3 suns, this is interesting, good thing I'm going to college to be an astrophysicist
I really do hope some science community finds intelligent life we earthlings can communicate in my life time!!!
If my wording sounded less complimentary, I like to rephrase myself and just say, I enjoy the additional input you provide and say thanks. ;)
Marcoreid writes: We take that money away from people who work very hard, many of them to make sure they have the essentials of life from day to day.
Not really. Although the poor pay payroll taxes which CAN amount to as high a percent as hedge fund managers pay on their entire salary... The point I want to make is that science is boring, without cool projects like Kepler to stimulate the minds of budding scientists, who would want to get involved in it? What would be the point? We need research like Kepler to whet the appetites and fire the imaginations of children into pursuing careers in science. Without that, who would want to do it?