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Our Solar System: Rare Species In Cosmic Zoo

samzenpus posted about a year ago | from the best-in-class dept.

Space 197

astroengine writes "Pulling from 20 years of research since the first discoveries of planets beyond our solar system, scientists have concluded that Earth and its sibling worlds comprise what appears to be a relatively rare breed in a diverse cosmic zoo that includes a huge variety of planet sizes, orbits and parent stars. The most common systems contain one or more planets one to three times bigger than Earth, all orbiting much closer to their parent stars than Earth circles the sun, says astronomer Andrew Howard, with the University of Hawaii."

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God made it. (-1, Flamebait)

superslacker87 (998043) | about a year ago | (#43617411)

See? We are the only place in the universe that can sustain life.

Re:God made it. (2, Insightful)

bejiitas_wrath (825021) | about a year ago | (#43617435)

The Universe is so large that it cannot possibly be that we are the only life thriving on a planet orbiting a star. There would be countless other lifeforms out in space on countless planets. I wonder if it is possible that a rogue planet could harbour life. Say if it was thrown out of a solar system but volcanism was keeping it warm enough for life to survive. How long would that last? As that was a plot point in Star Trek Enterprise.

Re:God made it. (1)

khasim (1285) | about a year ago | (#43617463)

As that was a plot point in Star Trek Enterprise.

I think that the main issue is that people see the TV shows and movies and think that "life" has to look like that.

But those are just theatrics so that human actors can play the parts. Look at the variations of life on Earth. From whales to worms.

The Universe is so large that it cannot possibly be that we are the only life thriving on a planet orbiting a star.

It's not just whether there are other civilizations out there. It's also whether either of us would develop technology that the other would be able to understand or recognize as signals AND broadcast them during the time when they could be received AND with sufficient power to be received.

Re:God made it. (5, Funny)

Black Parrot (19622) | about a year ago | (#43617469)

As that was a plot point in Star Trek Enterprise.

I think that the main issue is that people see the TV shows and movies and think that "life" has to look like that.

But those are just theatrics so that human actors can play the parts. Look at the variations of life on Earth. From whales to worms.

Are you telling me that the galaxy isn't full of people who grow lumps of rubber on their heads?

Re:God made it. (1)

khasim (1285) | about a year ago | (#43617549)

Are you telling me that the galaxy isn't full of people who grow lumps of rubber on their heads?

Who happen to breath the same combination of gases and who are comfortable in the same temperature range and gravity range.

Not to mention the inter-breeding. So much inter-breeding.

But that's what happens when you have writers who know more about getting a job writing for a show than they know about science.

Re:God made it. (4, Interesting)

Samantha Wright (1324923) | about a year ago | (#43617635)

Two fun facts:

1. In TOS, it was somewhat legitimate science fiction [memory-alpha.org] to suppose that alien worlds could be identical to Earth. It was theorized that we might be the "optimal" path for evolution to take, and hence things might develop along extremely similar lines. This is why there is literally an episode [memory-alpha.org] where they find a planet that has gone through World War III, which ends with Shatner moralizing about the virtues of the US Constitution. This was much-loved because it meant they could re-use props from other productions. Other exciting examples of this kind of imaginary thriftiness include the modern Roman empire [memory-alpha.org] , although many were softened: the 20s gangster planet [memory-alpha.org] was created by accidentally leaving a history book behind, and the Nazi episode (TM) [memory-alpha.org] was deliberate meddling by "a Federation historian" (whom I guess we'd call a neo-Nazi today.)

2. By TNG, the technobabble problem was so bad that the actors sometimes rehearsed with scripts where the technobabble hadn't even been filled in yet [memory-alpha.org] . The writers wanted to write a human drama, and science was just a prop thrown in, to support that. To their credit, it at least created a popular show, something which other science fiction programmes had a lot more trouble doing.

Re:God made it. (1)

able1234au (995975) | about a year ago | (#43617869)

Perhaps it was just that they had all these unused costumes and sets around so it was cheap to do.... just saying...

Re:God made it. (4, Informative)

Cinder6 (894572) | about a year ago | (#43617687)

To be fair, TNG did explain why (most) aliens were humanoid in the episode The Chase.

Re:God made it. (1)

cmotdibbl3r (1353581) | about a year ago | (#43619233)

In TOS, Kirk asked Sargon why he kept calling them "his children". Sargon told Kirk that they seeded the galaxy with their likeness eons ago. Kirk responded that there was evidence for independent development of humans on Earth but Spock said this seeding would explain Vulcan mythology. One of the appealing features of the TOS as originally pitched to DesiLu was that they would visit "Class M" planets, so humanoid.

Re:God made it. (4, Funny)

Black Parrot (19622) | about a year ago | (#43617725)

Not to mention the inter-breeding. So much inter-breeding.

Who'd want to be the captain of a starship, if not for all the opportunites for inter-breeding?

