Looking For Jupiter-Class Planets Indicates Solar Systems Like Ours Are Rare (theconversation.com) 90
An anonymous reader writes: A high school senior from New York analyzed data for more than 1,100 stars and pinpointed the frequency of Jupiter analogs (planets with similar mass and orbital period to Jupiter) to 3%. He published his results in a paper for the Astrophysical Journal. The relative rarity of Jupiter-like planets indicates that true solar system analogs should themselves be rare. By extension, given the important role that Jupiter played at all stages of the formation of the solar system, Earth-like habitable planets with similar formation history to our solar system will be rare.
Young Man Given Undue Credit; news at 11 (Score:2, Insightful)
From the article:
Look, it's great that this kid is involved, but quit lying about his contribution; when surrounded by such co-authors, even a monkey could have participated successfully.
Re:Young Man Given Undue Credit; news at 11 (Score:4, Insightful)
or maybe he actually did the grunt work of digging through the data and running the numbers?
who knows, but lots of undergrads and even grad students get their first publication by basically doing really pedestrian grunt work for fully independent scientists. Even famous scientists usually start out that way. Why should it be any different for this kid?
Very rare indeed (Score:1, Informative)
"Solar systems" like ours are rare indeed, because there is only one Solar System.
It's a proper noun.
The term the article was looking for was planetary system.
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The term star system is also misused a lot in the case when people mean planetary system. Generally star system refers to a system of stars, e.g. a binary star system.
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The astronomy community makes an exception to that pattern when you refer to a specific named star's system of planets by the star's proper noun name.
e.g. Sol is Solar System as Tau Ceti is to Tau Ceti system.
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I'm also wondering if there are solar systems (or whatever the proper name is) that aren't rare.
Is there some standard kind of solar system that is very common?
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LOL .. scary, dangerous, and hostile to life. :-P
But, really, think about it ... even at 3% that's a crap pile of solar systems in our galaxy alone.
I mean, even 3% of "beyond really grasping", is still "beyond really grasping".
To quote Armageddon ...Begging your pardon, sir, but it's a big ass sky.
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It seems so. The common kind have large planets (or companion brown dwarves possibly) very close in to the star, often in quite elliptical orbits.
Call 'em solar systems. Analogy: The Moon (Score:3, Insightful)
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That's a popular colloquial usage, but the astronomy community doesn't (yet?) accept "solar system" as a generic term like it does with "moon."
For the time being, the correct term is planetary system. Usage of "solar system" as a generic term is wrong.
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That is not correct.
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That is straight out of the IAU definition where a planet must by definition orbit "The Sun", which is the proper noun and name of a very specific star that I happen to see every day.... during the daytime as its apparent magnitude is quite high.
Yes, it is correct that planets can only orbit The Sun. Period.
And I would agree that heliocentric definition really needs some significant work. Stuff that orbits other starts are not planets, but rather exoplanets with a very murky definition as to what is or is
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The IAU's definition is only limited to the Solar System because we don't have enough observational data to define extrasolar planets so specifically. If we had as clear a view of other planetary systems as we did our own, then we wouldn't need the distinction between planet and exoplanet.
A separate draft definition for extrasolar planets was established by the IAU in 2001 and includes the criterion: "The minimum mass/size required for an extrasolar object to be considered a planet should be the same as tha
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The moon is called Luna when we want to be really clear which moon we're talking about. It's just that in most contexts nobody would mean any moon other than the nearby visible one.
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The Moon is called Luna by a bunch of science fiction authors and a bunch of folks who for some reason choose not to communicate in English when they are otherwise communicating in English. The proper term when using the English language is simply "The Moon".
Selene and that big hunk of cheese in the sky are somewhat acceptable alternatives, but you can take that for a grain of salt. A great many cultures each have their own term which is used for that fairly large (from an apparent viewpoint of somebody o
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I've heard that theory before, and I doubt its accuracy.
Life like ours, out on the surface, would have difficulty living without the magnetic field, but we evolved on this planet. Life that evolves in an ocean doesn't have to worry about radiation. Look at Europa, for instance - we think it's possible for life to evolve there, and it's in a much harsher environment than the Earth would be even without a magnetic field.
If life evolved in an ocean on a planet with a dead core, and eventually left the ocean
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That said, while life might be more common than you think, you might be right about intelligence - at least at our moment in time. I would be very surprised, however, if we were the first intelligent life in this galaxy.
