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Our Solar System: Rare Species In Cosmic Zoo
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."
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.
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.
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.)
Sheesh, evil *and* a jerk. -- Jade
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.
Sheesh, evil *and* a jerk. -- Jade
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.
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?
Sheesh, evil *and* a jerk. -- Jade
Two fun facts:
1. In TOS, it was somewhat legitimate science fiction 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 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, although many were softened: the 20s gangster planet was created by accidentally leaving a history book behind, and the Nazi episode (TM) 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. 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.
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To be fair, TNG did explain why (most) aliens were humanoid in the episode The Chase.
If you can't convince them, convict them.
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.
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?
Sheesh, evil *and* a jerk. -- Jade
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. 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.
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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 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, which point to evidence of life.
Views expressed do not necessarily reflect those of the author.
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.
If Pandora's box is destined to be opened, *I* want to be the one to open it.
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.
ACs don't waste your time replying, your posts are never seen by me.
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, 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.
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.
Once someone figures out how to survive in space, there will be thousands hot on their heels.
Why? I really don't see that there are going to be "space miners" hacking out asteroids with picks and shovels. Surely it would be easier (and cheaper) to get robots to do it all?
And apart from harvesting raw materials, who the fuck else would want to live in space for more than a few months until the novelty value wore off?
To paraphrase Samuel Johnson on being in the Navy: no man will live in space who has contrivance enough to get himself into a jail; for being in a spaceship is being in a jail, with the chance of being asphyxiated, dying of radiation poisoning or irreversibly altering your muscles and organs. A man in a jail has more room, better food and commonly better company.
To have a right to do a thing is not at all the same as to be right in doing it
Well until we actually observe other alien life the scientific assumption should be that most life is like ours, that ours is the path of least resistance, the optimal path that all life takes. I think we should be open to it being radically different, however until we observe anything to the contrary, it is all just so much speculation. It could be that some life is so radically different that we may have a hard time recognizing to even observe it. It could be that we are the life oddballs, and most take another path. Who knows. However at this time the most rational response would be to surmise that at least at this time, life is likely similar to ourselves.