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Earth to...Earth? Are you there?
jasamaman writes "So far all the planets found outside our solar system have been gas giants. So they are not habitable, and couldn't really hold life as we know it. But "planet hunter" David Charbonneau is looking for another planet just like Earth, and claims that astronomers are "very close"."
How the hell could he know that we are "very close" to discovering anything?
Did miss cleo tell him?
I know I'm going to hell, I'm just trying to get good seats.
I see the pointy that any further information about space (even out of our solar system) is useful, but what would we do if we found an earth-like planet?
It is expensive and time consuming to send a probe to Mars, would we really want to investigate this far off planet before we properly explore our own solar system? And put the money in when the results may only come back years after we are all dead? Nope.
"None are more hopelessly enslaved than those who falsely believe they are free." -- Goethe
PQ: How long will it be before scientists might be able to study the atmospheres of Earth-like planets around other stars?
Charbonneau: That's much more difficult. We are close to being able to find Earth-like planets. But it may be decades before we are able to study their atmospheres.
Just close. How close? Well, if you're used to measuring distances in parsecs, 'close' can be quite a bit away, especially as the lad seems fairly young yet. He'll have plenty of time to paddle around, swigging brewskis and gazing at the sky. Good luck to him, I say!
Money for nothing, pix for free
Until the launch of "Darwin" by the ESA, (pdf link) it is unlikely that we will be able to detect earth-like planets. We still cannot detect Jupiter sized worlds at this point in time.
Just you're average nitpicker.
The sun of our solar system contains more than 99,9% of its mass. Of the remaining 0,1%, most is of the megaplanets like Jupiter and Saturn. Jupiter alone has around 500 times the mass of Earth. Habitable plants are thus incredibly, incredibly small compared to their suns or compared to gas giants. Given the limited funding (forget space, we need missile defense!) we can be happy that we can detect gas giants.
well, we do need some place to evacuate to if the Vogons come to buildt an interstellar bypass and destroy the earth in the process.
Lets find 42 alternative planets earth
We're close? You can't just ignore the fact that earth like planets are 10000 times harder to find, simply because they're 10000 times smaller than the gas giants. The truth is that our telelscopes just aren't there yet. The only proof they'll find will be inferrable from what they can see. For example, if large planet's movement is regularly affected in such a way as to suggest a smaller planet's interferance. At this point and time we do not have either the tools or the technizques that we'll need to identify distant planets, all we can hope for is that a few shots in the dark will pay off.
have recently determined that amino acids (protein building block molecules) are formed in a vacuum which would perhaps mean that most life would be formed on the same basis as we are, perhaps it would be easier to look for old radio transmissions and TV-signals as SETI does. Have the people at SETI ever done any modelling to see what our old TV-signals would look like 10 light years from earth?
,winds and life in general.
Another thing that might be vital to life on earth might simply be the fact that we have such a large moon acting as both a shield to a lot of asteroidal bombardment and as a planetary motor for tides
PQ: On a personal note, what do you like to do in your spare time?
4 40990534471
Charbonneau: I find home beer-brewing very satisfying.
David this one's on me!
http://beer.trash.net/beerget.php?yourbeer=101783
good luck on your quest buddy.
"It was penguin lust...at its worst." --someone
There are a number of ways Earth-sized planets could be discovered fairly soon (within the next 5-10 years). There are several planet-finding satellites to be launched. The Hubble would also be capable of detecting an Earth-sized planet passing in front of a star.
The real trick is finding the proper conditions. First, we need to find an extra-solar system in which Earth-sized planets exist. It's now believed that these are fairly few and far between. The reason is that a vast majority of the gas giant systems we've discovered so far have their gas giants in either really close orbits to their stars, or are highly eliptical with passes close to their stars. In these situations, Earth-like planets would likely be tossed into their stars, or more likely, tossed into open space, by the gravitational effect of the giants.
So, what you need is giants that live fairly far out (like Jupiter and Saturn). These appear to be about 1 out of 50+ systems. So, out of this 1-2% of systems, we then need to find ones with orbital planes that are parallel to our angle of view of those systems, and catch the Earth-sized planets passing in front of their stars.
