Slashdot Mirror
Two Telescopes Linked To Find Planets
glinden writes: "Two telescopes at the Kech Observatory have been optically linked to form the Keck Interferometer. The resolving power of this combined telescope will apparently be sufficient to see earth-sized planets around nearby stars." quoll contributes a link to NASA's own version of the story, too.
Gemini will not be an interferometer. For interferometry, you have to know the distance between the telescopes to an accuracy smaller than the wavelength used. Another thing is that you should either combine the beams from both telescopes, or get the phase information of each photon. In radio, it is possible to get the phase information. In optical, Keck and VLT can combine the beams. For Gemini, this would need quite a lot of optical fiber ;)
The main goal of Gemini is to have identical state-of-the-art systems for observing both northern and southern sky.
IMHO X-ray astronomy is much more interesting, but I fear it will take some time before we get the X-ray interferometer, but I have heard some rumours on it.
I'm not quite sure how to take that, QPT. I agree that the possibility for extraterrestrial life is a little slim, but there could be billions and billions of planets out there. Each planet makes such a discovery just a little tiny bit more likely. Besides, I'd rather have telescopes taking pretty, scientifically interesting pictures of space than pour more money into military research.
The real distressing partof your comment is re-introducing creationism into schools. You know, as much as I applaud the encouragement of religious fanaticism. . .
!-- wit --!
You're right. There is no realistic prospect of interferometry with Gemini using any current technique. The point of building the two telescopes identical was to cut down on design costs, to allow exhchange of instruments and so on.
It is interesting to speculate on how one might do real long baseline optical interferometry, by
analogy with the techniques used in radio astronomy. Essentially you would need to record the phase of the incoming light at (point in the image of) each telescope as well as its intensity. This phase calculation would need to be stable over the duration of the recording, requiring something like a laser whose phase didn't drift by more than a few femtoseconds per hour -- a clock accurate to 1 part in 10^18 or so. This will give a rather large (petabytes/second/pixel) dataset.
Once you have done that you need to track the relative movement of the two telescopes to within a fraction of a wavelength, which will require allowing for the Earth's rotation, tidal distortion, thermal expansion and contraction of the rock, special and general relativistic effects from the Earth's rotation and gravity and probably much more. A better approach might be to observe a known source near the target star and try and calibrate from that. Using three or more telescopes also helps.
Then it just comes down to a comparatively well-understood, if enormous, computing task, to combine the datasets from all the telescopes and synthesise an image.
COAST has five in it's array. It's first images were made in 1995.
----------------------------
-----------------------
Moderator's essentials
Thats not a moon. Its a space station.
Disclaimer: I know they can't detect Death Star sized objects with this. That is, not until its too late!
Some university in Britain did this a few years ago with an array of telescopes in a hexagon shape I seem to remember. They proved that this technology could take better piccies than Hubble. Beyond that . . . memory fading . . . can't . . . remember . . . any more.
I operate the VLT here in Chile. The VLA is in New Mexico (and is the telescope array seen in Contact). BTW: I know we also are close to "First Fringe" on the VLTI as well.
_ _ _
I was working on a flat tax proposal and I accidentally proved there's no god.
Also they have to keep the temperature of the whole system itself stable, or the beams will flex, and again distort the image.
I really hate Dan Patrick.
Actually, the velocity probably wouldn't be a problem. Just use an Orion. Then you could also put sufficient armor on it and carry plenty of supplies. Orion type ships don't have much problem with mass-ratio.
Best Slashdot Co
-- Have you ever imagined a world with no hypothetical situations?
Hmmm, I was just reading some SETI stuff in the current Sky & Telescope (Bah, they don't have the currrent issue online... this is the closest thing I can find...) ... where they discuss using telescopes to broadcast optical stuff to alien SETI hunters.
--
If the good lord had meant me to live in Los Angeles
Either that or you won't have to pay for laser surgery to get your eyes fixed!
Buzz Off
"What's that lump there? It looks like a red pill." .. "no, I think it's a blue pill..."
Just a tibit of correction. The VLT is not in New Mexico. You're thinking of the VLA - the very large array, run by the National Radio Astronomy Observatory. The VLT is in Chile and run by the European Space Organization.