Re:God made it. (1)

SJHillman (1966756) | about a year ago | (#43618501)

By the 1701-D's time, that job was relegated to the First Officer's beard.

Re:God made it. (2)

tmosley (996283) | about a year ago | (#43619485)

You could do that from the comfort of you own home. At least in a few states.

Re:God made it. (0)

Anonymous Coward | about a year ago | (#43617843)

and most importantly, who speak standard US English.

Re:God made it. (1)

Joce640k (829181) | about a year ago | (#43618277)

...who speak standard US English better than many Earth-natives.

Re:God made it. (0)

Anonymous Coward | about a year ago | (#43618303)

Turn in your geek card.

Universal Translator

Re:God made it. (0)

Anonymous Coward | about a year ago | (#43618327)

The USA don't exist in Star Trek. No US English.
And you forget the universal translator.

And you forget that several species have been presented to have a language not translatable by the UT.
The Sheliak for example.

In Enterprise, before the UT was invented they had to employ a human translator extremely talented in translation unknown languages.

So. No. They don't all speak English.

Re:God made it. (1)

SJHillman (1966756) | about a year ago | (#43618505)

And even if the UT did work, it didn't always make sense. Darmok was one of the best episodes imo.

Re:God made it. (1)

Anonymous Coward | about a year ago | (#43618645)

Sokath, his eyes uncovered.

Re:God made it. (1)

tehcyder (746570) | about a year ago | (#43619143)

As that was a plot point in Star Trek Enterprise.

I think that the main issue is that people see the TV shows and movies and think that "life" has to look like that.

But those are just theatrics so that human actors can play the parts. Look at the variations of life on Earth. From whales to worms.

Are you telling me that the galaxy isn't full of people who grow lumps of rubber on their heads?

And speak English with an American accent?

It's full of... (1)

neoshroom (324937) | about a year ago | (#43619191)

The galaxy is full of people who live on moons of gas giants because they had a lot of incentive to develop space technology to hop from moon to moon.

The galaxy is full of people who grew up in low-gravity environments, because they are more comfortable living in space and thus travel is easier for them both energetically to get there and biologically to live there.

The galaxy is also full of people who grow lumps of rubber on their heads, but that's just because it is the latest rage in all the Alpha Centauri fashion holos.

Re:God made it. (1)

Internetuser1248 (1787630) | about a year ago | (#43617791)

It's not just whether there are other civilizations out there. It's also whether either of us would develop technology that the other would be able to understand or recognize as signals AND broadcast them during the time when they could be received AND with sufficient power to be received.

Actually I don't see it as being about that at all. The debate here is about other species existing, us knowing about them specifically is merely a question of our own knowledge about reality and has no bearing on reality outside of our heads. It is very anthropocentric to base theoretical assumptions about extraterrestrial life on our own ability to perceive that life.

Re:God made it. (1)

Joce640k (829181) | about a year ago | (#43618095)

As that was a plot point in Star Trek Enterprise.

I think that the main issue is that people see the TV shows and movies and think that "life" has to look like that.

But those are just theatrics so that human actors can play the parts.

Yep. All intelligent life just happens to be bipeds with the brain in a head at the top with a face that has eyes above the nose and the mouth just underneath it.

I'm still wondering how Spock can be the offspring of a human and a Vulcan - complete with two hearts and green blood!

Re:God made it. (5, Insightful)

hairyfeet (841228) | about a year ago | (#43618819)

Which was why Roddenberry did it that way, I saw an interview with him once where he was asked why all his aliens were forehead aliens instead of anything exotic and he pointed out 1.-The exotic aliens on Dr Who looked like crap, and 2.-90% of an actor's craft is done with his face and when you can no longer see the actor's face he can no longer convey emotion. Joss Whedon said the same thing when asked why he got rid of the cool "American Werewolf" in the first season for a classic wolfman, he said all the animated wolf could do was snarl, it couldn't be scared or show pain or any emotions whereas Seth Green could make you feel for the monster by putting bits of the man into the performance.

As for TFA, to quote Ian Malcolm "Life finds a way". Just look at how there is life on this planet in some of the most hellish places, like thermal vents on the bottom of the ocean. I remember reading an article talking to the guys that went down so deep in the Marianas trench and one of the things they were talking about was how you had flat fish even down that deep. To say that our planet is so far unique for supporting our monkey asses is fine and dandy but anybody who thinks that means there couldn't be life on those because we wouldn't survive is just being arrogant. This is why i support exploring the oceans of Europa with a probe, from what we saw the oceans under the ice are warm and flowing, if there is any place in our own solar system that would have life my money would be on Europa.

The problem isn't that there may or may not be life out there, the problem is even in our own galaxy the space is just so damned vast that just saying hello could take 10 million years. Until we can find a way around that pesky little relativity thing we are just pulling ideas out of our asses because with our best telescopes its the equivalent of stepping out a single inch, our reach is just too small when compared to just what is in our own galaxy, much less the thousands of other galaxies, that for all we know earth like planets are a dime a dozen, there just aren't any in the few feeble inches we can reach out with our current tech.

