Earth-Like Planets May Be Common Outside Our Solar System, Scientists Discover (vice.com) 52
Scientists have directly observed the rocky guts of exoplanets, which are worlds from different star systems, by watching the fallout of these objects crashing into the corpses of dead stars. From a report: This mind-boggling technique has revealed that exoplanets are similar in composition to planets in our own solar system, implying that worlds like Earth may be plentiful in our galaxy, according to a study published on Thursday in Science. "It's pretty cool because this is really the only way to measure the geochemistry of exoplanetary bodies directly," said lead author Alexandra Doyle, a graduate student of geochemistry and astrochemistry at UCLA, in a phone call. Co-author Edward Young, a professor of geochemistry and cosmochemistry at UCLA, added that the study represents "the first time such an advanced way of looking at the geochemistry of these bodies has been used," in the same call.
We are living through a golden age of exoplanet discoveries. Thousands of exoplanets have been detected, including an Earth-sized world orbiting the closest star to the Sun. But it is still extremely difficult to capture details about the interior composition and dynamics of these worlds. Unlike other planetary properties such as mass or atmospheric composition, a planet's geochemistry cannot be deduced just by looking at an object passing in front of its host star. White dwarfs, as it turns out, can help plug this information gap. These objects are the remains of stars that have blown up and collapsed into tiny, dense spheres about the size of Earth (our own Sun will embark on this transition in about five billion years). The pyrotechnic deaths of these stars scramble the orbits of many objects in our solar system, such as asteroids and planets. Some of these worlds may end up hurtling toward the star's posthumous white dwarf, which tears them apart over the course of about 100,000 to one million years.
We are living through a golden age of exoplanet discoveries. Thousands of exoplanets have been detected, including an Earth-sized world orbiting the closest star to the Sun. But it is still extremely difficult to capture details about the interior composition and dynamics of these worlds. Unlike other planetary properties such as mass or atmospheric composition, a planet's geochemistry cannot be deduced just by looking at an object passing in front of its host star. White dwarfs, as it turns out, can help plug this information gap. These objects are the remains of stars that have blown up and collapsed into tiny, dense spheres about the size of Earth (our own Sun will embark on this transition in about five billion years). The pyrotechnic deaths of these stars scramble the orbits of many objects in our solar system, such as asteroids and planets. Some of these worlds may end up hurtling toward the star's posthumous white dwarf, which tears them apart over the course of about 100,000 to one million years.
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The question is, why we are special
I reject this notion. It's just back to the old "man at the center of the universe" concept usually associated with religious drivel. One can't only consider space but also time as well. It's quite possible that civilizations rise and fall all the time. However for them to exist as neighbors at the same time - that is more unlikely. It's truly staggering to wrap your mind around billions of years worth of time - both in the past and towards the future. A lot can happen in several billion years. Look at what
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But as for now, we are special in the sense that we are members of a set of the ordinality of 1. There is no other place out there we know, where complex chemistry keeps up vast structures able to sustain themself and replicate,
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The problem is a lack of observations of those exoplanets precise enough to rule out both life and intelligent life. We haven't been able to do that for a single exoplanet, let alone the moons of Jupiter and Saturn in our own solar system.
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Hell, we haven't even ruled out the possibility of life on Mars, either fossil or present-day living, and we have several satellites in orbit and rovers on the ground.
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We have pretty clearly ruled out intelligent civilizations on Mars. But we haven't ruled out an intelligent civilization living inside Ganymede or a bunch of other moons.
Re:How to convince a scientist that we are special (Score:4, Insightful)
You may want to refer to the Drake equation. A product of.
The average rate of star formation in our galaxy
The fraction of those stars that have planets
The average number of planets that can potentially support life per star that has planets
The fraction of planets that could support life that actually develop life at some point
The fraction of planets with life that actually go on to develop intelligent life (civilizations)
The fraction of civilizations that develop a technology that releases detectable signs of their existence into space
The length of time for which such civilizations release detectable signals into space
Now, we are only dealing with the first points.
Related to that are the Fermi paradox and the great filter.
The Fermi paradox is that we can't see any intelligent alien civilizations despite the galaxy being so big and the universe even more so.
The great filter is one explanation. That is the step in the Drake equation is the limiting factor.
We know it is not the number of planets, so it may be that truly inhabitable worlds are rare, that life is rare, that intelligence is rare, that technology is rare, or that technological civilizations don't last long. We hope it isn't the last one.