The VLT is an optical telescope, and they are designed to do optical interferometry with 4 telescopes, but I'm not sure that this has been done yet. The VLA is an radio telescope, and interferotetry has been done with radio waves for decades. Essentially, the difficulty goes with the length of the wavelenght. I.e. the longer the wavelength, the more room for error you have when you stack the signals. That's why its possible to stack nearly 30 signals at the VLA, but we're only doing 2 or 4 in the optical.
This is really quite an achievement. And no, you don't 'listen' to the radio telescopes like Ms. Foster did in Cotact...
Also, Gemini is a joint project among *many* countries, spearheaded by the group here in the US. I'm not even sure ESO is a part of it. The members are Chile, US, Australia, Brazil, Canada, UK, and Argentina. Please check your facts before you do this sort of ting.
By the way, the OWL is a concept telescope which has yet to be developed and probably won't be for a decade or two. You are right, however, in your general ideas, but bear in mind that even what they are doing at Keck is very difficult, and it will be years before Gemini starts operating as an interferometer (and even so, I'm not sure if it's equipped to do it yet). Right now, Gemini is just starting individual science observations.
It really is an exciting time to be doing astronomy, professional or otherwise.
Sooner or later, I think, we will have a reason to try traveling through space
"Not because [it] is easy, but because [it is] hard." Cynical old bugger that I am, I still get choked up even thinking about Kennedy making that speech. Even though I know on an intellectual level that it's a carefully crafted piece of political manouvering, it touches some deep place that makes me believe that even our lazy, greedy short sighted little race can occasionally reach it's grubby monkey paw to grasp at all that is great and noble and transcendent.
If you were blocking sigs, you wouldn't have to read this.
I've thought of this before, but I didn't think they would do it on Earth. I was thinking that they should launch another Hubble and do it. In space you could easily move the telescopes closer together or further apart.
Of course, this increases the resolving power but it does nothing for light-gathering capability.
The problem is lenses. They simply have to be too big. What could we put in space that would act like a really big lens? The only way I know of to focus light without passing it directly through a lens or bouncing it off a mirror is with gravity.
It simply isn't practical for us to built a gravity telescope.
Is there anything else that will bend light? If we could create a large "light bending field" in space, we could get a lens the size of a planet. We would just have to be careful that we didn't put the Earth in the focus. Then again, maybe the Ant People from Andromeda are already planning to do that to us.
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
I'm suprised that this sort of thing isn't better done in orbit, where at least gravity and temparature are on your side. You could imagine slipping a few big mirrors up to the lagrange points, and focussing them on hubble or something for the inferomtery.
Just a thought.
So what are we looking to actually see with the Keck combo? Planets as small as Jupiter? Neptune?
Remember "Bring 'em on"? *sigh
A Beowulf cluster of these..
Sorry, I had to say it.
==>Lazn
Does that mean we can have a beowulf cluster of em?
Couldn't resist!
Are YOU listed?
Good point. Maybe I should sell convince the american government that the unstable, eroding cliff on the back end of my property is the perfect place for an observatory.
!-- wit --!
My nutshell is very course.
But the next leap forward is going to be European... ESO (European Southern Observatory) are constructing two identical telescopes in Chile and Hawaii (project Gemini.) How's that for a long baseline? ;p
And for bluesky "gee whizz" quotient, check out the Overwhelmingly Large Telescope (OWL)...
I've seen a chart somewhere (can't find a link - anyone?) charting aperture (light collecting capacity) of telescopes since Galileo. The Keck and other 10m class telescopes have moved the curve from a nice straight line to an exponetial curve - and that's not allowing for vastly increased computer power, active optics, and out-of-visible band stuff. Truly this is a fantastic time to be interested in astronomy, even (especially?) as an amateur. For a couple of thousand dollars you can do stuff in your yard that was the province of professionals only a few decades ago.
--
If the good lord had meant me to live in Los Angeles
Actually, this was planned *way* back.
The two Keck telescopes were not built simultaneously.
Keck I had seen first light and had already been in operation for quite a few years (IIRC)
before they started construction of Keck II beside it for the specific purpose of inteferometry.
I'm not a genious in optics, but I don,t understand how 2 parallel telescopes see smaller objects than 1 telescope.