Re:God made it. (1)

thomasw_lrd (1203850) | about a year ago | (#43619079)

Damn, I wish I had mod points. That may be the best explanation I ever heard.

Re:God made it. (0)

Anonymous Coward | about a year ago | (#43619091)

The main issue that people see with shows like that is not that humans play the aliens. The issue people see is that those aliens don't believe in God. Alien life does have to look like that. God made everything, including us...........Therefore all aliens will look like us. Sound logic. /sarcasm

Re:God made it. (0)

Anonymous Coward | about a year ago | (#43617491)

Likely not long. Mercury seems to have the fastest orbitting speed at almost 50km/s.

If it were shot at proxima centauri at 4 light years away, it would take about 23 000 years to reach it. I didn't take into account how fast proxima centauri would be moving, if mercury was shot at it while it was moving trowards mercury, it would be a lot faster, if the other way around, it may even never reach it.

23000 years without solar energy would likely be a very, very long time for any "advanced" life. There would be no possibility for photosynthesis, for example.

Also, a planet that has enough vulcanism for 23 000 years probably isn't all that inhabital for most larger species. Bacterial colonies and single cell life may still thrive as it did during earths vulcanic period.

Now, I know I am leaving out some very major factors here, but it just seems to me that its utterly unlikely you will find complex lifeforms on such planet. 23000 years of darkness would also be a very very lucky shot. It has a way bigger chance to keep going in the space between stars without ever reaching close to one.

Re:God made it. (3, Informative)

Intrepid imaginaut (1970940) | about a year ago | (#43618283)

The Universe is so large that it cannot possibly be that we are the only life thriving on a planet orbiting a star.

Unfortunately it quite possibly can. Since we have only one instance of life on record, in the absence of further evidence all we have is conjecture. We might very well be alone in here.

The right conditions? (3, Informative)

dimeglio (456244) | about a year ago | (#43618449)

The book Rare Earth dwells into the possibility we're in fact quite exceptional. I've seen plenty of debate regarding some of the statements and conclusions drawn by the authors but nonetheless, "intelligent" life seems a lot less common than expected. That being said, we're improving our "life detection" skills and it might be possible, in a few years, to actually "scan" a planet from earth and detect elements, through spectrum analysis [labspaces.net] , which point to evidence of life.

Re:The right conditions? (3, Insightful)

smpoole7 (1467717) | about a year ago | (#43619029)

> Rare Earth

I assume you're speaking of the book by Peter Ward and Donald Brownlee? I'll have to look at that one. As I've posted here previously in other threads, I recently finished Alone In The Universe by John Gribbin, which reaches the same conclusion. I don't know about Rare Earth, but Gribbin's book is based on tons of new computer simulations.

Gribbin points out that *simple* single-celled life may indeed be common within the Galactical Habitable Zone. That's an extremely important distinction. Making intelligent life is the trick. A number of very unlikely things have to work out for that.

This flies in the face of intuition. (And besides, Geeks have gotten so used to seeing Klingons and Drazi and Wookies in movies and on TV, it's just taken for granted now.) We just *assume* that the natural end course of evolution is some form of intelligence: give evolution a good, robust single cell to work with and a few billion years of time, and you will inevitably end up with some form of intelligence. But that's not necessarily so.

As someone else points out here, those who actually study this stuff are reaching a consensus that intelligent life (again, don't miss that!) may indeed be extremely rare in our universe. Yes, even though the universe is huge and large and unfathomable.

Re:God made it. (4, Insightful)

StripedCow (776465) | about a year ago | (#43618467)

The Universe is so large that it cannot possibly be that we are the only life thriving on a planet orbiting a star.

There is a huge fallacy here.

The reason that we are on this planet is of course the fact that life IS possible here. However, the chances of life occurring somewhere might be 1 in a gazillion.

It might even be that life exists only in a small part of the multiverse (http://en.wikipedia.org/wiki/Multiverse) Let us assume that at the sub-atomic scale, decisions are not taken at random, but that at every (let's say binary) decision the universe splits in two halves (one half taking one outcome of the decision and the other half the other). Then if --in this big tree of universes-- life exists somewhere, then it may appear in one universe as if either there was a God that created this life, or, to the more scientifically oriented life-forms, it may seem that life may occur elsewhere in the same universe. But the reality is that the formation of life may be much less likely than we think, and other life may exist only in parallel universes.

Yes, we have created small DNA-like structures in reaction chambers. However, life on Earth will not function with only some random string of DNA. Complicated machinery (ribosomes etc) is needed to actually make life work. And we know absolutely nothing about the probability of this machinery to come into existence from scratch.