As a result, every discovery that points out that intelligent life shouldn't be rare is actually bad news, because it means that the short life of civilizations is more likely to be the limiting factor.
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The great filter is one explanation. That is the step in the Drake equation is the limiting factor. We know it is not the number of planets, so it may be that truly inhabitable worlds are rare, that life is rare, that intelligence is rare, that technology is rare, or that technological civilizations don't last long. We hope it isn't the last one.
I think you missed one: that civilisations tend not to release detectable signs of their existence for long. Not because they've wiped themselves out, but perhaps because they learned the same lessons we did about satellite communication, fibre optics and so forth.
As a corollary to the Fermi paradox it can be interesting to look at things from the opposite direction: would an alien society on a planet orbiting, say, Pollux notice us?
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The better the encryption... the better the compression.. the less we leak into the universe as identifiable.
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One by one potential great filters are getting knocked down. Planets aren't rare. Planets in the Goldilocks Zone aren't rare. Earth-sized planets aren't rare.
At this point there's no reason to think that planets capable of supporting water-based are rare. And we know amino acids are all over our solar system, so no reason to think they're rare.
Once you have intelligent life, most of the proposed "great filters" just don't hold up to close inspection. Most require some assumptions about uniform alien ps
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You've missed one...the other possibility is that intelligent life takes a very very long time to get started...life had already been on earth for billions of years before we showed up. It may be the case that some intelligent life evolved 15 million, 70 million, 136 million, 1 billion, or even billions of years ago on other planets and for various reasons didn't stay around long enough for us to detect them. It's not just that we have to calculate the odds of intelligent life exisiting...it may be the ca
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That's the thing: intelligent doesn't have to still be around to see it, once it becomes a Kardashev Type II civilization, unless there's some magic technology we haven't found yet that totally changes what such a civilization would look like.
One civilization that flooded the galaxy with Von Neumann probes would mean we should be able to find the relics in our system (admittedly, we're just starting to look). If intelligent life isn't vanishingly rare, and Dyson swarms aren't a vanishingly rare outcome for
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walk through this with me
First, lets assume other life started and advance biologically and technology similar to us, just for the sake of presenting what I am pointing out.
So, as a race, we are looking for radio frequencies for signs of intelligent life beyond our solar system. When did we become advance enough to create this tech that others would find? Lets use the round number 100 years.
According to http://www.solstation.com/star... [solstation.com] there are 76 type A stars within 100 light years.
So assuming there is l
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How many billions and billions of Earth like planets do we have to confirm and still not find any sign of intelligent life before scientists have no choice but to finally recognize that humanity is unimaginably special?
Well considering that we've only recently been able to start detecting exoplanets, I think it's a bit early to start tossing in the towel for no life outside the Earth. Heck, we can't even positively search for life that might have existed before on Mars or Venus and that's next door in comparison. I'd say we're still in the early game for the search for life but that's overselling it. If you could put mankind's search for life in the context of a human beings life cycle, I'd say we were pretty much born
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We have no idea how common intelligent life is in the galaxy. We just know they're not talking to us using technology we understand, and they didn't leave any obvious relics on Earth or the Moon.
We also know, and this is a real stumbling block, that Kardashev Type II civilizations either don't exist, are incredibly rare, or take some form other than the obvious (Dyson swarms), because of some technology we don't have a hint of.
At this point it's far to early to say whether intelligent life is very rare, or
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We just know they're not talking to us using technology we understand
Or maybe they tried talking to us thousands of years ago but we weren't in any position to listen let alone reply, and now they've given up and decided there's no intelligent life out there. Maybe they will reconsider if they start hearing our broadcasts in 500 years or so...if they are still around and in a position to listen/reply.
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How many billions and billions of Earth like planets do we have to confirm and still not find any sign of intelligent life before scientists have no choice but to finally recognize that humanity is unimaginably special?
The Great Filter may eliminate us momentarily. How special will we be then?
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At least a few more than the current count, which is still "one", in case you haven't been paying attention.
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Probably neither is our GREED, our galaxy all ours no other beings in it, every sun every planet, there would be quite a few very, very primitive stone age etc species, just as greedy as us, their galaxy all theirs, every star in the sky (no planets out there yet for them, but the entire galaxy is theirs as are their primitive Gods, all theirs serve only them in the ENTIRE universe, seriously the ego, yeah sure stone age alien, you sky being wish machine serves only you in the entire universe). So painfully
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I recommend the little blue pills next time you get in front of a keyboard.
