Who Needs NASA? Exoplanet Detected Using a DSLR 108
Iddo Genuth writes Until 20 years ago even the best telescopes in the world could not detect a planet outside our solar system. Now, with the aid of a basic DSLR, low cost lens and some DIY magic, you just might be able to "see" ET's home planet for yourself. Your DSLR can do much more than just take a few nice portraits or the occasional vacation photos – if you have some DIY experience (O.K. a bit more than just "some"), you might be able to repeat what David Schneider was recently been able to do — that is, building his own planet finder using only inexpensive photo gear, low cost electronics, the right kind of software and a lot of patience. Although Schneider was "only" able to rediscover an already known exsoplanet (some 63 light-years away from us), what he did — and more importantly how he did it — might allow planet hunting to become closer to SETI@home than NASA's 550,000 million dollar Kepler space telescope project.
Billions and billions: (Score:5, Informative)
"550,000 million dollar Kepler space telescope"
I think you're about 3 orders of magnitude too high.
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Depends. US and China uses period as decimal sign, South America, Europe and Russia uses comma.
Perhaps it's just your interpretation of the numbers that is incorrect.
Re:Billions and billions: (Score:5, Funny)
Yes, for example when filling out census in Russia, it is very important to put that you have 2,000 children (Lena and Igor). If you put just 2, people would consider that you are just rounding it off.
This even appears in the food market - you need to specify that you want to buy 1,000 egg, otherwise, given current economic troubles, they could cheat you and try to sell you only 0,945 of one, which you would notice only at home when your cake fails.
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0,945? Would that be a Russian bakers dozen?
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This site is based in the US. Therefore, the convention it follows should be that of the US. Any use of a comma as a decimal delimiter here is simply wrong.
Besides that, the use of six digits when only two or maybe three are actually significant is just clumsy.
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Google has $550 million, the article has $550,000 million. Out by 10^3.
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no, there is 3 zeros too many.
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Dereferencing the blog spam: (Score:3, Informative)
The actual article is here, on ieee.og
http://spectrum.ieee.org/geek-life/hands-on/diy-exoplanet-detector?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+IeeeSpectrumFullText+%28IEEE+Spectrum+Full+Text%29
And making my link a link: (Score:5, Informative)
The more complete source article [ieee.org]
Re:And making my link a link: (Score:5, Informative)
The more complete source article [ieee.org]
As someone posted below, here [cloudynights.com] is the forum post with some data, and here [marshall.edu] is the raw data with more plots. This is really awesome, but you have to temper your enthusiasm when you realize he knew exactly when to look and how much the brightness should drop, and he chose a relatively bright star (apparent magnitude +7.676, which is just barely too faint to see with the naked eye) with a relatively large exoplanet to image. There is some wiggle room there, but the data is pretty noisy, so it will be pretty tough to spot new exoplanets like this.
In comparison, Kepler-67b is a confirmed exoplanet 3610 light years away, orbiting a star with an apparent magnitude of +16. That is, take the light received from the star this guy imaged, divide it by 2000 (less than 0.05% the brightness), and Kepler can still detect exoplanets passing in front of it. The Hubble and Keck Telescopes have imaged stars with magnitudes of +30 or higher. So to answer the headline (in case it wasn't already obvious), we still kinda need NASA.
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Also, from the Wikipedia page on HD189733b:
- HD 189733 b orbits its host star once every 2.2 days
- This planet exhibits one of the largest photometric transit depth (amount of the parent star's light blocked) of extrasolar planets so far observed, approximately 3%.
What he did was cool but this exoplanet is probably one of the easiest to detect.
There a plenty of nice things that can be done with a DSLR and a cheap lens and none of those will ever replace NASA or re
Who needs NASA? David Schneider does. (Score:5, Insightful)
This is a really cool project, with a terrible headline. Without NASA (or perhaps the ESA, or whatever space organization first found this exoplanet), David Schneider wouldn't have been able to look up the timing for the planet's transit. He wouldn't even have know to try taking pictures of that particular star. He'd have to take a lot more photos over a much longer time, over a much bigger area of the sky, and run a lot more image comparision software for a lot longer, before he's have found that transit.
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Obviously. This is a called a TEST of a system. Now he has shown the system works he can look at other stars. He doesn't need to know the transit time up front, all he needs to look for is a regular pattern in the observations (although I'd wager you need a few orbits to get a good signal; there's a lot of atmospheric noise to contend with; and a few orbits could take months or years).