Re:God made it. (1)

rich_hudds (1360617) | about a year ago | (#43618557)

The Universe is so large that it cannot possibly be that we are the only life thriving on a planet orbiting a star

Amazing logic there. Most people who have given it serious consideration think it is perfectly possible that Earth has the only life in the universe.

Re:God made it. (0)

Anonymous Coward | about a year ago | (#43618833)

Yep. Some posit the probability of intelligible life as essentially zero -- meaning that Earth is a fluke. Still, such guesses are just that -- guesses -- and though educated, that term is relative, as there is at present no way to know all the factors. Even Drake admits he was only spitballing.

Re:God made it. (1)

tehcyder (746570) | about a year ago | (#43619273)

Yep. Some posit the probability of intelligible life as essentially zero -- meaning that Earth is a fluke. Still, such guesses are just that -- guesses -- and though educated, that term is relative, as there is at present no way to know all the factors. Even Drake admits he was only spitballing.

The probability of intelligible (sic) life is NOT "essentially zero". However infinitesimally small the probability, it's not zero, since we know there's life on at least one planet.

However, as someone says above, the problem is that because the probability is so very, very low that any other intelligent life is simply too far away for us to ever contact. If we have to look to another galaxy to find our neighbours, well...short of a stargate-type piece of magic we may never meet them. We might trade millions of years old light speed signals, but that's not really going to help and we're not going to have much of a dialogue.

Re:God made it. (0)

Anonymous Coward | about a year ago | (#43619045)

Were...not are. We are a warlike species...I would be suprised to find another species, lifeform, even bacteria yet alive in/on another world. Just because of the energy required too reproduce. Implies a second species, to feed upon, implying predation,implying feast/famine, so can you call it intellegence, fast breeding cycles, doesn't imply "god" put it there. But good chemistry, proper mixing of the appropiate star stuff, and the death of many stars already past. So could god be the astronut left behind in the latest suicide attempt from cities in flight?

Re:God made it. (1)

jbmartin6 (1232050) | about a year ago | (#43618959)

Ok, then where is everybody? AKA Fermi Paradox [wikipedia.org] The rare Earth has always been my favored explanation.

Re:God made it. (0)

Anonymous Coward | about a year ago | (#43619259)

Everybody is on their own planet with the same chemicals and rules as here. They're just as far away from us as we are from them, and they won't have anything better than us technology-wise. They can't get here, and we can't get there. Simple as that.

Re:God made it. (1)

tehcyder (746570) | about a year ago | (#43619439)

The obvious answer to the Fermi paradox is that the Earth, while not unique, is unfortunately the first place in the whole universe to develop life.

Just because the universe is much older than Earth doesn't mean that life must have developed elsewhere first.

Unfortunately, this means we may never meet any intelligent alien life, escept in some unimaginably distant future (hundreds of millions of years from now) if we even still exist then.

Re:God made it. (1)

tehcyder (746570) | about a year ago | (#43619129)

The Universe is so large that it cannot possibly be that we are the only life thriving on a planet orbiting a star.

That is emotionally compelling but logically invalid.

Re:God made it. (0)

Anonymous Coward | about a year ago | (#43619293)

I like how science fiction is coloring your (and everyone else's) viewpoint here. The only reason we think there must be life out there is that our fiction has conditioned us to think that. You forget that we have no actual evidence. But only actual evidence counts.

Re:God made it. (0)

Anonymous Coward | about a year ago | (#43617445)

I don't... I can't...

Fry's NOT SURE if troll

Re:God made it. (4, Insightful)

Black Parrot (19622) | about a year ago | (#43617451)

See? We are the only place in the universe that can sustain life.

Great. Now that we've got that established, we can argue over which god made it.

Re:God made it. (1)

macraig (621737) | about a year ago | (#43617615)

Anthony Hopkins, of course!

Re:God made it. (0)

Anonymous Coward | about a year ago | (#43618563)

Heresy! It was Morgan Freeman, obviously.

Re:God made it. (0)

Anonymous Coward | about a year ago | (#43618681)

Titty Sprinkles. (No really, google it)

Re:God made it. (1)

Xicor (2738029) | about a year ago | (#43617453)

we arent the only place in the universe that can sustain life.... there are several other planets that have running water and are about the same distance from their stars. besides.. just because humans cant inhabit planets with larger gravity and hotter temperatures doesnt mean nothing can.

Re:God made it. (0)

Anonymous Coward | about a year ago | (#43618297)

Gullible idiot

Hrm... (-1)

Anonymous Coward | about a year ago | (#43617415)

The most common systems contain one or more planets one to three times bigger than Earth

Err, what?

Let x = size of Earth

1 * x = .... x?

Perhaps they meant two or three times bigger? Or did they mean an order-of-magnitude bigger (doubtful)?