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Literally, JUST ONE OTHER and we are in no way unique
On the other hand... (Score:3)
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Mercury is too small to be called Earth-like. Even if it was in the habitable zone it wouldn't have held an atmosphere. Mars didn't have an atmosphere for very long.
We haven't found that many exoplanets in the right size range (bigger than Mars, but smaller than 2 x Earth) because they are a lot harder find than Gas Giants.
It is likely that there are more Europa-like moons around some of those Gas Giants than there are suitable Earth-like planets within the habitable zone. Especially as dmaller stars habita
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... the planets in our Solar System which are Earth-like, e.g. Mercury, Venus, Earth itself and Mars, are quite different from each other. Just because the newly discovered exoplanets are Earth-like, doesn't mean that they are inhabitable for the likes of us. And if we discover more about those exoplanets, we will probably at first discover a hundreds more ways to be totally different from Earth.
"Earth-like" is not "exactly like Earth."
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It's like pointing out most heavily burned supper tastes similar.
See? Earth is not unique. (Score:2)
So all earth supremacists can shut up now!
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We have the Chosen Planet; all other planets are shit-holes full of 3rd-rate losers, believe me. I kinda like Mars because it's a beautiful orange, but it's a bit small. Size is for winners. We should build a Dyson Wall around Earth and make Jupiter pay for it so those scaly ugly Lizardians don't get in. Worst Aliens Ever, scored 3 zeros in the latest Orion poll. Really bad skin. Plus they keep trying to take the Tribbles on my head back home. My tribbles love me, everyone knows it, I never ever yell at the
Veeger knows (Score:2)
Link is to wrong article. (Score:2)
Well DUH.... (Score:2)
Did prices of land on Earth already plummet? (Score:2)
Here is the correct article link (Score:1)
Another thing that's common out there ... (Score:2)
... is the cold.
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Sorry, low hanging fruit.
Terminated (Score:2)
Planet: Good. I hate long waits.
C-3PO: You will therefore be hurtled toward the star's posthumous white dwarf.
Planet: Doesn't sound so bad.
C-3PO: In its orbit, you will find a new definition of pain and suffering, as you are slowly torn apart over the course of about 100,000 to one million years.
Planet: On second thought, let's pass on that, huh?
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Discover? (Score:2)
They didn't discover shit. They're CONJECTURING.
Re: Discover? (Score:1)
Not if the Rare Earth Hypothesis is true (Score:2)
The Rare Earth hypothesis argues that the origin of life and the evolution of biological complexity such as sexually reproducing, multicellular organisms on Earth (and, subsequently, human intelligence) required an improbable combination of astrophysical and geological events and circumstances.
The Rare Earth hypothesis is a possible explanation for the Fermi Paradox [wikipedia.org].
There are TRILLIONS of Planets (Score:4, Interesting)
Back in the early days of theorizing about extraterrestrial life, the discussions about the Drake Equation covered all the various factors to consider in how likely extraterrestrial life might be. It was always assumed that planets were unlikely to exist.
Now we know differently. The Kepler Space Telescope used an "occultation" method of discovering planets; we could see the tiny decrease in a star's light as a planet passed between the star and the Kepler. THINK about that for a moment. What other star systems might be able to discover Earth by that method? Look up into the sky, and follow the constellations of the zodiac, those constellations on the ecliptic. Now look for some stars that are EXACTLY on the ecliptic. Damned few - but those are the ONLY systems that might be able to detect the Earth's transit across the Sun from their perspective.
Back to the Kepler; the planets that we've detected are the ones on THAT system's ecliptic! Given that star systems can form in ANY orientation, there should be very few systems where THAT system's ecliptic matches - exactly - the Earth. And how many planets has Kepler discovered?
THOUSANDS. The only reasonable assumption is that almost EVERY star has planets, and maybe LOTS of them. How may stars in the Milky Way? Every time our telescopes get better, we discover even more stars. There are probably a trillion stars in the Milky Way, and on average, there's probably at least that many planets.
Given that many planets, there's certainly a FEW similar to the Earth. There may even be some within 100 light years of Earth. But those systems ecliptics don't intersect the Earth, so Kepler doesn't see them.
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To give this a little more context, from wikipedia:
I couldn't quickly find a count of how many systems those (potential) exoplanets are distributed across.
But, yes, that's ~1% of observed stars found to have at least one
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The article link is incorrect (Score:1)
I think this story is pointing to the wrong article; the correct one is apparently at https://www.vice.com/en_us/art... [vice.com].
Should we assume that none of the previous commentors read the source article?