While I would agree with you so far as intelligent life in the universe as a whole, since that is so huge, I wouldn't bet so strongly about some other sentient species being found in the Milky Way. The problem can certainly be described by the Drake equation, but I also argue that there are additional variables which apply.
On top of that, of all of the species of "intelligent species" you might encounter, how many will be tool using spacefaring species as well? On the Earth there are several other primate
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I was just considering intelligence, not necessarily space-faring. Honestly, we're barely a space-faring race ourselves.
Either way, we're working on way too little data at this point to do more than guess. We know a bit more about other planetary systems than we used to, but we're still largely ignorant. We've got statistics we can work with, but the variables we're feeding into it are flimsy at best. My reasoning for thinking we're not the first intelligent species is the number of stars in the galaxy
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Indeed. The fact that simple life appears to have been present on Earth for as far back as we have a geologic record (the first half-billion years of record has been lost to subduction) would seem to suggest that simple life may actually form relatively easily (maybe something about the hot, violent early environment of Earth was really unusual, but that doesn't seem to be the way to bet). On the other hand, the fact that life teemed across our planet for at least 3.5 billion years before we see much evid
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Never heard of him. Perhaps the odds are even lower than we thought?
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Isn't poorly-informed pedantry fun?
Obviously you need some sort of substrate for life to evolve on, but "Habitable Zone" has a well established definition of "the distance from a star where liquid water can exist on a planet's surface." It's a fairly fuzzy definition since there's lots of planetary effects that can come into play (and it doesn't even consider the habitability of gas-giant moons, nor of non-aqueous life), but it is a well established definition, and one doesn't rely on there actually being
We can only detect planets they pass their star (Score:5, Interesting)
It's rather premature to declare all those systems devoid of planets when our primary means for detecting possible planets is when they pass between our planet and their star at the same time we observe them. Jupiter takes 12 years to make an orbit. As a simple logic problem, that means that we have to one opportunity to observe Jupiter passing between Sol and some sort of earth-analog in another system.... and that makes the HUGE assumption that that earth-analog is aligned with the solar system's orbital plane. If the earth analog happens to be staring down north-south on Sol, it isn't going to detect any planets.
There are a few other ways to detect planets, but those are special cases, again, very rare, and detecting very unique planets.
Detecting Sol-like systems is still extremely difficult.
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We are living in a 3D world, not in a 2D world. ... our plane ... or from top to bottom. However you are right, the ways how a extra solar system my be 'turned' toward us so we can see it with current techniques is quite restricted.
An observed planet does not need to be in the plane of our solar system. It does not matter if the observed planet cuts over its sun from left to right
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We are living in a 3D world, not in a 2D world. ... our plane ... or from top to bottom. .
An observed planet does not need to be in the plane of our solar system. It does not matter if the observed planet cuts over its sun from left to right
I think he meant if we are looking at the "north pole" of the other star, then any planets moving around it will not pass between it and us.
Re:We can only detect planets they pass their star (Score:4, Interesting)
We can only detect planets they pass their star
Wrong [wikipedia.org].
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Well, you've exchanged edge-on for perpendicular as a limitation.
Congrats.... you've exactly doubled the potential cases for detection, which is still a small percentage of the systems we can observe.
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Your parent was wrong and you missunderstood the animation on the wiki.
Perpendicular dors not make a doppler effect.
Only a sun that drifts away from us and then comes back toward us produces a doppler effect.
Hence the planet still needs more or less cross the sun from our point of view. (the planet my near miss though, in this case)
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Actually: not wrong.
To use the doppler method to find a distant planet, the planet still needs to cross its sun or needs to be in a very close range of degrees above or below (besides on side or the other) of that sun. So the limitation to find it is more or less the same as crossing the sun.
Hint: the animation on the wiki page is missleading. There is no doppler effect if you look on a planets orbit from 'atop'.
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So the limitation to find it is more or less the same as crossing the sun.
It's still wrong to say "We can only detect planets they pass their star" which is all I was disputing. I understood the animation and the technique.
Re:We can only detect planets they pass their star (Score:4, Interesting)
Furthermore:
https://en.wikipedia.org/wiki/... [wikipedia.org]
So they are expecting to be able to detect planets via "perpendicular" observation (and may have already done so, but it's not been fully confirmed).
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Wow, that is a nice link.