Re:Hrm... (4, Interesting)

Black Parrot (19622) | about a year ago | (#43617443)

Who knows what they meant, but taken literally "one to three times bigger" means

x+x ... x+3x

"one to three times as big" would be

1*x ... 3*x

Being somewhat of the anal retentive disposition, it annoys the hell out of me when someone says "200% increase" when they mean "doubled", which is merely a 100% increase.

(And since this is *very* common, I stay annoyed the hell out of most of the time.)

Re:Hrm... (1)

Cinder6 (894572) | about a year ago | (#43617703)

Most people get % increases wrong; this is why I usually ask people to give it in "x's". Another that's irritating is "twice as cold."

Re:Hrm... (1)

foma84 (2079302) | about a year ago | (#43618011)

So how exactly big is "one time bigger"?

Re:Hrm... (0)

Anonymous Coward | about a year ago | (#43618863)

Twice as big -- x + 1x = 2x. Obviously, it's an awkward way of expressing it.

Twice as cold (1)

amaurea (2900163) | about a year ago | (#43619327)

Coldness is the inverse of hotness, just as slowness is the inverse of being fast. If something is 100 K hot, then being twice as hot would make it 200 K. Its coldness is 1/(100K), and being twice as cold would make is 2/(100K), which corresponds to a temperature of 50 K. Which is exactly what people mean when they use expressions like "twice as cold". Similarly, ten times as slow as 100 m/s would be 10 m/s. This is unambiguous, mathematically well defined, and intuitively understood by most people even without thinking in terms of inverses. What is your problem with it?

Re:Hrm... (0)

Anonymous Coward | about a year ago | (#43619381)

I stay annoyed the hell out of most of the time.

About those colorful metaphors--I don't think you should use them. You don't quite have the knack for it.

Limitation of detection methods (5, Insightful)

Anonymous Coward | about a year ago | (#43617425)

That's because the current methods used to detect exoplanets are biased towards large close in planets. As technology progresses we will get more diversity.

Re:Limitation of detection methods (1)

dadelbunts (1727498) | about a year ago | (#43617437)

Remember when exoplanets were said to be a " Rare Species In Cosmic Zoo"

Re:Limitation of detection methods (0)

Anonymous Coward | about a year ago | (#43619181)

Using this logic, I think it is safe to say that some day we will say, "Remember when we didn't believe God made the universe".....

Re:Limitation of detection methods (1)

Tablizer (95088) | about a year ago | (#43617717)

I would assume they'd at least attempt to take that into account using various statistical extrapolation techniques.

For example, the frequency of bigger inner planets may be much higher than expected based the abilities and limitations of our detection methods. For example, using existing technology, they would estimate that say 1 out of 20 stars analyzed had detectable "big" inner planets if our system was typical. However, if they find 1 out of 5 do, then that suggests there really are more big inner planets out there.
   

Re:Limitation of detection methods (2)

Jane Q. Public (1010737) | about a year ago | (#43617723)

True, true.

But what bothers me is that I have no idea what "one to three times bigger" means.

I understand "one to three times Earth's size", and I understand "two or three times as large" and "twice as big". But I don't understand "one to three times bigger".

I suppose logically, "one time bigger" would mean twice the size. But then "two times bigger" would mean three times the size, and so on. I get the feeling that's not what he meant.

Re:Limitation of detection methods (1)

Artea (2527062) | about a year ago | (#43617915)

I believe we should translate as we would read it out. One Times (size of earth) as 1x earth = same size as earth.

Diversity (4, Funny)

gillbates (106458) | about a year ago | (#43617805)

I would posit that we'd have more diversity if scientists stopped being so conservative about what qualifies as a planet.

Take, for example, the plight of Ceres [wikipedia.org] . Residing somewhere between Mars and Jupiter, it's been called a dwarf planet for quite some time, just because of its immutable physical characteristics. Size discrimination is very real in the physics community, a practice which continues to this day.

Imagine how many more planets we'd be able to discover if we'd just liberalize the definition of a planet. I know it's served us well, but it is time to redefine the term planet to be more inclusive of our increasingly diverse universe. And how, exactly, would this hurt the status of existing planets? I know it wouldn't affect my planet.

And why, exactly isn't Ceres a planet? Because the IAU decided to redefine the term "planet" to exclude it! Such blatant bigotry has no place in a pluralistic universe. We should be ashamed.

Re:Diversity (1)

able1234au (995975) | about a year ago | (#43617881)

We live on planet #3 of 30,000 and i keep forgetting the names of the others.

We will see Ceres soon. Perhaps we won't think much of it after that... i would hardly think of Vesta as a planet.

Re:Diversity (1)

symbolset (646467) | about a year ago | (#43617965)

Oh, no. Once we get a good look at Ceres we're not going to be thinking of much else.

