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Kepler Investigator Says 'Galaxy Is Rich In Earth-Like Planets'
astroengine writes "In a recent presentation, Kepler co-investigator Dimitar Sasselov unexpectedly announced news that the Kepler Space Telescope has discovered scores of candidate Earth-like exoplanets. Not waiting for the official NASA press release to announce the discovery, Sasselov went into some detail at the TEDGlobal talk in Oxford, UK earlier this month. This surprise announcement comes hot on the heels of controversy that erupted last month when the Kepler team said they were withholding data on 400 exoplanet candidates until February 2011. In light of this, Sasselov's unofficial announcement has already caused a stir. Keith Cowing, of NASAWatch.com, has commented on this surprise turn of events, saying it is really annoying 'that the Kepler folks were complaining about releasing information since they wanted more time to analyze it before making any announcements. And then the project's Co-I goes off and spills the beans before an exclusive audience — offshore. We only find out about it when the video gets quietly posted weeks later.' Although Sasselov could have handled the announcement better (and waited until NASA made the official announcement), this has the potential to be one of the biggest astronomical discoveries of our time — so long as these Earth-like 'candidates' are confirmed by further study."
can we just start calling them 'M' Class ?
Seems like the only info released was a distribution of planet size. Without planet composition, I would describe these as Earth-size, not Earth-like. It's a little early to get excited.
There are more things in heaven and earth than are dreamt of in your philosophy.
Is the Kepler team dysfunctional, or do they just enjoy pissing on one another?
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Is interstellar space travel feasable?
If there is no faster then light method of travelling possible, then there are unlikely to be any visitors ever. End of story.
And while 400 planets sounds like a lot, in the milky way it isn't much at all, especially if you consider the short timespan that humans have been capable of even seeing into deep space let alone make their presence known. And there are countless disasters that can wipe out a civilization.
There are aliens out there, in the deep vastness of space and time. Just as somewhere there is a smart intelligent girl that totally digs D&D. To bad she was born 200 years ago.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
I agree. Water presence? Temperature within habitable range? At least a primordial atmosphere? Not sure if Kepler is the right tool to collect that kind of data, but to call them "earth like" seems premature. Granted, if the size approaches that of earth chances are they're rocky, solid planets, but that's it.
My bet is that the vast majority of those planets have run away from having a habitual environment by turning into planets like Venus or Mars.
I'm wondering how close to Earth's size a planet has to be to be an "Earth sized" planet. Venus is an Earth sized planet, and as you say, is in no way habitable. Mars isn't that much smaller, but has little atmosphere and no magnetic field; I don't see how life could exist on a planet without a magnetic field to keep stellar radiation out.
There are a whole lot more variables than size to consider.
we aren't getting any visitors
Maybe Doctor Fielgud and his colleagues will figure out that a "moon sized double planetoid" can harbor life if it has an iron core, and that oxygen isn't a poison to all species. And maybe the NASA people will start looking at satellites of gas giants around other stars. Meanwhile, that bit of fiction I linked gives a possible explanation as to why nobody's calling. Here's another bit of fiction with an alternative suggestion.
Free Martian Whores!
Kepler needs 3 transits to confirm a planet, so given that it's only been up there since March 7, 2009 any planet around the same distance as earth will only have had 2 transits max.
It's exciting that there are so many candidates but I guess NASA doesn't want the embarrassment of getting everyone all excited then having to hugely backtrack on the number if some turn out to be something else.
It's really sad that a discussion about the possible detection of Earth-sized planets around other stars is dressed up in "it's our data and we want to publish first" and stuff like that.
Humanity will, one day, pay dearly the fact that scientists are forced to fight for resources...
Anyway, this is interesting news. If computers were considered "the revenge of the nerds", I'm curious what the next few years will be called.
new sig
My bet is that the vast majority of those planets have run away from having a habitual environment by turning into planets like Venus or Mars.
So you're suggesting that they have an occasional atmosphere? I don't know. Usually, once a planet gives up its atmosphere habit, it doesn't go back.
I agree. Water presence? Temperature within habitable range? At least a primordial atmosphere? Not sure if Kepler is the right tool to collect that kind of data, but to call them "earth like" seems premature.
Exoplanet spectroscopy has been done, but is a very new science and extremely difficult. And first, we have to be looking at a specific planet with specific instruments.
Kepler, on the other hand, is continuously monitoring a region of the sky and some hundreds of thousands of stars for signs of planets. It detects planets by the "transit method", which means you watch all the stars, and see if any of them dim slightly. You keep watching and if you see it dim again, you might have found a planet (rather than a one-time passing object between us and the star). To be fairly sure it's a planet, you need to see a third dimming with the same time delay as between the first two, showing that it's periodic. Ideally you want to see a 4th event to confirm, but 3 is good enough to call it a candidate -- or maybe they say candidate after 2? I'm not sure.
Note that this means Kepler only sees planets whose orbits happen to be about "edge on" from our perspective. So there could be many systems that Kepler simply can't see -- and given how many it has seen, I think it's safe to say that there are many such systems.
Anyway, from this data, Kepler can figure out the approximate orbital distance and mass of the planet. That's it. You can estimate temperature from proximity to the star, too.