Asking for all those conditions to line up is a pretty tall order, so it's unlikely we'll catch such an event in the next 5 years. My personal opinion. A large breakthrough may change that, and that's possible as well. After all, look at the discovery of extra-solar planets. It was a breakthrough idea that led to a sudden discovery of many of these systems, without a real technilogical breakthrough.
That's true. Astronomers are very close. However, where the hell all these planets are is quite another matter...
Cheers,
Ian
about a year and two days ago?
I wonder if we tuned into another planet's radio wave, if we'd be able to watch their soap operas. I watch soaps for 1/2 a day here on Earth, but wouldn't it be great to watch The Alien and the Cybernetic too? Or maybe we'd get to know them by watching their version of Sally Jesse Rapheal?
"I only speak the truth"
Karma: null(Mostly affected by an unassigned variable)
2) We do not know how non-carbon based life works, develops or even if it is possible. We don't have experimental evidence.
3) Developing a scientific hypothesis requires that you know what you are talking about and have at least some experimental evidence that suggests that we need another hypothesis.
Hence, we cannot speculate on the non-carbon based life -- at least scientifically.
is very very limited. It is debatable whether we know of even two examples of life. All life on earth appears to have a common ancestor and is largely identical. We might know something about artifical life, but it is very limited and highly questionable. Man, Carl Sagan should be prerequisit reading. 1977, that's when Carl Sagan and Edwin E. Salpeter wrote their famous paper of "floaters", "hunters" and "sinkers". If you havnt read it, you are not a part of the conversation. Go buy a copy of Cosmos and get some humility. We're a speck of sand on a beach of stars and some among us thing we know something about life in the universe?
How we know is more important than what we know.
"Particles, Environments, and Possible Ecologies in the Jovian Atmosphere" by Carl Sagan and Edwin Salpeter, Astrophysical Journal Supplements, vol 32, 737-755, 1976.
The eddy diffusion coefficient is estimated as a function of altitude, separately for the Jovian troposphere and mesosphere. Complex organic molecules produced by the Ly alpha photolysis of methane may possibly be the absorbers in the lower mesosphere which account for the low reflectivity of Jupiter in the near ultraviolet. The optical frequency chromophores are localized at or just below the Jovian tropopause. Candidate chromophore molecules must satisfy the condition that they are produced sufficiently rapidly that convective pyrolysis maintains the observed chromophore optical depth. The condition is satisfied if complex organic chromophores are produced with high quantum yield by NH3 photolysis at less than 2,300 A. Jovian photoautotrophs in the upper troposphere satisfy this condition well, even with fast circulation,
assuming only biochemical properties of comparable terrestrial organisms. An organism in the form of a thin, gas filled balloon can grow fast enough to replicate if (1) it can survive at the low mesospheric temperatures, or if (2) photosynthesis occurs in the troposphere.
If anyone has access to the full paper I would love a copy.
How we know is more important than what we know.
For some reason, that makes me think of some prominent politicians...
Or some baddies in a SciFi series, "The Attack of the red Gas Giants!!"
try { do() || do_not(); } catch (JediException err) { yoda(err); }
if you have any plausible suggestions, by all means, make them. But till then, the only way I can see to get life is carbon-based life forms. Yeah, I could be wrong, but I'm betting on other life forms also being carbon-based. Not proof, but strikes me as a good bet.
But the detection of those elusive, small Earth-like worlds may be closer than you think
I've seen lots of Science Fiction movies about aliens that go from planet to planet, soaking up the natural resources of each, conquering and destroying them (making them uninhabitable), and moving on. Anyone else ever think we're the aliens?
I mean, we've already screwed up this one, and now rather than fix it (because wanting to do that makes you a "tree hugger") we're going after another. I can't say I'm against it, but it's just...creepy.
Perhaps the teraforming of venus or mars would be a more practical consideration for the next 100 years.
It'd take considerably longer than 100 years to terraform either planet. And that's ignoring the little issue that we haven't even visited either one with anything but robotic probes still.