Re:Diversity (2)

able1234au (995975) | about a year ago | (#43617979)

As long as we don't have to look at Uranu....... (oops)

Re:Diversity (1)

amaurea (2900163) | about a year ago | (#43619199)

The classification of Ceres is completely irrelevant to exoplanet searches because the definition used for exoplanets does not include the planet/dwarf planet distinction that is used in the solar system. The reason why you don't hear about Ceres-size planets around other stars is not that people are choosing to ignore them, but that they cannot be detected with current means (actually that only applies to planets around normal stars. Objects even smaller than Ceres have been detected in orbit around pulsars).

Furthermore, even if we could see other solar systems in as much detail as we can see our own, and decided to split their objects into planets, dwarf planets, etc. that does not mean that all the stuff that isn't a major planet would be ignored in any way.

Imagine how many more planets we'd be able to discover if we'd just liberalize the definition of a planet.

You know what? We do discover those objects. And study them. Just as much as we do major planets. Nobody says things like "Oh, I would study object X if only it were a planet. But since it's only a dwarf planet, it is beneath my notice." The one who is being discriminatory here is you, who implicitly claims that only planets count.

Re:Limitation of detection methods (3, Insightful)

symbolset (646467) | about a year ago | (#43617987)

What AC said. Almost all stars have at least one, usually two or three, rocky bodies in the habitable zone. Sometimes they are moons, sometimes planets. But they are almost always there. The exceptions are obvious: stars with stars in that zone (tight binaries), exploded stars, stars that are too young to come steady, Population III stars poor in metals and so on. When we can see them, we will find them. Until then, studies like this that survey observations that could not see such a thing are just a waste of time.

Re:Limitation of detection methods (1)

mrthoughtful (466814) | about a year ago | (#43618223)

mod parent up even higher than 5.

Re:Limitation of detection methods (0)

Anonymous Coward | about a year ago | (#43619073)

Not to mention the optical resolution sucks. I think we can get a pixel or two for a planet if we're lucky. One million times more sensitivity may show better results, but who can make a mirror the size of a planet?

Our best bet for something near that scale may be to carve a large telescope into the moon. Lunar regolith is 21% silicon 13% iron, 7% aluminum, and 6% magnesium (and over 40% oxygen). Silicon can be turned to glass. Both aluminum and magnesium can be used as a backing for a mirror. All elements for steel production are possible to mine, but carbon imports may be necessary.

Earth's moon is the 5th largest moon in the solar system. Ganymede [wikipedia.org] , the largest, is bigger than Mercury, has an atmosphere containing oxygen, has a magnetosphere, and may have a saltwater ocean 200km below the surface. It could prove to be a vital fuel depot and base for exploration missions of the outer solar system after we "get off this rock". It also has 12% lower gravity than the moon.

Could this maybe be because.... (5, Insightful)

Anonymous Coward | about a year ago | (#43617433)

We're still really bad at detecting planets that are NOT bigger than Earth and orbiting much closer to their parent stars? Seriously, whether we use light occlusion or observing the star's wobble, this is the only type of planet we know how to detect.

Turns out if you're color blind, red and green are very rare and special colours.

Re:Could this maybe be because.... (0)

Black Parrot (19622) | about a year ago | (#43617457)

Turns out if you're color blind, red and green are very rare and special colours.

If you're red-green colorblind, that should be "colo[u]r", singular.

Re:Could this maybe be because.... (1)

captainpanic (1173915) | about a year ago | (#43618109)

We are actually pretty bad at detecting small objects that are orbiting our own sun! I agree that our detection methods have a strong bias for larger planets in near orbits to their star. However, it is still interesting to read that Jupiters are less common than Neptune sized planets.

Still, it's a nice article. I didn't know the counter for exo-planets stood at 900 already. Awesome.

Observation Bias (5, Informative)

Anonymous Coward | about a year ago | (#43617465)

I was under the impression that this was agreed to be due to observation bias. That is, it's a hell of a lot easier to find planets bigger than Earth orbiting at frequent, highly periodic intervals than to find anything else.

Re:Observation Bias (5, Insightful)

Thorfinn.au (1140205) | about a year ago | (#43617485)

Using any of the techniques of observation of extra-solar planets it needs 3 orbital periods to confirm a planets existence, with Kepler observatory this means only planets with a period of 1y can be confirmed. Jupiter has a period of 11.9years, so observations of nearly 36 years are needed for this planet and Neptune is 164years, thus requiring observations over nearly 500years, and then for the outer dwarf planets the observation time needs to be over 1.5 millennia. So, obseratvion of 20 years means the search has only started and not that this solar system is weird.

Re:Observation Bias (3, Informative)

TuringCheck (1989202) | about a year ago | (#43617709)

3 is a very conservative minimum - usually more orbits are needed to improve the signal / noise ratio by averaging.

For K averaged orbits the S/N ratio improves by sqrt(K) so detecting planets that cause just small variations drowned in a lot of noise becomes quickly impractical...

Re:Observation Bias (1)

Anonymous Coward | about a year ago | (#43618243)

I just found the original science article and it is actually not saying that our type of solar system is rare. It is saying that solar systems with planets bigger than earth closer to the sun are so common that solar systems without are the less common ones.