But the point which you missed is that now a thousand guys with DSLRs can start searching for exoplanets, which scales th
You too can discover Jupiter's moons using only (Score:5, Funny)
a smartphone and an app!
Well ok so some Italian already discovered Jupiter's moons, but if they hadn't, you could!
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+1 for "some Italian"
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He didn't even want to risk being gender-specific about it.
Re:You too can discover Jupiter's moons using only (Score:5, Insightful)
Even with Slashdot's slightly hyperbolic headline, the summary correctly reports the planet as having been "detected" rather then "discovered", and clarifies that this was "only" an already-discovered exoplanet (as does the original article).
If that was your implied criticism, then, it's not valid.
If you understood this, but your point was that "detecting" an already-known exo-planet was pointless because it's alredy been done... even though the person involved did it with equipment orders of magnitude cheaper and lower-end than that originally used by NASA less than a decade back, and which few of us would have assumed possible, which *is* the point here... then Slashdot probably isn't the place for you.
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Yes, part of it is depressing. All those planets out there so far away from us. Even worse, if intelligent life is out there, it is likely too far away for us to communicate with. We might not be alone in the Universe, but there might be tiny islands of intelligent life scattered around the Universe - each island unable to talk to the next island over.
On the other hand, just think about how much we've progressed as a species. It wasn't too long ago that we'd see a comet in the sky and think "that's a ba
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Not to mention that whole "time dilation" thing. Even getting anywhere near a significant percentage of the speed of light, sure, the riders/astronauts in the ship will get there in whatever "shorter" time it ends up being...but those of us who sent them off will grow old and die before they ever reach the destination. So very completely and utterly depressing.
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I feel that one, my friend. I'm always deeply fascinated by all we can see and find in the observable universe...then immediately depressed that we're unlikely to explore these worlds, solar systems, etc. [in my lifetime anyways].
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Have faith, that Science does not already know everything in the universe.
And, the increase in the amount of stuff that we -do- know, is increasing rapidly!
Check out the NASA report, on the microwave resonators that produce thrust... and have hope. 8-)
all credit is due.... (Score:2)
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What's the point of using the worlds best telescope to use it for taking pictures with the worlds worst digital camera? Wouldn't it be more sensible (and probably cheaper too) to use an average camera and a fitting telescope? That feels like using a P2 powered machine and then stuffing two bleeding edge graphics cards into it to get an average gaming experience.
this isn't all that new (Score:2)
We need NASA (Score:3)
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Project plan:
Years 1 - 28: Argue about funding, contractors, replacing managers, etc.
Year 29: Develop faster than light technology.
Year 30: Launch FTL rocket, travel 30 light years in 3 minutes to reach the star.
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Finally a way for geeks to get laid? (Score:3, Funny)
"Honey, I just discovered a planet and I'm going to name it after you. An entire planet."
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You are about to see a black-hole, forever...
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Wife's response: "It's a gas giant? A GAS GIANT?!!! You named a gas giant after me?!!!" *beats husband with his DSLR*
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To name exoplanet after your SO, take your girlfriend or wife's first name, put apostrophe and s after it, and the word "ass"
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"Does this planet name make my gas giant look giant?"
Luck? (Score:3)
If the article is correct it's only useful for checking transit events. The article talks about "a target star". "A star" has a low probability of having a planet in an orbit that gives transit events. Depending on the orbit of the planet it is next to 0 to 10%.
That is why the expensive systems check many stars at once. Kepler monitors 145,000 stars at once
That doesn't mean much. NASA always lacks money to do awesome stuff. So I feel that cost is a good metric here:
Kepler monitors 145,000 stars and costed $600,000,000. That means $4,138 per star
This costs $300 + $100 + some work = +/- $500 per star. If the same software could be used then it might be possible to check more stars with a single DSLR. Maybe even a hundred.
That means $6 per star (naively assuming his setup is sufficient for large scale deployment)
I say: if and when Kepler dies we should stick a couple of them on every observatory we have and have full time monitoring across the planet. False positives drop with more data.
False negatives would still require different detection methods since most exoplanets don't transit. However if we have this set up we might be able to add thousands of spectrometers to it to detect Doppler shift events. Then the only planets with low detection chance are the ones where we look directly on the top (or bottom) of their orbit.
Sensitivity is still an issue (Score:2)
A DSLR has managed to detect a large planet in a fast orbit around a small, close star. Kepler is sensitive enough to detect earth-sized planets orbiting G-type stars at 1AU, A DSLR (or even conventional telescope) can't replicate that.
I suspect most (all?) of the transiting planets that today's DSLRs could detect have probably already been detected by sky surveys anyway.