The lack of fast space travel hampers terraforming efforts as well, since any reasonable plan involves mining the rest of the solar system for necessary components - nitrogen and ice water for Mars, who-knows-what for Venus (and Venus is further from the resources in general, although that's entirely dependant on orbital mechanics really).
In any case, most "realistic" terraforming timelines are centuries long. And even if we had the technology to do it (we don't), there's a minor issue of finding funding for that long of a period and being able to actually come out ahead of the game after compound interest has taken it's toll (contemplate 1 trillion US dollars at even 1% interest for 500 years - it requires a 14740.30% rate of return).
Yes, we have absolutely no way to populate another world right now either. But the incentives to go there would be considerably higher than trying to terraform a neighboring planet. If nothing else, a fly-by probe moving at a considerably fraction of c could visit a solar system ~20 light years away in under a century. If it has the right equipment it should be able to tell us if there's life on that planet. That would go a long way toward answering the "are we alone?" question.
Of course, there's the issue with financial backing there too, and the minor nit that we have absolutely no infrastructure (particularly solar power stations) to do this either, but if you want to put an somewhat arbitrary 100 year limit on goals, then a probe flyby of a nearby earth-like planet seems more realistic to me than terraforming.
Power-law distributions (more smaller stuff) suggest there should be lots of earth-size planets. However the current methods can only see fast-moving larger-than-Jupiter planets. The most popular method is measure faint doppler shifts over months to years. Terrestrial pectroscopic resolution limits this to about 10x Jupiters. Space-based methods may be more sensitive.
.0001% of time the planet is eclipsing,
and (c) you aren't seeing a variable star like
Algol. The US will soon launch a special telescope called Kuiper to watch one splotch of sky for five
years continuously to catch planetary eclipses.
Kuiper is notable for its 350 megapixel camera.
Another method is to look for eclipses of planets across the stars. This presumes (a) you are seeing another solar system edge-on, (b) you are lucky to catch the
A third method is infra-red, which can see earth-size in newly forming planetary system dust-clouds. These would be too young and unstable to have evolved intelligent life on their own, but could be colony sites.
I think any very serious attempt to look for Earth-like planets (e.g., rocky crust on the planet instead of a gas giant like most of our Outer Planets) will have to wait until future generations of space telescopes become available after 2010.
The problem is that even with advancing telescope technology on ground-based telescopes they still can't completely overcome the refractive effects of the atmosphere, which reduces the quality of any picture taken even at high-altitude locations like Mauna Kea in Hawaii. With NASA working on the Next-Generation Space Telescope (NGST) and the European Space Agency working on something similar, we may just see after 2010 space-based telescopes with much higher resolving power than the Hubble Space Telescope; these might just be able to see fairly clearly the gas giant planet(s) orbiting nearby stars and could help deduce if there are rocky crust planets also orbiting those stars.
What does he mean by Earth-like? A small planet with an atmosphere? With oxygen and carbon dioxide in its atmophere? With a temperature range that might permit life? With oceans and landmasses?
By some definition of Earth-like, it wasn't long ago in geological time that Earth wasn't very Earth-like. And on the same time scale, it won't be Earth-like for long.
The higher purpose of scientific exploration is to find something weird, not something familiar. The more unEarth-like, the better. A discovery that confirms a theory is useful but a discovery that challenges a theory is the name of the game.
I'm glad you posted the section you did here, as I didn't remember his exact words (and I can sometimes be a stickler for comparing what he said to what people think he said.) It says, "We are close to being able to find Earth-like planets." He doesn't say we're close to finding one, just that we're close to being able to find one. That's quite a big difference, especially when you consider that space is mostly empty. It could be 20 years after we are able to find one that we actually do.
Just to kind of explain that to some of our slower readers... and this is in no way accurate, but just an example to help understand... if putting a coke bottle on the end of a telescope enables us to detect Earth-like planets, then we still have to search the skies with that telescope. That could take a long time, with the vastness of space.
It's easy to stand out when the general level of competence is so low.
The closest thing that has been discovered is the two gas giants around 47 Ursa Majoris. This is the planetary system that so far looks most like our own. The two giants have less extreme (more circular) orbits than most of the ca 70 planets found, which also contributes to make it look a lot like ours. Gas giants can be an important contributor for life to appear on a smaller planet, since they act like magnets for asteroids and other debris, sheltering the smaller planets and giving life a chance to evolve.