To use a car analogy. If you can detect gasoline fumes from 70% of all the cars you see then you know that nongasoline cars are less common even though you can't detect what they are running on :D

Zoo? (-1)

Anonymous Coward | about a year ago | (#43617479)

Ape! Apes wearing clothes!
It's a madhouse! A madhouse!

Downmod me, you damn dirty apes?!?!? The reason no one'll talk to you is because you're a freak!

Good! Rare is many according to the law of big N (2)

G3ckoG33k (647276) | about a year ago | (#43617599)

Good! Rare is many according to the law of big N

Rare?! If only one in a million fits, that would be an enormous amount of habitable planets!

They had examined 900 in detail and and already concluded that a few might fit. Well, it sounds more like one in a hundred, which then would be even more GREAT!

So instead of billions, just millions... (1)

PmanAce (1679902) | about a year ago | (#43617639)

So instead of billions of solar systems like ours, there are just millions. And in at least thousands of those millions, there is probably some poor shmuck like myself posting from their parents basement!

And yet... (2)

huckamania (533052) | about a year ago | (#43617683)

If we stay on this rare planet, we are certainly doomed. It's the nicest place we know of but if we don't get off this rock, we'll probably get killed off by collision with a smaller rock. Or a super volcano... Or Mannian hot air... Or the next ice age... Or our own greed and stupidity.

My money is on the Bransons and Rutans of this world figuring out how to get us into space and someday stay for good. Once someone figures out how to survive in space, there will be thousands hot on their heels. We don't need another Earth. If we can survive long enough to get there, the only reason we'll stay is for variety, not neccessity.

There are more raw resources between the orbits of Mars and Jupiter than exist on Earth. We just need to get there.

Re:And yet... (0)

Anonymous Coward | about a year ago | (#43617693)

Paranoid delusional space nuttery.

Re:And yet... (0)

Anonymous Coward | about a year ago | (#43618205)

Paranoid delusional space nuttery.

You're going to die of old age, QA. And there's nothing you can do about it.

Re:And yet... (1)

Black Parrot (19622) | about a year ago | (#43618875)

Paranoid delusional space nuttery.

You're going to die of old age, QA. And there's nothing you can do about it.

Actually there is, though I hesitate to recommend it.

Re:And yet... (0)

Anonymous Coward | about a year ago | (#43619133)

And no one's living on the Moon, and the species won't exist in a few million years anyways, space or not. Evolution is still happening, you know.

Limitations of Kepler (5, Insightful)

kenwd0elq (985465) | about a year ago | (#43617721)

The problem isn't that there are no planets in more distant orbits; it's that the Kepler Space Telescope is designed to detect occultations, when a planet passes between the star and us. I am frankly ASTONISHED that Kepler has discovered SO MANY planets in so close to the parent star, but a civilization in the Tau Ceti or even Alpha Centauri system would never be able to detect the Earth - because none of our planets ever occult the Sun from their viewpoint.

Look up in the night sky, and imagine those distant (and very hypothetical!) civilizations orbiting those many, many stars and trying to find US.. Using a Kepler-type telescope, ONLY civilizations that are pretty darn close to the ecliptic would be able to detect OUR solar system.

For Kepler to have discovered so many planets, there must be planetary systems around virtually every star out there. There may be a trillion stars in the Milky Way. If only one in a million planets host anything even remotely resembling "life", there must be a million planets with some form of life.

Re:Limitations of Kepler (3, Informative)

bruce_the_loon (856617) | about a year ago | (#43617991)

Precisely. Kepler's been up and observing for 4 years now. Since it hunts for occultations, the scientists can only be certain that observed planets are alone out to a 4 year orbit, which excludes anything outside of Mars in our system. And that is if the system is aligned so that the orbital plane is correctly positioned for Sol-visible occultations.

For a star where Kepler has observed something, they can only say there's no planets inside 4 year orbits, everything else is speculation. For a star where nothing has been observed yet, they can't say anything with certainty.

Things that keep one awake (1)

Tablizer (95088) | about a year ago | (#43617831)

I wonder if any other planet has Microsoft Bob also

WYSIATI (2)

mha (1305) | about a year ago | (#43617837)

The (Nobel price winning) psychologist Kahnemann calls this phenomenon "What You See Is All There Is" - and he detected in the "experts", not in space.

Re:WYSIATI (2)

able1234au (995975) | about a year ago | (#43617889)

Winner of the Nobel Price is Right?

Re:WYSIATI (0)

Anonymous Coward | about a year ago | (#43617949)

Winner of the Nobel Price is Right?

Seems very probable to me, without reading up on said Nobel Price winner, that he might have employed irony [wikipedia.org] here.