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There is also direct imaging of planets, something that doesn't necessarily need to be edge on. While difficult to pick out planets in that fashion, it has happened for several planets already [wikipedia.org]. That at least provides a sort of gut check to verify the statistical soundness of planets found using other methods.
Re:We can only detect planets they pass their star (Score:4, Informative)
It's rather premature to declare all those systems devoid of planets when our primary means for detecting possible planets is when they pass between our planet and their star at the same time we observe them. Jupiter takes 12 years to make an orbit. As a simple logic problem, that means that we have to one opportunity to observe Jupiter passing between Sol and some sort of earth-analog in another system.... and that makes the HUGE assumption that that earth-analog is aligned with the solar system's orbital plane. If the earth analog happens to be staring down north-south on Sol, it isn't going to detect any planets.
There are a few other ways to detect planets, but those are special cases, again, very rare, and detecting very unique planets.
Detecting Sol-like systems is still extremely difficult.
Well unless the scientist working on this are total moron, you can quite easily do some statistic analysis to guess the number of Jupiter-like planet in other planetary system even with those complication . Here's a quick example. Let's suppose the world is in 2D and make every orbit are perfectly round to simplify things. A planet have a 360 orbit and let's say we can only see the planet for 0.01 (so 1/36000) of their orbit with 100% accuracy. So if you scan 72000 star and find 4 planets, you can then make the assumption that there's 2 gas planet per planetary system on average.
Am I missing something?
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I hope so.
If you simplified to a 2d world then we should be able to see every single planet.
As I said, I've made my example 2D so simplify my explanation but 3D isn't much harder (see below)
So if you scan 72000 stars and found 4 planets, you can make the assumption that there are 4 planets out of 72000 stars.
Wrong, plain wrong.
You have a test that got 1% chance to detect a disease and you want to test how many people have it. You make the test on a million person and you got 10 positive result. The conclusion is that, statically, 10 000 got the disease out of the million, not 10.
Your statement is true only if you are 100% confident that you'll detect 100% of the planet by scanning a star for X time. Which isn't the
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Right now, the number of systems we've detected is somewhat above a thousand. There are around 100 billions stars in our galaxy alone. So, in other words, the people who wrote that article have decided that a 0.000001% sample is enough to draw conclusions.
On top of that, what a surprise, said conclusion is that the Solar System is a (very?) rare occurrence. I haven't taken the time
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Am I missing something?
So, 9 women can produce 1 baby in 1 month?
There is a reason for the quote: Lies, damned lies, and statistics.
Wrong, Brooks' law doesn't apply here and you're completely missing the point.
Brooks' law is about work parallelization. It mean that if it take 100 hours for a worker to do a project, 2 workers won't necessarily make it in 50 hours and that 100 worker will certainly not make it in 1 hour.
Here's a good example on how statistic work in this case :
You have a test that got 1% chance to detect a disease and you want to test how many people have it. You make the test on a million person and you got 10 positive result. The conclusion is that, statically, 10 000 got the disease out of the million, not 10.
Your statement is true only if you are 100% confident that you'll detect 100% of the planet by scanning a star for X time. Which isn't the case here.
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Maths are a tool to be used in astronomy. When you get to the poin
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What's the distribution of the stars' ecliptics relative to the galactic equivalent? I know ours is tilted, or the milky way would be round the equator, which it isn't. And I looked it up.
Presumably we can deduce it for those where we can detect expolanets by, say, doppler shifts. But isn't there a selection bias there?
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I know ours is tilted, or the milky way would be round the equator, which it isn't. And I looked it up.
I read that as "and I looked up" which would also work.
Too soon (Score:5, Interesting)
Jupiter has an orbital period of 12 years. From what I've understood it takes 3 passes to confirm an exoplanet, meaning 0-12 years to initial discovery + 2*12 = 24 years for a Jupiter-class planet. It's only been 23 years since the first exoplanet was discovered in 1992 and detection capability has improved much since then, so it's way too early to tell. Maybe you can start making semi-educated guesses from lack of candidates, but that too seems premature. In another 15-20 years, we'll have much better answers.
Re:Too soon (Score:4, Informative)
That's if you are using the difference in light to detect the planets but there are other ways. If you use the wobble of the star caused by the pull of the gravity by the planet you don't have to wait for three rotations of the planet. It also allows you to examine star systems that have an orbital plane shared with Earth. If we look "down" on the system we would never see a planet move in front of the star but we would see the star move.