Even if we do locate an Earth-size planet, I'm not sure if its even theoretically possible to figure out whether there is an Earth-like atmosphere. The othe probem is getting there. Even if we discover an Earth-like planet orbiting Proxima Centurai (4.3 light years away and our closest neighbor), it's impossible for us to get there. Prior to having the power to get there (even in a bit less than 4.3 years) we need new propulision technology, like nuclear fission (or preferably fusion) or even better, antimatter. The amount of energy needed to get to near-light speeds is huge, and with out current technology, unobtainable for a spaceship. And don't forget that even if we were able to make something like this, the people going there would be out of contact for almost 10 years. By the time we received a signal that they sent back from Proxima Centurai saying "We've arrived", they would probably be almost back.
Its reuquirements like this that make such things happen! When Kennedy announced that man was going to the moon by the end of the decade they didn't know if it really even possible. Almost ten years later after a lot of hard work and research by a great many people they worked out how, and they did it. Give people a challenge and a timelimit, and even better someone to compete against and they WILL find a way.
No, O2 has no prominent absorbtion band in the IR wavelengths that is going to be used. However, O3 (Ozon) is an extremely reactive chemical, and its presence implies that there is O2 (that can be dissociated by UV radiation and recombine to O3).
So, if you find O3 there has got to be O2 too.
/Dervak
Light from an extrasolar planet has been detected, in a sense, by a group of astronomers. What they did was to use the fact that the reflected light from the planet is blue-shifted when the planet is moving towards us in its orbit and red-shifted when it's moving away. It also varies in brightness in a characteristic way depending on how much of the planet we can see.
Essentially the researchers used very sophisticated image processing software to detect this "signature" pattern of colour and brightness variations in the light of the star (before processing the signal was 20000 times fainter than the noise). They can't point to any one photon and say "this is reflected light from the planet" but they can say statistically that reflected light is almost certainly present in their data.
Looking for new planets is a singularly boring endeavour. Who wants to put on headphones and listen for voices in the static coming in?
If there were aliens, we would have been visited already. After all, if time travel were possible, why has nobody ever visited us from the infinite future? Even if nobody in the next thousand years visits us, somebody in the next million years ought to, and any sane person would surely agree.
Obviously, we are alone in the universe.
But try and tell that to the liberals. Your biblical truths are right on the money. God wasn't just stroking himself when He created this planet, and we should recognize this when we spend those billions of dollars on telescopes. Perhaps then we might find some wisdom and put the money into Christian Bible academies.
--
--
"May the forces of evil become confused on the way to your house"
-George Carlin
The Keck Interferometer will be able to detect planets farther from their parent stars, helping to pave the way for future interferometers in space that will look for Earth-like planets, NASA said.
Correct me if Im wrong (im sure you will all have no problem with this request) - but we are not going to be capable of imaging the actual planet body but instead be capable of detecting the influence of smaller planets on their stars...?
Imaging an actual planet is very different from detecting wobbles in Star orbits... where the former is surely the 'holy grail' our planet needs to motivate - and provide perspective to our opportunity in the universe - and work towards a real and noble goal of establishing a permanent, self-sustaining, Human presence other than Terra.
Not only is Mauna Kea not likely to ever erupt again (see the "hotspot" explanation posted elsewhere), but my understtanding is that the site offers some of the most uniformly best seeing available within the US borders, due to its elevation, the smooth air flow off of the ocean (minimizing "twinkle"), and the distinct absence of light pollution. Not only that, but its proximity to the equator offers views well into the southern celestial hemisphere, allowing observatories based there access at one time or another to nearly the entire sky.
Even if there was a real risk of the volcano erupting, I'd still be very tempted to stick a telescope or two up there....
-- WhiskeyJack
very cool. hopefully they can get optical confirmation of extrasolar planets in addition to many other things...
Does this remind anyone else of SMP? :)
Yes, Columbus sailed for the economic benefit of Spain - and he had a hard enough time getting funding for that. If he had just said he wanted money to "go exploring," he would have had even more difficulty. Unlike Columbus, we don't have a large potential to expand trade routes or anything - it'll be mostly exploring for a while. My point is that I think we shouldn't let the lack of immediate economic benefit stop us.