What's with the condescending title? (Score:2, Insightful)
I really want to think that this was a great feat of hardware hacking, but the title of the summary is terrible. The capabilities of space telescopes are designed to overcome the obstacles which plague our earth-bound ones.
Saying that this is a viable replacement for the data coming from a source with lesser disturbances is just undermining the work of a lot of people.
I must admit in skeptical (Score:5, Insightful)
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I'm not at all. I've seen some crazy people do some stuff with strange equipment in the local astronomy club. I quizzed an older gentleman at the last Astro-fest who appeared to be taking photos of what I thought was nothing, no nebula, no galaxy, turns out he was recording the magnitude changes of variable stars for an open amateur database that effectively crowd sources science efforts.
He did this photometry with a Canon 1000D. A lot of effort was put into characterising his sensor and detecting the optim
Real advantage (Score:3)
One cannot escape the fact that bigger apperture telescopes can record fainter
stars, and/or perfom the photometry of bright stars with more precision than a simple camera.
To detect exoplanets one needs both large samples of stars recorded as continuously as
possible over several years and high precision photometry. Besides being cheap, the advantage
of a small camera is than the field is larger. But with a larger telescope in space like Kepler one
can target regions of the sky with density of stars optimal for the CCD/camera combination, and
observe continuously for months with the same instruments, which is crucial for differential
photometry. Thousands of amateurs worldwide detecting as many new exoplantes as Kepler
would face the problem of coordinating the analysis of huge amounts of heterogeneous and
incomplete data (due to day/night and weather interruptions in differently dark and transparent skies).
The real question is wether crowdsourcing planet detection is cheaper for global economy at equal scientific return than with state sponsored research. Perhaps the most important benefit of such an
activity is educational and promotional for research in general.
Amateurs have already contributed (Score:1)
Many amateurs have already contributed to the effort. Variable Star Observers(VSO) have been collecting information for a very long time. This information has been useful for much more than just the search for exoplanets. Taking part in VSO efforts is one of the few ways that private individuals in their spare time can make real contributions to data used by current day scientists.
Exso? Really? (Score:2)
Come on, really? In a story about exoplanets you can't even spell exoplanet??
Could I do that? (Score:2)
That question was asked by Bruce L. Gary and the answer is what he wrote in his free book: EXOPLANET OBSERVING [brucegary.net]
FOR AMATEURS
Re:Ditch the DSLR (Score:5, Informative)
Want a shallow depth of field? Think you need a large lens / fast lens? Why? When the computer can take multiple photos at different focal lengths and calculate the depth properly. Why twiddle with zoom and f-stop?
Because by the time my camera gets around to taking several photos at various focal lengths, the fast moving subject I was trying to take a picture of already left the scene. But I have the opposite problem (since I can fake a shallow depth of field in photoshop) -- I have to open the lens all the way on my P&S in any kind of low-light situation since the sensor is too noisy at high ISO's, so I end up with a shallower depth of field than I wanted.
Want a fast lens? Point and shoots go down to f1.8 now. I can photograph the craters on the moon with a pocket sized G7X without a tripod FFS. How often do you try to detect planets in other solar systems?
I want a fast lens *and* a larger, lower noise sensor than I can find in most P&S cameras. But I don't use that fast lens for taking pictures of planets or the moon.
Want to shoot wildlife at a distance? Think your DSLR is the best option? Think again, you should be using a higher pixel camera at a lower zoom, because you'll have difficulty tracking the moving object at high zoom with that lumping great lens.
Right, all those sports photographers that use the big $8000+ 300mm telephoto lenses could save some money and just get a point a shoot with more pixels than his 20MP DSLR and he can just crop down the pictures to give him a nice 3MP shot of the winning touchdown. Pixels are pixels, right? The 1/2" sensor on a 20MP point-and-shoot is just as good as the 35mm sensor on his DSLR, right? And what possible difference could there be between an $8000 lens and the lens on a $500 P&S?
Want to shoot movies? Do you see any pros using DSLRs? They use a Red or similar, not a Canon EOS.
Here's a list of 30 movies and TV shows that have been shot in whole or part on Canon or Nikon DSLRs:
http://www.imdb.com/list/ls059... [imdb.com]
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Smaller sensors also equate to higher noise levels, thus are they limited to working in lower ISO levels than the larger sensors. Fast lenses ( f2.8 and below ) only go so far. You'll need low noise high ISO capability for any less than optimal light stuff you plan on doing. ( Read that, just about anything outside of a studio )
W
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The moon does not qualify as low light beause it is directly illuminated by the sun.