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Wobble. Right. Are you even remotely serious?
Yes, he is being serious. This is actually done in a variety of ways. Read up on it before being so critical... and Doppler shifting of stars on a periodic frequency is one of the methods used to detect exoplanets (among a great many other techniques).
Perhaps the GP wasn't using the proper terminology, but then it is you that needs to get a life here as posting on Slashdot isn't a doctoral defense forum.
Junk science? (Score:1)
In what way can an analysis of 1,122 stars be considered significant?
How were these 1,122 selected? The paper is almost deliberately vague on this point, simply choosing to refer to them as "our sample".
The phrase, "A high school senior from New York analyzed data" is highly misleading. There were 13 authors.
The paper only takes data from one telescope. Presumably this paper was not the telescope's primary focus (if it was someone needs to pull the funding now) so the data has been collected as a side pr
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How were these 1,122 selected? The paper is almost deliberately vague on this point, simply choosing to refer to them as "our sample".
It isn't that big of a deal if you are considering the database of stars that have been found with the Kepler Space Telescope [nasa.gov], which is by far the largest source of information about exoplanets available at the moment. You say it was data taken from just one telescope, but the science is about as sound as it gets.
Most of your questions can be answered by simply removing your ignorance about this particular instrument, which is 100% dedicated to just analysis of exoplanets and gathering data about them. Wh
For sufficiently small values of 'rare' (Score:4, Interesting)
At roughly 3%, that means about 100x as many Jupiter analogs in our galaxy as there is carbon dioxide in our atmosphere (by percentage).
At roughly 3%, that means there are only about 10 billion Jupiter analogs in our own galaxy of roughly 300 billion stars.
Yes, 'rare' is a relative word especially when you are dealing with numbers that seem to be beyond human comprehension.
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At roughly 3%, that means there are only about 10 billion Jupiter analogs in our own galaxy of roughly 300 billion stars.
Yes, 'rare' is a relative word especially when you are dealing with numbers that seem to be beyond human comprehension.
Exactly...er....um...... relatively speaking.
This is why we need to develop Star Fleet and mine di-lithium crystals and platinum group metals from asteroids.
Its seems like a better idea then burning jet fuel and bombs for political reasons that won't matter in the absense of matter.
If you look for a 1% setup ... (Score:1)
then you'll likely get a 1% result. Divide the pie up and you get lot of pieces, funnily. There's probably a name for it too.
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True, but statement is too narrow. (Score:2)
The lack of jupiter orbit type gas giants in the sample does not mean a dirth of possibly habitable candidate objects.
Like always, they completely ignore the prospect of large numbers of moons around extra solar gas giants, and thus ignore the prospects of possibly habitable moons.
Granted, there isnt sufficient data to make even rough estimates of that yet, since we cant really "direct image" extra solar planets to look for moons, but that is likely to change when James Webb launches and starts performing s
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Almost as disturbing as their failure to acknowledge that there may be dozens of species of jumping spider that are currently unknown! Indeed, these are just two of the many things that might be true that they fail to acknowledge in their paper on a particular study that wasn't studying those things....
Detection bias (Score:2)
Based on the plot, it looks like the type of planet/orbit detected is closely tied to the detection method. That implies we are not getting a full sample of actual planets.
High Schoolers (Score:2)
This is why you don't leave important scientific "facts" to high schoolers to "discover"
Cool, the kid analyzed some existing data, but what about the truth to said data? How do we know the transit period of a planet around a star? We measure the dimming light of the star on a periodic basis. After three transits, we can determine with an amount of certainty that it is indeed a planet, and not just other objects obscuring the star.
Jupiter transits Sun aprox every 12 years. This would mean at a bare minimum o
sampling bias (Score:2)
The reason we find so many gas giants close to stars is because those are easy to find. Jupiter-like planets are much harder to find, and hence underrepresented in the data. You can use the data as a lower bound, but not as an upper bound.
It's a Highlander solar system! (Score:2)
Gliese 581 (Score:2)
I was under the impression that one planet 8x the size of earth orbits close to a dim star was in a zone where water would be a liquid and hope for life, yet Wikipedia claims otherwise.
https://en.wikipedia.org/wiki/... [wikipedia.org] (it being likely to have a runaway greenhouse effect).