Opinions stated are mine and do not reflect those of the Illuminati
Actually, he's referring to this older Slashdot article, which you must've not read.
Now whether this formed in a vacuum or not is a technicality. The scientists shone high level of UV light on a chunk of ice containing ammonia and methyl alchohol at a temperature of 4K and found traces of 3 amino acids had formed. The amino acids themselves formed from the surrounding ice slurry which was in a vacuum, ergo "amino acids are formed in a vacuum."
If it's for-profit but free, you're not the customer -- you're the product (e.g., the Slashdot Beta's "audience").
Actually, the article quotes him as saying "We are close to being able to find Earth-like planets", not that we are close to finding one. The actual quote is a lot easier to make an educated guess about. We can figure out that we need X telescope resolution, Y processing technology, Z other technology and/or techniquest, and we have X-n telescope resolution, etc, and we can more-or-less reasonably project how long it will take us to get to n amount of technology. Thus we can make a reasonably educated guess as to how long it will take us to have the technology to actually find such planets.
Parallax determines the presence of an undetectable massive companion by the sinusoidal proper motion of the star system over a course of a few years. On the ground, you can do this for only a dozen of the closest stars (10 parsecs) or so.
Doppler reflex motion detects the companion by the Doppler shift in spectral lines in the parent star's spectrum as the planet/star orbit about their mutual centre of gravity. You can do this out to 100 parsecs or so.
HD209458 was a candidate from the Butler and Marcy Doppler survey that had a high inclination (edge-on) orbit. Brown and Charbonneau then did photometry to get the transit of the planet across the star's disk. Parallax did not come into it.
Dr Fish
Maybe they just pick who they want to talk to.
Chris Beckenbach
In it Mayor says (my translation) "In 1995 the chances of finding an exoplanet were very small." And still he did. There is no guarantee to find an earth-sized exoplanet ever, but it is quite possible to find one within a year of being able to - or less.
And no, it is absolutely not "shooting in the dark" to say that we'll soon have the ability to detect earth size planets. If these devices work, we can find them if they are there. Just like we were able to find exoplanets in the mid-90's after developing the tools to do so, and just like we actually did.
Lars T.
To the guy who modded me down from perfect to terrible Karma - Apple haters still suck
Yes, the probability of any one system having an edge-on set of orbits for its planets is small. That's why a few groups are monitoring globular clusters with up to 10e6 stars in them, and are also looking toward the bulge of the Galaxy, where you get many stars in a given field of view.
A small probability multiplied by lots of stars all at once = a reasonable chance.
A second selection effect also helps you. All the orbits of the planets in our solar system all lie in a common plane called the ecliptic. It's a result of the conservation of angular momentum.
So the trick is, find a star with transiting hot jupiters, then intensively monitor that system to find the smaller signals of smaller diameter earth-sized planets, as chances are that they will also transit the star's disk!
Dr Fish
We've been broadcasting interceptible radio and tv signals out into space for at least 70 years now, and we can't go out and stop those radio waves from continuing on. Any sufficiently advanced aliens living within ~70 light years of earth already knows about us, guaranteed.
Shop Smart, Shop S-mart!
shh, this planet here is one of the most habitable in the universe, but also one of the most dangerous, with sharp venomous teeth. now we're just going to sneak up on it.... oh no, it's got life forms! crikey!
Katz bothers not with such mundane details as the location of these planets. He's more interested in the implications of the existence of such planets. He has no idea what implications those might be, but he'll definitely be sure that they will change the way we live our lives.
Get ready for articles with words such as "Earth-centric", "Extra-terrestrial Imperialism" and "Trans-globalism"
"Don't blame me, I voted for Kodos!"
If the instrument is only a refinement of existing ones, it's a matter of simple calculations what size/weight planets should be detectable with it. A little Googleing brought me here, with planet-figure.pdf being a diagram of Planet Detection Methods, and planet-paper.pdf being a (longer) paper.
Lars T.
To the guy who modded me down from perfect to terrible Karma - Apple haters still suck