Simply speaking it is as bright as any outdoor scene under broad day-light.
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The gp displays the standard ignorance of a novice photographer, who doesn't even know that he knows nothing about photography because his hardware allows him to take pictures he deems "good". There's a reason there are professional photographers out there that get paid well and use "pro" equipment, but until gp tries to take pictures outside the limited scope of a P&S, he won't realize how limited he is. Should he use a pro-sumer or better grade camera, he may be disappointed in his pictures not being "better" than the P&S, that's not a fault of the equipment but more his failure to understand how to use that equipment to get great pictures. And even then, great pictures don't just happen automatically, it is luck or many tries, and sometimes significant post-processing before a great picture is realized. To be fair, sometimes that is also achievable with a P&S.
Truth to this but lighting is the magic ingredient. PS skills especially well done work frequency sep and subtle accurate changes only go so far if it is poorly lit. I don't just mean artificially lit stuff but same goes for available light although admittedly I tend to use monoblocks in portraiture. Not a quality thing more for the control I have over all light sources and "on tap" perfect light any time of day.
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Truth to this but lighting is the magic ingredient.
Yes, lighting is key, but even with good or excellent lighting you are not guaranteed a great shot.
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Seriously, a DSLR sensor is 35mm because the film it replaced is 35mm.
Mostly wrong. Only high-end professional-oriented DSLRs have 35mm-sized sensors, the majority use smaller APS-C [wikipedia.org] sized sensors or something in that ballpark.
Re:Ditch the DSLR (Score:4, Insightful)
One reply has already gutted most of your points, so I'll work on the ones he didn't address:
Seriously, a DSLR sensor is 35mm because the film it replaced is 35mm. It's not an engineering choice, it was done so that owners of expensive lenses could use them on the new digital cameras.
Except that not all DSLRs are 35mm, in fact most of them weren't, and most of them still aren't. They were APS-C sized. Or in the case of 4/3rds they were even smaller and not even the same aspect ratio. Yet all the lenses magically still worked.
35mm has enough engineering decisions behind it,
Its not sized large enough to take in a normal range of light, and yet small enough to keep the lens size down so big zoom lenses are possible. It's sized for historic reasons, making it too big and thus limited.
And yet there's no definition for normal range of light and it seems every year there are changes to sensitivity. Are you saying that it was initially not large enough? What about now when cameras go to ISO25600 and beyond?
Lots of things are better done by digital calculation than lenses.
False. Leaving aside the technicalities of deconvolving and correcting for aberrations at different zooms and focus point, there's a much more fundamental saying: "Shit in. Shit out." Every correction make negatively affects an image that could have been right to begin with given how well lenses are understood.
How often do you try to detect planets in other solar systems?
Are you asking how often a man does his hobby? Who are you to question?
Want multiple lenses for those oddball occasions, go with Micro 4/3 like a lot of pros are doing now.
Why, and Who? Seriously I love my EM1 as much as the next person, but you'd be hard pressed to actually point out a pro using micro-4/3rds for anything other than an Olympus promotional video. As for oddball lenses, I think you'll find both the EF mount and the F mount will have a far wider and more oddball selection than anything 4/3ds.
As sensors have gotten better, and lower noise, the sensor in the DSLR has not shrunk in size because of the lens.
No. Quite the opposite. The sensor size has increased. The coupled larger format with the newer sensor technology now makes it possible to take photos that were previously impossible without fancy lighting and careful setups. Upping the sensitivity is no excuse for making things smaller when the benefits can be had across the board, especially since small sensors struggle to get depth of field down.
Big zoom lens are unworkable in DSLR because of the size of the sensors, they would simply be too long.
And yet they have been built and are in active use.
Likewise the size of the sensor is a big problem itself, its slow electrically.
And yet they are used in fast paced sporting situations and 60fps HD video.
So you end up with a camera with worse performance in normal situations, and designed for non-real world situations.
So a camera designed not to take pictures? I'm not sure I follow here.
Trying to find planets literally is what these camera are useful for!
No trying to find planets are what carefully calibrated and cooled CCDs are useful for. Before someone can use a DSLR for anything as technical as this they need to move heaven and earth to properly quantify how their system reacts as sensors used for photography are inherently non-linear trading off accuracy for other aspects. I know someone who uses his Canon DSLR for gauging the variability of stars. He literally recorded months of data before he had something useful enough that he could calibrate his camera for use on a single target.
The fact this works at all is amazing and a testament to the people involved, and definitely nothing to do with technology.