That MAY be true if the reason for finding and imaging planets were to find extreterrestrial life, but it's not. That would just be the cherry on the cake. It is to get a better understanding of how our own planet came into existence, to learn more about how the universe is comprised, etc...you know, REAL science. Are you saying that finding other solar systems beyond our own isn't important? Sedondly, to say that a magical mythical god created life, when science has proven that we evolved, would be a tragedy. To stop all learning because God and the bible provide all answers would be a blow to discovery, BIG TIME. The Bible is a Christian book, what about all the other religions? Religion is required by the fact that every human being longs for the answers to questions of, "Where did we come from?", "Where are we going?", and "Why am I here?". Religion (whichever one you have been TOLD to choose by your social surroundings) answers all these questions nicely, and for that purpose. What would happen if we suddenly were to realize, that we are NOT alone in this vast universe. A universe that is so vast, that most humans can't comprehend the size and distances involved. What would happen to your religious beliefs? To find out that we are not only NOT alone, but that we are relatively young in the universal intelligence pool. What then? We live an a non-descript planet in the middle of a non-descript solar system in the middle of billions of stars that make up our Milky Way galaxy, one of billions of galaxies...and you're going to tell me that we are it?!?! Shame on you for your egocentric ideals. To project the hint that you KNOW that we are alone. Are you the ALMIGHTY god?! I think not, and no, you DONT know if we are alone, you couldn't possibly know, so why do you say these things??? We are finding the building blocks of life in deep "empty" space! So to say, that in trillions of tries, where live giving particles are found in all areas of space, just happened to evolve on OUR planet for no apparent reason (sarcastic), would be silly. To say that in the 20 billions years (our guess as of today as to the age of our universe) that our universe has been evolving, that Earth was the only place that life arose would also be rather simple minded. By the numbers alone, as stated by the Drake equation, to say that we are alone goes against the odds. Lastly, just because Mr. Alien hasn't walked up to your door and introduced himself/herself (PC) to you, DOES NOT constitute proof that we are not being visited on a very regular basis, now is it. To say that we will never be able to travel faster than the speed of light is also extremely narrow minded. We (well, other scientists actually) are now sending light at 3 times 186,000 miles a second, not to mention, we have STOPPED light, and then sent it on its way. To say that manipulating gravity wouldn't bypass the speed of light conundrum is also wrong. To warp gravity is to also warp time and space. We can concievably travel vast distances in a relative instant, all within the realm of reality, TODAY. Anyway, my rant is over. I just was blown away by narrow mindedness of some of the responses here. To know that we know LITTLE of the universe we live in seems to be forgotten. To assume (yes, makes an ass out of u and me) that we are it, and that discovery is BORING, is, well, illogical. Thank you for your time...Bartles and James
maybe i'm a pessimist here, but what happens if that 'dormant' volcano decides to wake up? WOuldn't that be a helluva large amount of lost money and equipment? I'm not American, but I really question the wisdom of putting an expensive lab on top of a volcano.
"It's dormant! Really!"
How many times have we heard THAT one before?
!-- wit --!
On reading the title of this story, my first thought was that they just stuck the eyepiece of one into the lens of the other. Kinda like Bart did with the megaphones in that one episode. Was wondering why they didn't try this before when it hit me that it was probably a bit more complicated.
College hasn't healed a genetically predetermined boneheadedness, it seems. ^_^
---
That MAY be true if the reason for finding and imaging planets were to find extreterrestrial life, but it's not. That would just be the cherry on the cake.
It is to get a better understanding of how our own planet came into existence, to learn more about how the universe is comprised, etc...you know, REAL science. Are you saying that finding other solar systems beyond our own isn't important?
Sedondly, to say that a magical mythical god created life, when science has proven that we evolved, would be a tragedy. To stop all learning because God and the bible provide all answers would be a blow to discovery, BIG TIME. The Bible is a Christian book, what about all the other religions? Religion is required by the fact that every human being longs for the answers to questions of, "Where did we come from?", "Where are we going?", and "Why am I here?". Religion (whichever one you have been TOLD to choose by your social surroundings) answers all these questions nicely, and for that purpose.
What would happen if we suddenly were to realize, that we are NOT alone in this vast universe. A universe that is so vast, that most humans can't comprehend the size and distances involved. What would happen to your religious beliefs? To find out that we are not only NOT alone, but that we are relatively young in the universal intelligence pool. What then?