Personally, given Kepler's limited-but-awesome capabilities, I wouldn't mind them saying "earth-like" simply to describe roughly earth-size planets that are in the habitable zone of their star. But I doubt that's the case for most of these, since Kepler has only been running for half a year, and for Kepler to detect something in an earth-like orbit around a Sol-like star, it would take between 2 and 3 years of observation. The only planets Kepler can find up to this point are ones that orbit closely to their star. So most of these are not going to be in the habitable zone.
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It's great that we can now detect Earth-sized planets, but it's starting to look like Jovian moons are a more common life-friendly environment. In our solar system alone there are three, possibly four moons of Jupiter and Saturn that may be able to support life.
Since the moons get most of their heat from the gravitational pull of their planets rather than from their star, they aren't dependent on getting lucky in the narrow "Goldilocks Zone" of a system.
It may be that aquatic, vent-feeding moon ecosystems make up the vast majority of life in the universe, and photo-synthesizing, dry land ecosystems like ours are the rarity.
Anyway, it could be that Earht itself is a borderline planet for life [harvard.edu], just big enough for plate tectonics (something which Venus lacks, and which probably contributed greatly to its conditions); maybe even slightly too small in itself, but was pushed into habitable range by the collision with Theia (the collision that spawned the Moon)
If you look at Earth objectively, we could be living on what so many sci-fi stories like to use as examples of 'prison' planets. Highly hostile worlds which seem wholly unsuitable for life.
Earth:
Corrosive Atmosphere - High % Oxygen
Acid oceans (or base depending on your POV)... H+ OH-
Biologically active - We let biology run rampant everywhere, bacteria, virii, prions
Wild Temperature fluctuations - Denser atmospheres = temperature stable at a set altitude.
It would be interesting to go to an alien planet, and find out we were the ones adapted to an incredibly hostile environment.
Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
Wrong. Kepler only sees close in earth sized planets, with almost no exceptions. Even though it's looking at the same area over a long time.
The reason for this is that for Kepler to see a transit of an earth sized planet, said planet has to occult the star; which in turn means that the planet's orbit has to lie on a plane defined by us and the target star, within a margin of error defined by the planet's diameter against the cone defined by the star at one end and the telescope at the other, which, with an earth like planet, is damned small.
So the further away an earth sized planet gets from its star, the less likely you are to spot it, even with just the slightest deviation for the orbital plane. The consequence of this is that earth sized planets are spotted close in, and basically nowhere else except against extreme odds. Larger planets are spotted because the orbital plane can be significantly more tilted and still result in occultation.
And, even when you *do* spot the earth sized ones that aren't close-in, you still can't tell much about them. They might be like Venus and boil metals, or they might be like mars and freeze your butt off, or anywhere in between, and even if you could tell *that*, you still wouldn't know if they were supporting life.
So again, we're back to needing an optical telescope that can actually resolve the planets, see clouds, continents, etc. Long baseline, multiple aperture, etc. We should do it ASAP. Just keep firing units up there until we have a huge array over millions of miles. Now that would be a telescope worth having. No single aperture instrument is going to tell us anything really interesting about any planet outside our solar system. All they see are indirect hints.
I've fallen off your lawn, and I can't get up.
No, sir, I am not.
Briefly, the resolution achievable using interferometry is proportional to the observing frequency and the distance between the antennas farthest apart in the array. In space, the distance between the antennas, the number of antennas, and the size of the antennas are all matters of raw materials, no more. Once we can manufacture *in* space using materials gleaned from asteroids, there's hardly any limit at all to the size of the synthesized aperture.
The only limitation is the usual one - the data is as old as it is distant.
Believe me, pal, we haven't even begun to construct telescopes of the capabilities our current technologies can enable. We're just putting the money in incredibly stupid places. As today, we just stuffed another fifty nine billion dollars down the Pentagon's automated money disposal. Not to mention the 8.7 billion they "lost."
I've fallen off your lawn, and I can't get up.
Isn't our solar system's ecliptic plane closely aligned with the galactic plane?That's what I remember from the last time I actually looked at the Milky Way up in the sky, anyway.
No, it's actually close to perpendicular. Earth is tilted relative about 30 degrees to the solar ecliptic, still well off the galactic plane. That's why the Milky Way kinda goes diagonally in the sky, and the planets usually don't appear in it.
I had always assumed this was for the same reason that the plane of rotation of most of the planets are aligned with their planes of revolution around the sun...
It is very similar. Think of the planets as systems orbiting the sun much like the solar system is relative to the galaxy. Overall the planets orbit in the same plane around the sun since the planetary system is drawn towards the solar plane and the overall angular momentum. Each planetary system though has its own angular momentum and rotation plane. Some are wildly skewed from the solar plane. For the moons around the planets, the planet is the dominant source of gravity. Just like for the planets, the sun is dominant and the tug towards the galactic plane is very tiny.
I'm not sure if there's any bias at all, but having other star systems appear edge on to us is more or less a matter of chance. So of all the stars Kepler is looking at, only a small fraction of planets are even possible for it to see. Which makes the number it has already discovered that much more amazing.
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