Re:WYSIATI (1)

mha (1305) | about a year ago | (#43617985)

I also forgot an ENTIRE WORD ("it"). I'm glad some people are able to concentrate on what's important.

Every single exoplanet is GREEN BLACK! (0)

Anonymous Coward | about a year ago | (#43617879)

Anyone wearing night googles to study exoplanets could tell you that.

The fact is (1)

Sla$hPot (1189603) | about a year ago | (#43617919)

We can't see much with our telescopes.Twenty years ago we couldn't detect the planets that we can today.
In twenty years or so from now we will be able to detect even smaller planets that we can today. I bet.

Detection bias? (1)

allcoolnameswheretak (1102727) | about a year ago | (#43618185)

Most exoplanets are much bigger and closer to the sun than Earth is... incidentally, these are the kind of planets that are most easily detected.

'nuff said.

Detection bias? -Absolutely! (1)

Herve5 (879674) | about a year ago | (#43618453)

Obviously it's not "most planets are bigger than Earth", it's very exactly "our present detection method being a measure of star movements due to the planet presence, we only see enormous jupiter-like things for now".
How to say it politely?
"I hope the OP summary is, er, too concise, otherwise this just means Hawaii climate turns the scientists silly..."

what we see and, what there is... (1)

Mysund (60792) | about a year ago | (#43618245)

As far as i know, the closer a planet is to its sun, the greater the signal footprint we get. So it cant be a big suprise that we havnt found so many minor planets like earth, when we also know that bigger and closer-orbiting planets exists.

In other news (1)

argStyopa (232550) | about a year ago | (#43618625)

...scientists take a measurement that's known to be valid in only a microscopic fraction of observables (ie, systems that happen to have their ecliptic in line with ours, and have an orbital period so far of 1 year) and base broad, sweeping conclusions about the entire universe on them.

These guys are almost as bad as anthropologists, who'll build an entire career 'interpreting' facets of a who civilization extrapolated from a half-dozen potsherds.

Free ArXiv version (3, Informative)

amaurea (2900163) | about a year ago | (#43619087)

The actual article is much better than the one linked in the story. A version very close to the one published in Science can be found here [arxiv.org] , at the public preprint archive (arXiv). The article should be relatively easy to read even for non-scientists. Note that our knowledge of the distribution of planets is marred by the biased sample we have access to: It is much easier to observe planets if they are close to their parent star, and heavy. Most of the statistics provided in the article attempts to correct for this bias, so we can say pretty confidently that small planets are much more common than large ones*. But the other claim in the summary, that most planetary systems are much more compact than the solar system, doesn't seem to be supported in the article itself. But perhaps I missed something.

Anyway, the Science article is readable, and if nothing else the figures are quite interesting.

God did it (0)

Anonymous Coward | about a year ago | (#43619101)

There said it. Total troll post.

Nothing to see here. Ignore us, Earth isn't one big reality show that we use for our amusement.

Call me silly (1)

SengirV (203400) | about a year ago | (#43619183)

Isn't there something to be said for sample size here? We've had the ability to "easily" see large planets. We've discovered that there is a strange(to us) phenomena known as "Hot Jupiter". But other than that, we have found only relatively large planets up to this point. Each of those systems with large planets may also contain smaller planets as well.

You can't prove a negative, but that appears to be what they are doing. Since we don't have the tech to discover systems like our own, we MUST be rare.

Not so silly... (1)

rraylion (1406761) | about a year ago | (#43619371)

This is a comment from a scientist that I can only hope was taken out of context...

The most common systems contain one or more planets one to three times bigger than Earth, all orbiting much closer to their parent stars than Earth circles the sun, says astronomer Andrew Howard, with the University of Hawaii."

Of the planets we have found, from observation with Kepler mission are the ones with the shortest revolutions. Basically Kepler counts how many times the star dims and looks for a pattern ... every 90 days -- every 180 days... If Kepler was in Alpha Centauri it would not have been in operation long enough to find Earth yet if it was look directly at the Sun. It need up to 4 occurrences to be sure it has found a planet... it started in May 19 2009 -- If we passed in front of the Sun on the 19th --- it would not 'find' Earth until two week from now. Kepler has not been in operation long enough to find Earth yet ... so the claim that most planets are orbiting closer to the Sun than Earth is because it will be in the next two years that the planets that orbit with a similiar period to Earth start to show up... It the MAIN reason the program was extended to 2016 ... That way we will see the Earth like orbits and a few Mars like orbits.

Re:Call me silly (3, Insightful)

amaurea (2900163) | about a year ago | (#43619399)

You and a whole horde of other slashdotters have had the idea of ease-of-measurement bias - a large fraction of the posts on this article mention it. Thankfully, the researchers who study these planets have also thought of it. They have even measured how large it is, and corrected for it. One result of this is that even though we see a large number of hot jupiters, we know know that planets get more common the smaller they are. That is actually one of the main points of the article. I guess this goes to show how many actually read it.

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