We live an a non-descript planet in the middle of a non-descript solar system in the middle of billions of stars that make up our Milky Way galaxy, one of billions of galaxies...and you're going to tell me that we are it?!?! Shame on you for your egocentric ideals. To project the hint that you KNOW that we are alone. Are you the ALMIGHTY god?! I think not, and no, you DONT know if we are alone, you couldn't possibly know, so why do you say these things??? We are finding the building blocks of life in deep "empty" space! So to say, that in trillions of tries, where live giving particles are found in all areas of space, just happened to evolve on OUR planet for no apparent reason (sarcastic), would be silly. To say that in the 20 billions years (our guess as of today as to the age of our universe) that our universe has been evolving, that Earth was the only place that life arose would also be rather simple minded. By the numbers alone, as stated by the Drake equation, to say that we are alone goes against the odds.
Lastly, just because Mr. Alien hasn't walked up to your door and introduced himself/herself (PC) to you, DOES NOT constitute proof that we are not being visited on a very regular basis, now is it. To say that we will never be able to travel faster than the speed of light is also extremely narrow minded. We (well, other scientists actually) are now sending light at 3 times 186,000 miles a second, not to mention, we have STOPPED light, and then sent it on its way. To say that manipulating gravity wouldn't bypass the speed of light conundrum is also wrong. To warp gravity is to also warp time and space. We can concievably travel vast distances in a relative instant, all within the realm of reality, TODAY.
Anyway, my rant is over. I just was blown away by narrow mindedness of some of the responses here. To know that we know LITTLE of the universe we live in seems to be forgotten. To assume (yes, makes an ass out of u and me) that we are it, and that discovery is BORING, is, well, illogical. Thank you for your time...Bartles and James
Are the scientists going to have to use those blue and red glasses to see the outcome of the pics? and how do you program that? Or is it like the stereovision thing? DanH
Cavalry Pilot's Reference Page
Cav Pilot's Reference Page
UNIX - Not just for Vestal Virgins anymore
Actually, we haven't even been able to SEE these giant planets. We know they are there by watching how stars wiggle back and forth as they get pulled by large planets orbiting them. The other method used to detect extra-solar planets has been to look for large planets crossing directly in front of their stars... this causes a periodic dimming in the light reaching our telescopes. But by no means have we ever been able to SEE these planets.
...only one baseline. The visibility of their interferometric signal is limited, they are only sensitive to certain spatial frequencies.
Damn, we need an array of these things. O wait, VLTI.
We are all in the gutter, but some of us are looking at the stars
IANAPA (I am not a professional astronomer)
No, this instrument will not see Earth sized extrasolar planets. Read the article.
This has been thought of before, and not even this past century, but only recently (past 20 years) has the tech been there to actually DO this. The optics and the placement of them, esp in the delay line, has to be quite precise. We're dealing with fractions of wavelengths here.
Basically it works like this: You have two telescopes, and the two light beams are brought together accurately so that they create interference fringes (hence the name interferometer). The interference fringes tell you about the light at a specific spot in the sky, in a very narrow angle (well, a REALLY REALLY narrow angle). From this, maps can be made of spots on very active stars, etc. (None of this is seen directly). Effectively, what you get is the same resolution of a theoretical mirror that's the same diameter of your baseline. You just don't get the light grabbing ablity of that theoretical mirror.
Dim light is the bane of interferometry. In an ideal world with ideal funding, interferometers would be nuked in favor of full sized optics kilometers across, but who's going to foot the bill?
The longer the baseline, the narrower the angle you can see, hence more resolution. Keck is a good start, but the baseline is way too narrow for what people are speculating on this weblog. Maybe someday when someone finds the funding, we'll have a space based interferometer with big mirrors and a few thousand klicks in between for a baseline.
This is more of a smaller! better! thing. Instead of planets bigger than our gas giants, hopefully we'll find more Earth sized ones.
Then we can look closely at radio tx's from that area of space. Maybe we'll find intelligent life. Maybe we'll just find more space for the 6 billion known intelligent lives.
Cheers,
Rick Kirkland
What next? Are they going to add a blue filter on one and a red filter on the other???
hmm... for fun I enjoy launching DDoS attacks against 127.87.42.5
I'm no professional, but...
Nothing we have can see extrasolar planets. The planets that have been detected thus far (AFAIK) have all been roughly the size of Jupiter or larger, and were detected indirectly by looking at the motion of the parent star. The gravitational pull between the star and its satellites causes the star to "wobble" from our perspective. That is, of course, only if the system's axis is mostly perpendicular to our viewpoint. If it's parallel, a doppler shift measurement can be used.
So while the Keck Interferometer may not provide an actual look at a planet, the increased clarity *should* allow us to detect the smaller wobbling caused by smaller orbiting masses (they estimate Earth-sized). At least, that's my interpretation of all of this.
But ofcourse. Science is the only way to find the answers to our questions.
Will work for bandwidth
I agree. It might not be possible with current technology, or technology achievable within 20 years. But do you think that we are trying as hard as we could?
Maybe the state's highest function is to grind out insoluble problems. (Zelazny, Hall of Mirrors)
Ok so this thing will help detect the presense of planets around suns. Here's a question:
How long do you think it will be before we can actually see big "high" quality pictures where you could make out features on the surface etc?
Is such a thing possible without actually visiting the system?
No, I did not read the f***ing article!
Abso-fucking-lutely!! :)
I couldn't agree with you more! Many of Terra's problems are because of lack of focus and 'in-fighting' - if the whole world suddenly woke up one day to a 'newscast' saying 'This is the image of another planet that has oxygen, water, and is capable of sustaining us' everything would change! Instantly! It would be like a visit from Aliens. If we could ever show people this - they would stop fighting about Coke-vs.-Pepsi and other 'in-bred-cockfighting' and start thinking for a moment; We can actually GOTO ANOTHER PLANET!
I just hope that someone is able to produce an image of some planet - not a wobble - but an image.
Now, the question is: How do we actually send anything (ourselves even) millions of light years away???!?!! This is the non-trivial part of the problem.
There are other factors 'working against the journey' so to speak.
It would take emmense propulsion power to get a craft of any reasonable mass up to near light speeds.
Technically, near-light speeds are attainable with enough propulsion force.
But, there's a lot of crap out there. Rocks and Dust, perhaps, but at those kinds of speeds any stray bits of matter in the way might as well be a brick wall, because they're coming right through the hull of any vessle that hits them.
Supposing you point your craft into the right trajectory, you then have to spend a long period of time accelerating up to the speed. You're THEN going to have to fly at that speed for several years hoping you don't plow right into something like a large rock, or a gravel cloud, or a really slow UFO.
And ONCE you've now pulled off two impossible stunts, you have to go for a third by stopping, which is going to take up just as much power as getting yourself UP to this speed (and let's not even get into the troubles associated with the attitude control of a vessel trying to come down from almost-photonic speeds.)
Then of course you have the superficial problems of keeping those silly humanoid things onboard alive for the journey. Food. Water. Environmental control. Internet Access. It's a real pain.
"Everything you know is wrong. (And stupid.)"
"Everything you know is wrong. (And stupid.)"
Moderation Totals: Wrong=2, Stupid=3, Total=5.
Don't look at the sun with those babies!!
Hawaii=Mountains with Volcanoes West Virginia=Mountains with no Volcanoes Do the math. Which one would you trust with a multi-million dollar telescope?
You stupid bastard, you don't have no arms left. It's just a flesh wound.
For this to work, we'd need to build a GIANT mirror about 40 million light years away. Oh, and if you want to look at dinosaurs, someone would have needed to build this mirror 40 million years ago. I guess we could blame those slack-off primates for not getting this project rolling back then.
A couple of people have asked questions about detecting planets, so here goes...
There are three or four popular methods for looking for planets, and the differences are quite subtle (well, they were to me).
The first method is Doppler velocity detection - the planet and star both orbit about their mutual center of gravity, a point somewhere near the center of the star as the mass of the star >> mass of the planet. The light of the planet itself is not detected, but a spectrograph analyses the stellar light to measure the velocity of the star with respect to the Earth. This is due to the Doppler effect, i.e. the starlight is slightly blue-shifted for the star coming towards us, red-shifted if it's going away.
After subtracting off the eath and sun's velocities, and taking measurements over a few years, a periodic shift is seen in the star's velocity and this is attributed to the gravitational influence of a planet. To date, this is the method that has pulled out all the detections so far.
However, the reflex motion of the star is only about 10 meters/second, and the spectrograph can only detect signals typically bigger than 3 meters/second. Also, only large planets near to the star are easily detectable.
A second method is planet transit - if the orbital plane of the planet is edge-on to the our Solar system, then the planet can move between us and the star and the starlight will dim for a few hours as the planet crosses the sun's disk - the trouble with this method is that you only see planetary systems that are edge on as viewed from Earth. To dats, only one system has been discovered with this method, and even that one was suggested by a Doppler velocity search.
The third method is a variation on interferometry called 'nulling' interferometry, and relies on the wave nature of light. AFAIK, the Keck interferometer is quite a way off achieving this sort of performance, but the trick here is that the light from the two telescopes are combined in such a way that the starlight cancels out but the starlight reflected from the planet's atmosphere is not cancelled out.
One way of thinking of this is looking at a car's headlamp and a bicycle lamp next to each other, and then looking at them through a picket fence. By moving your head laterally you can get one fencepost to block the car headlamp, and get the bicycle lamp light to shine through one of the gaps. The separation of the two telescopes then determines the effective pitch of the fenceposts.
Yes, but since it was lynx, they only observed the tag value in place of the real image.
If this super-telescope will allow us to look at earth-sized planets, will it also allow us to gain more insight into those fifty or so planets that we have already discovered? It did not sound that likely from the NASA article, more that it would simply allow us to detect these same planets more directly. Other than simply gathering information, what are we gaining from this? It does not sound like we will be learning much other than possibly locating a few more planets that we know absolutely nothing about. Someone clue me in on what the benefit is with this, beyond simply being 'BIGGER! BETTER!'
By this same argument... I'm going to conclude that Kentucky surely does not exist since I haven't yet ever met someone from there. Any sane person would agree.
Just wait until they work their way up to building this. Then we'll really start seeing the good stuff.
this space intentionally left blank (oops)
The resolving power of this combined telescope will apparently be sufficient to see earth-sized planets
Whereas the article says:
The Keck Interferometer will be able to detect planets farther from their parent stars, helping to pave the way for future interferometers in space that will look for Earth-like planets, NASA said
To find Earths (at least directly) you have to go to space Don't expect this for another 10 years or so.
Or is this like the time that the NYTimes reported a spun mercury reflector as high-tech?
Actually, I'd imagine the linkage itself is the high-tech part; the sort of deal where astronomers have wanted to do this for ages but actually hooking the thing up was beyond the ken.
Nyarly is going to stop thinking out loud now. Alternatively, consider this a request for more info...
IP is just rude.
Is there any torture so subl
Space exploration has, to some extent, died off. We spend a lot of time heaving new shiny things into orbit, but we don't seriously talk about new colonies or settling other planets.
I wonder, if this telescope spotted an earth-sized planet, suitable for life, with an earth-like atmosphere, would space research undergo a rennisance? Would the idea that "we can go there!", with a very specific there in mind, a there you could point at in the heavens, somehow inspire the human race?
Maybe the state's highest function is to grind out insoluble problems. (Zelazny, Hall of Mirrors)
It could happen... .. have you seen enemy of the state. With that kind of power, they could count the number of hairs on your head!
Other than the obvious financial constraints, is there a law preventing you from putting your own 'scope in the sky??
The possibilities are endless...... talk about the ultimate webcam.
The thought of big brother keeping an eye on my every movement 24/7 does scare the shit out of me though.
Live today. Tomorrow will cost a lot more!
Hey, they found stars in my web browser? :-)
Sorry... just found it funny...
"Giving money and power to government is like giving whiskey and car keys to teenage boys" P. J. O'Rourke
Assuming NASA survives all the politicians padding their districts with pork while at the same time cutting valid science programs ...
which doesn't seem likely ...
the Terrestrial Planet Finder tentatively scheduled for 2011 will be the mission that actually detects, images, and analyzes light reflected by Earth-sized worlds within 50 ly of Earth.
The difference between observations made by Keck, those made by SIM, and those made by TPF will be comparable to the difference between the telescope used by Galileo, the telescope used by the average small college observatory, and the Hubble.
Get off my virtual lawn, you damned virtual kids!
world's biggest pair of binoculars ?
test the chupacamera
-mind different
*clears throat* That would be an Interoceter, Earthling.
!-- wit --!